Tag Archives: insects and mites

Hymenoptera, Insects, Mites & Earthworms

Quadrastichus erythrinae Kim | Erythrina gall wasp

January 15, 2016 Jason Leathers

California Pest Rating for

Quadrastichus erythrinae Kim: Erythrina gall wasp

(Hymenoptera: Eulophidae)

Pest Rating: B

PEST RATING PROFILE

Initiating Event:

In April 2015 the United States Department of Agriculture (USDA) released a Deregulation Evaluation of Established Pests (DEEP) report that proposed to change the status of Quadrastichus erythrinae to non-actionable. A pest rating proposal is required to determine future direction on this pest in California.

History & Status:

Background: Quadrastichus erythrinae is an emerging pest gall wasp that disfigures the leaves and young shoots of more than 60 species of coral trees (Erythrinia spp.)^1,2. It may be transported long distances when infested plants or plant parts such as fallen leaves are moved¹. Female wasps insert eggs inside young leaves and stem tissue¹. As larvae develop, they induce galls which cause leaves to curl and shoots to become swollen¹. Larvae pupate inside leaves and stems and adults chew their way out as they emerge¹. Heavy infestations can cause defoliation and death of trees¹. Quadrastichus erythrinae was first found in Hawaii in 2005 and within 2 years caused 95% mortality of Erythrina trees¹.

Worldwide Distribution: Quadrastichus erythrinae is believed to be native to Africa¹. From there it has spread through much of Asia and the Pacific islands including Hawaii¹. In the Americas it is established in Brazil, Guadeloupe, Martinique, and Florida¹.

Official Control: Quadrastichus erythrinae is listed as a harmful organism by China, but is not known to be under official control in any other states or nations³.

California Distribution: Quadrastichus erythrinae has never been found in the environment of California.

California Interceptions: Quadrastichus erythrinae has never been intercepted in California.

The risk Quadrastichus erythrinae (Erythrina gall wasp) would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: The current distribution of Quadrastichus erythrinae corresponds to USDA Plant Hardiness Zones 10-13. This indicates that the pest is likely to be limited to the warmest parts of southern California. Quadrastichus erythrinae receives a Low (1) in this category.

Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

– Low (1) Not likely to establish in California; or likely to establish in very limited areas.

– Medium (2) may be able to establish in a larger but limited part of California.

– High (3) likely to establish a widespread distribution in California.

2) Known Pest Host Range: Quadrastichus erythrinae is only known to feed on coral trees in the genus Erythrina. It receives a Low (1) in this category.

Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.

– Medium (2) has a moderate host range.

– High (3) has a wide host range.

3) Pest Dispersal Potential: Quadrastichus erythrinae has a high reproductive rate. Each female carries an average of 320 eggs and can complete a life cycle in 20 days¹. These gall wasps may be transported long distances when infested plants or plant parts are moved and disperse locally by flying, wind, or by hitchhiking on clothing, animals, or equipment¹. Quadrastichus erythrinae receives a High (3) in this category.

Evaluate the natural and artificial dispersal potential of the pest. Score:

– Low (1) does not have high reproductive or dispersal potential.

– Medium (2) has either high reproductive or dispersal potential.

– High (3) has both high reproduction and dispersal potential.

4) Economic Impact: If Quadrastichus erythrinae were to establish in California it is not expected to lower any crop yields. It may reduce the value of Erythrina nursery stock and increase production costs of those trees. The gall wasp is not expected to disrupt any markets, change cultural practices, vector other organisms, injure animals, or interfere with water supplies. Quadrastichus erythrinae receives a Low (1) in this category.

Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.

B. The pest could lower crop value (includes increasing crop production costs).

C. The pest could trigger the loss of markets (includes quarantines).

D. The pest could negatively change normal cultural practices.

E. The pest can vector, or is vectored, by another pestiferous organism.

F. The organism is injurious or poisonous to agriculturally important animals.

G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.

– Medium (2) causes 2 of these impacts.

– High (3) causes 3 or more of these impacts.

5) Environmental Impact: Quadrastichus erythrinae is not expected to lower biodiversity, disrupt natural communities, or change ecosystem practices. It is not likely to directly affect threatened or endangered species or disrupt critical habitats. It may trigger additional treatment programs in the nursery industry and by residents who wish to save their coral trees. Coral trees are grown as ornamentals in southern California and may be extirpated by Quadrastichus erythrinae. Erythrina gall wasp receives a High (3) in this category.

Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.

B. The pest could directly affect threatened or endangered species.

C. The pest could impact threatened or endangered species by disrupting critical habitats.

D. The pest could trigger additional official or private treatment programs.

E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.

– Medium (2) causes one of the above to occur.

– High (3) causes two or more of the above to occur.

Consequences of Introduction to California for Quadrastichus erythrinae (Erythrina gall wasp): Medium (9)

Add up the total score and include it here.

–Low = 5-8 points

–Medium = 9-12 points

–High = 13-15 points

6) Post Entry Distribution and Survey Information: Quadrastichus erythrinae has never been found in California and receives a Not established (0) in this category.

Evaluate the known distribution in California. Only official records identified by a taxonomic expert and supported by voucher specimens deposited in natural history collections should be considered. Pest incursions that have been eradicated, are under eradication, or have been delimited with no further detections should not be included.

–Not established (0) Pest never detected in California, or known only from incursions.

–Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).

–Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.

–High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

Final Score:

The final score is the consequences of introduction score minus the post entry distribution and survey information score: Medium (9)

Uncertainty:

There have not been any surveys for Quadrastichus erythrinae in California.

Conclusion and Rating Justification:

Quadrastichus erythrinae has never been found in California. However, if it were to establish in the state its effects are likely to be limited to coral trees in the nursery industry and southern California landscape. A “B” rating is justified.

References:

¹CABI Invasive Species Compendium. Datasheet on Quadrastichus erythrinae (Erythrina gall wasp). http://www.cabi.org/isc/datasheet/46220

² Baez, Ignacio. DEEP Report Quadrastichus erythrinae Kim: Erythrina gall wasp. Deregulation Evaluation of Established Pests (DEEP). Plant Epidemiology and Risk Analysis Lab. Center for Plant Health Science and Technology.

³ USDA Phytosanitary Certificate Issuance & Tracking System (PCIT) Phytosanitary Export Database (PExD). https://pcit.aphis.usda.gov/pcit/

Responsible Party:

Jason Leathers, 1220 N Street, Sacramento, CA, 95814, (916) 654-1211, plant.health[@]cdfa.ca.gov.

Comment Format:

♦ Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s) being commented on, as shown below.

Example Comment:

Consequences of Introduction: 1. Climate/Host Interaction: [Your comment that relates to “Climate/Host Interaction” here.]

♦ Posted comments will not be able to be viewed immediately.

♦ Comments may not be posted if they:

Contain inappropriate language which is not germane to the pest rating proposal;

Contains defamatory, false, inaccurate, abusive, obscene, pornographic, sexually oriented, threatening, racially offensive, discriminatory or illegal material;

Violates agency regulations prohibiting sexual harassment or other forms of discrimination;

Violates agency regulations prohibiting workplace violence, including threats.

♦ Comments may be edited prior to posting to ensure they are entirely germane.

♦ Posted comments shall be those which have been approved in content and posted to the website to be viewed, not just submitted.

Pest Rating: B

Posted by ls

Hemiptera, Insects, Mites & Earthworms

Radionaspis indica (Marlatt) | Mango Scale

January 15, 2016 Jason Leathers

California Pest Rating for

Radionaspis indica (Marlatt): Mango Scale

Hemiptera: Diaspididae

Pest Rating: B

PEST RATING PROFILE

Initiating Event:

Since 2005 Radionaspis indica has been regularly intercepted on mango fruit by CDFA’s border stations and dog teams. This scale insect presently has a temporary rating of “Q”. A pest rating proposal is needed to establish a permanent pest rating.

History & Status:

Background: Radionaspis indica is a monophagous scale insect that feeds on the trunk, branches, and buds of mango trees (Mangifera indica (Anacardiaceae)). Severe infestations can cause cracking of bark, exudation of sap, and decline of branches². Radionaspis indica may rapidly disperse long distances in the trade of infested mango fruit or nursery stock.

Worldwide Distribution: Radionaspis indica may be native to India and is also found in Indonesia, the Federated States of Micronesia, Palau, Cape Verde, Senegal, Cuba, the British Virgin Islands, the Dominican Republic, Jamaica, and Panama³. In the United States the scale is found in Hawaii, Florida, and Puerto Rico³. Regular interceptions of the scale on mangos from Mexico suggest that it is established in that country.

Official Control: Radionaspis indica is not known to be under official control in any states or nations.

California Distribution: Radionaspis indica has never been found in the environment of California.

California Interceptions: Between January 1, 2005 and December 31, 2015 Radionaspis indica was intercepted 69 times on mango fruit by CDFA’s border stations and dog teams. It was also intercepted once on papaya.

The risk Radionaspis indica (mango scale) would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Mango trees require warm, dry weather to set fruit. In California the best locations are away from immediate marine influences in the deserts, foothills, and the warmest cove locations of the California Central Valley^{4,5, 6}. Mango trees are also sometimes grown as ornamental plants in urban environments and are present in the nursery industry. Radionaspis indica is expected to be able to establish in all of these environments. It receives a Medium(2) in this category.

Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

– Low (1) Not likely to establish in California; or likely to establish in very limited areas.

– Medium (2) may be able to establish in a larger but limited part of California.

– High (3) likely to establish a widespread distribution in California.

2) Known Pest Host Range: Radionaspis indica only feeds on mango and receives a Low(1) in this category.

Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.

– Medium (2) has a moderate host range.

– High (3) has a wide host range.

3) Pest Dispersal Potential: Armored scales have high reproductive potential. Mango fruit is not considered to be a good pathway for dispersal of Radionaspis indica due the limited mobility of female armored scales and crawlers and the species’ limited host range. However, the scales have high dispersal potential because they are able to disperse long distances rapidly on nursery stock and are able to disperse to any nearby trees by crawling, by wind, or by hitchhiking on clothing, equipment, or other animals. Radionaspis indica receives a High(3) in this category.

Evaluate the natural and artificial dispersal potential of the pest. Score:

– Low (1) does not have high reproductive or dispersal potential.

– Medium (2) has either high reproductive or dispersal potential.

– High (3) has both high reproduction and dispersal potential.

4) Economic Impact: California growers produce between 250,000 and 4,000,000 pounds of mango annually⁶. This is a high value commodity produced for local sales at specialty markets and demand is increasing⁶. California grown mangos are generally produced organically⁵. If Radionaspis indica were to enter California and become established in groves it could potentially reduce yields of this crop if heavy infestations cause branch dieback². Furthermore, the scale has potential to both lower crop value by disfiguring fruit and nursery stock with its presence and increase production costs by triggering new chemical treatments. Radionaspis indica receives a Medium(2) in this category.

Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.

B. The pest could lower crop value (includes increasing crop production costs).

C. The pest could trigger the loss of markets (includes quarantines).

D. The pest could negatively change normal cultural practices.

E. The pest can vector, or is vectored, by another pestiferous organism.

F. The organism is injurious or poisonous to agriculturally important animals.

G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.

– Medium (2) causes 2 of these impacts.

– High (3) causes 3 or more of these impacts.

5) Environmental Impact: Radionaspis indica is not expected to lower biodiversity, disrupt natural communities, or change ecosystem processes. The scale is not expected to feed on any endangered or threatened species or disrupt critical habitats. It is possible that its entry could trigger new treatment programs in orchards and nurseries and by residents who find infested trees unsightly. The scale is not expected significantly impact cultural practices, home/urban gardening, or ornamental plantings. Radionaspis indica receives a Medium(2) in this category.

Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.

B. The pest could directly affect threatened or endangered species.

C. The pest could impact threatened or endangered species by disrupting critical habitats.

D. The pest could trigger additional official or private treatment programs.

E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.

– Medium (2) causes one of the above to occur.

– High (3) causes two or more of the above to occur.

**Consequences of Introduction to California for Radionaspis indica (mango scale): Medium(10).**

Add up the total score and include it here.

–Low = 5-8 points

–Medium = 9-12 points

–High = 13-15 points

6) Post Entry Distribution and Survey Information: Radionaspis indica has never been found in California and receives a Not established(0) in this category.

–Not established (0) Pest never detected in California, or known only from incursions.

–Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).

–Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.

–High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

Final Score:

The final score is the consequences of introduction score minus the post entry distribution and survey information score: Medium(10)

Uncertainty:

It is possible that sometimes the presence of Radionaspis indica on fruit is indicative of home-grown mangos that have not been produced under commercial phytosanitary safeguards. Any failure to take action on Radionaspis indica infested fruit may increase the risk of introducing exotic fruit flies and other more damaging pests into California.

Conclusion and Rating Justification:

The impacts of the entry of Radionaspis indica into California are expected to be limited to mango groves, nurseries, and scattered ornamental plantings. Nevertheless, this scale insect may have significant economic and environmental impacts to this growing industry. A “B” rating is justified.

References:

¹Litz, Richard E. 2009. The Mango: Botany, Production, and Uses. CABI. 680pp. http://books.google.com/books?id=oloEhPYqE8QC&dq=Radionaspis+indica&source=gbs_navlinks_s

²Peña, Jorge E. 1994. Update on status of pests of tropical fruit crops in south Florida. Proc. Fla. State Hort. Soc. 107: 340-342. http://fshs.org/proceedings-o/1994-vol-107/340-342%20%28PENA%29.pdf

³ Ben-Dov, Y. (2014) ScaleNet, Radionaspis indica. Accessible online at: http://www.sel.barc.usda.gov/catalogs/diaspidi/Radionaspisindica.htm

⁴Grown in California website. Mango fruit facts page. http://www.grownincalifornia.com/fruit-facts/mango-facts.html

⁵Marks, Michael. 2013. Mango orchards in California? San Jose Mercury News. http://www.mercurynews.com/food-wine/ci_24089949/mango-orchards-california

⁶Karp, David. 2014. Mango madness. Sunset. http://www.sunset.com/travel/california/mango-madness

Responsible Party:

Jason Leathers, 1220 N Street, Sacramento, CA, 95814, (916) 654-1211, plant.health[@]cdfa.ca.gov.

Comment Format:

♦ Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s) being commented on, as shown below.

Example Comment:

Consequences of Introduction: 1. Climate/Host Interaction: [Your comment that relates to “Climate/Host Interaction” here.]

♦ Posted comments will not be able to be viewed immediately.

♦ Comments may not be posted if they:

Contain inappropriate language which is not germane to the pest rating proposal;

Contains defamatory, false, inaccurate, abusive, obscene, pornographic, sexually oriented, threatening, racially offensive, discriminatory or illegal material;

Violates agency regulations prohibiting sexual harassment or other forms of discrimination;

Violates agency regulations prohibiting workplace violence, including threats.

♦ Comments may be edited prior to posting to ensure they are entirely germane.

♦ Posted comments shall be those which have been approved in content and posted to the website to be viewed, not just submitted.

Pest Rating: B

Posted by ls

Hemiptera, Insects, Mites & Earthworms

Acanthococcus lagerstroemiae (Kuwana) | Crapemyrtle Scale

January 15, 2016 Jason Leathers

California Pest Rating for

Acanthococcus lagerstroemiae (Kuwana): Crapemyrtle Scale

Synonym: Eriococcus lagerstroemiae

Hemiptera: Eriococcidae

Pest Rating: A

PEST RATING PROFILE

Initiating Event:

In July 2015 the United States Department of Agriculture (USDA) inquired about California’s position on deregulating Eriococcus lagerstroemiae (Acanthococcus lagerstroemiae). A pest rating proposal is required to determine a permanent pest rating.

History & Status:

Background: Acanthococcus lagerstroemiae is a scale insect that feeds on the branches, twigs, trunk, stems, and leaves of its host-plants¹. It also feeds on the fruit of persimmon¹. Heavy infestations of the scale are not known to be fatal to trees but they do have significant aesthetic impacts that often lead to host removal¹. Layers of the scale on plants lead to extensive honeydew deposits, growth of sooty mold, dieback, decline, and decrease in the number and size of flowers¹. The sooty mold turns trunks, leaves, and twigs charcoal black¹. Known hosts of the scale include: Buxaceae: Korean boxwood (Buxus microphylla koreana²); Combretaceae: axlewood (Anogeiussus latifolia²), Anogeiussus sp.²; Ebenaceae: persimmon (Diospyros kaki²); Euphobiaceae: food wrapper plant (Mallotus japonicas²), needlebush (Glochidion puberum²); Fabaceae: Dalbergia sp.², soybean (Glycine max²); Lythraceae: crapemyrtle (Lagerstroemia indica²); Japanese crapemyrtle (Lagerstroemia japonica²), giant crapemyrtle (Lagerstsoemia flosreginae²); Moraceae: fig (Ficus carica²); Myrtaceae: Myrtus sp.²; Oleaceae: border privet (Ligustrum obtusifolium²); Punicaceae: pomegranate (Punica granatum²); Rosaceae: paradise apple (Malus pumila²); Chinese quince (Pseudocydonia sp.¹); Rubus sp.; Ulmaceae: Chinese hackberry (Celtis sinensis). The primary hosts are considered to be crapemyrtle, persimmon, Chinese quince, and pomegranate¹. Acanthococcus lagerstroemiae may be transported long distances when infested plants or fresh plant parts are moved.

Worldwide Distribution: Acanthococcus lagerstroemiae is native to China, India, Japan, South Korea, and possibly Mongolia¹. It was found in Texas in 2004. Since then it has spread throughout eastern Texas and to four counties in Arkansas, seven in Louisiana, five in Oklahoma, one in Tennessee, one in Virginia, and one in Mississippi¹.

Official Control: Acanthococcus lagerstroemiae is not known to be under official control in any other states or nations³. However, the USDA proposal would keep the scale actionable in Hawaii¹.

California Distribution: Acanthococcus lagerstroemiae has never been found in California.

California Interceptions: Acanthococcus lagerstroemiae has never been intercepted by CDFA.

The risk Acanthococcus lagerstroemiae (Crapemyrtle scale) would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Acanthococcus lagerstroemiae is expected to establish throughout plant hardiness zones 6-10¹. This corresponds to almost all of California. Host plants of the scale are grown throughout the state as ornamentals and crops. Crapemyrtle scale is likely to establish a widespread distribution in California and receives a High (3) in this category.

Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

– Low (1) Not likely to establish in California; or likely to establish in very limited areas.

– Medium (2) may be able to establish in a larger but limited part of California.

– High (3) likely to establish a widespread distribution in California.

2) Known Pest Host Range: Acanthococcus lagerstroemiae is known to feed on a variety of plants in twelve families, many of which are widely cultivated in California. It receives a Medium (2) in this category.

Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.

– Medium (2) has a moderate host range.

– High (3) has a wide host range.

3) Pest Dispersal Potential: Acanthococcus lagerstroemiae has 2-4 generations per year and each adult female lays an average of 220 eggs¹. The scales may disperse long distances when infested plants or fresh plant parts are moved. They may also be spread by wind or by hitchhiking on plants, animals, or equipment. Crapemyrtle scale receives a High (3) in this category.

Evaluate the natural and artificial dispersal potential of the pest. Score:

– Low (1) does not have high reproductive or dispersal potential.

– Medium (2) has either high reproductive or dispersal potential.

– High (3) has both high reproduction and dispersal potential.

4) Economic Impact: In Asia Acanthococcus lagerstroemiae is the major pest of crapemyrtle trees, and is also a serious pest of pomegranate and persimmon trees. If this scale insect were to establish in California it is expected to lower yields in pomegranate and persimmon groves. It is also likely to lower the value of persimmon fruit and all host nursery stock. Since the USDA has proposed to keep crapemyrtle scale actionable in Hawaii, this scale is also likely to disrupt markets for California fruit and nursery stock if it were to establish in the state. Crapemyrtle scale is not expected to change cultural practices, vector other organisms, injure animals, or interfere with water supplies. Acanthococcus lagerstroemiae receives a High (3) in this category.

Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.

B. The pest could lower crop value (includes increasing crop production costs).

C. The pest could trigger the loss of markets (includes quarantines).

D. The pest could negatively change normal cultural practices.

E. The pest can vector, or is vectored, by another pestiferous organism.

F. The organism is injurious or poisonous to agriculturally important animals.

G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.

– Medium (2) causes 2 of these impacts.

– High (3) causes 3 or more of these impacts.

5) Environmental Impact: If Acanthococcus lagerstroemiae were to establish in California it is not likely to lower biodiversity, disrupt natural communities, or change ecosystem processes. It is not likely to directly affect threatened or endangered species or disrupt critical habitats. It is very likely to trigger new treatment programs in orchards and by residents who find infested plants unsightly. Crapemyrtle, pomegranate, and persimmon trees are common ornamentals in California and are likely to be significantly affected by this pest. Many of the host trees have been removed from areas in Texas where the scale has established¹. Crapemyrtle scale receives a High (3) in this category.

Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.

B. The pest could directly affect threatened or endangered species.

C. The pest could impact threatened or endangered species by disrupting critical habitats.

D. The pest could trigger additional official or private treatment programs.

E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.

– Medium (2) causes one of the above to occur.

– High (3) causes two or more of the above to occur.

**Consequences of Introduction to California for Acanthococcus lagerstroemiae (Crapemyrtle Scale): High (14)**

Add up the total score and include it here.

–Low = 5-8 points

–Medium = 9-12 points

–High = 13-15 points

6) Post Entry Distribution and Survey Information: Acanthococcus lagerstroemiae has not been found in California. The severe aesthetic impacts attributed to infestations of the scale and ease of detection since it is the only bark scale known to occur on crapemyrtle¹ make it unlikely that this pest is present anywhere in California. Crapemyrtle scale receives a Not established (0) in this category.

–Not established (0) Pest never detected in California, or known only from incursions.

–Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).

–Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.

–High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

Final Score:

The final score is the consequences of introduction score minus the post entry distribution and survey information score: High (14)

Uncertainty:

It is possible that this scale could colonize additional host plants in California.

Conclusion and Rating Justification:

Acanthococcus lagerstroemiae has not been found in California and it is expected to have significant economic and environmental impacts if it were to establish in the state. An “A” rating is justified.

References:

¹Miller, Leah. 2015. NPAG Report Eriococcus lagerstroemiae Kuwana: crapemyrtle scale. New Pest Advisory Group (NPAG).

² SEL Catalogue Query Results/ScaleNet: Acanthococcus lagerstroemiae (Kuwana). http://www.sel.barc.usda.gov/catalogs/eriococc/Acanthococcuslagerstroemiae.htm

³ USDA Phytosanitary Certificate Issuance & Tracking System (PCIT) Phytosanitary Export Database (PExD). https://pcit.aphis.usda.gov/pcit/

Responsible Party:

Jason Leathers, 1220 N Street, Sacramento, CA, 95814, (916) 654-1211, plant.health[@]cdfa.ca.gov.

Comment Format:

♦ Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s) being commented on, as shown below.

Example Comment:

Consequences of Introduction: 1. Climate/Host Interaction: [Your comment that relates to “Climate/Host Interaction” here.]

♦ Posted comments will not be able to be viewed immediately.

♦ Comments may not be posted if they:

Contain inappropriate language which is not germane to the pest rating proposal;

Contains defamatory, false, inaccurate, abusive, obscene, pornographic, sexually oriented, threatening, racially offensive, discriminatory or illegal material;

Violates agency regulations prohibiting sexual harassment or other forms of discrimination;

Violates agency regulations prohibiting workplace violence, including threats.

♦ Comments may be edited prior to posting to ensure they are entirely germane.

♦ Posted comments shall be those which have been approved in content and posted to the website to be viewed, not just submitted.

Pest Rating: A

Posted by ls

Hemiptera, Insects, Mites & Earthworms

Macrohomotoma gladiata (Kuwayama) | Curtain Fig Psyllid

January 15, 2016 Jason Leathers

California Pest Rating for

Macrohomotoma gladiata (Kuwayama): Curtain Fig Psyllid

Hemiptera: Psyllidae

Pest Rating: B

PEST RATING PROFILE

Initiating Event:

On August 28, 2015 Dr. Alessandra Rung identified psyllids collected in a nursery in Orange County as Macrohomotoma cf. gladiata. A pest rating proposal is required to assign a permanent pest rating.

History & Status:

Background: Macrohomotoma gladiata is a psyllid that feeds on the new shoots of several varieties of ornamental Ficus trees¹. Adult psyllids lay eggs on new leaves of twigs and withered bracts¹. As the nymphs feed shoots become deformed, stop developing, and eventually die¹. Leaves become covered in white waxy secretions which facilitate the development of sooty-mold². The main hosts of the psyllid are curtain fig (Ficus microcarpa) and Cuban-laurel (Ficus retusa)¹. There are also questionable records from Indian banyan (Ficus benghalensis) and rusty-leaf fig (Ficus microphylla)¹.

Worldwide Distribution: Macrohomotoma gladiata is native to China, Taiwan, and Japan where it is not considered to be a pest¹. It was first found in Europe in the Balearic Islands in 2009 where it emerged as a pest and has since spread to mainland Spain (2010) and Italy (2011)¹. It has not previously been found in North or South America.

Official Control: Macrohomotoma gladiata is not known to be under official control in any other states or nations.

California Distribution: Macrohomotoma gladiata has been found at several residential and commercial properties in Anaheim, Orange County feeding on curtain fig (Ficus microcarpa).

California Interceptions: Macrohomotoma gladiata has been found in four nurseries in Orange County feeding on Ficus microcarpa.

The risk Macrohomotoma gladiata (curtain fig psyllid) would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Ficus microcarpa is a popular ornamental that grows in USDA plant hardiness zones 9-11, corresponding with much of the San Joaquin Valley, Coastal, and Southern California. Macrohomotoma gladiata is expected to be able to establish throughout these regions wherever suitable host plants are found. It receives a High (3) in this category.

Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

– Low (1) Not likely to establish in California; or likely to establish in very limited areas.

– Medium (2) may be able to establish in a larger but limited part of California.

– High (3) likely to establish a widespread distribution in California.

2) Known Pest Host Range: Macrohomotoma gladiata is only known to feed on several varieties of Ficus trees and receives a Low (1) in this category.

Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.

– Medium (2) has a moderate host range.

– High (3) has a wide host range.

3) Pest Dispersal Potential: Psyllids have high reproductive rates and can disperse locally by flying. They may also be transported long distances when infested plants or leaves are moved or by hitchhiking on clothing, equipment, or animals. Macrohomotoma gladiata receives a High (3) in this category.

Evaluate the natural and artificial dispersal potential of the pest. Score:

– Low (1) does not have high reproductive or dispersal potential.

– Medium (2) has either high reproductive or dispersal potential.

– High (3) has both high reproduction and dispersal potential.

4) Economic Impact: Ficus microcarpa plants are a valuable component of the nursery industry. If Macrohomotoma gladiata were to establish in the environment of California it is likely to lower nursery yields of these plants and increase production costs. Due to the absence of this psyllid from the entirety of North America there could be disruptions to markets for California produced Ficus microcarpa nursery stock. Macrohomotoma gladiata receives a High (3) in this category.

Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.

B. The pest could lower crop value (includes increasing crop production costs).

C. The pest could trigger the loss of markets (includes quarantines).

D. The pest could negatively change normal cultural practices.

E. The pest can vector, or is vectored, by another pestiferous organism.

F. The organism is injurious or poisonous to agriculturally important animals.

G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.

– Medium (2) causes 2 of these impacts.

– High (3) causes 3 or more of these impacts.

5) Environmental Impact: If Macrohomotoma gladiata were to establish in the environment of California it is not expected to lower biodiversity, disrupt natural communities, or change ecosystem processes. It is not likely to directly affect threatened or endangered species or disrupt critical habitats. Its presence is likely to trigger new chemical treatments in the nursery industry and by residents who find infested plants unsightly. Ficus microcarpa trees are widely grown as ornamentals in California and are likely to be significantly impacted by this pest. Macrohomotoma gladiata receives a High (3) in this category.

Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.

B. The pest could directly affect threatened or endangered species.

C. The pest could impact threatened or endangered species by disrupting critical habitats.

D. The pest could trigger additional official or private treatment programs.

E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.

– Medium (2) causes one of the above to occur.

– High (3) causes two or more of the above to occur.

**Consequences of Introduction to California for Macrohomotoma gladiata (Curtain Fig Psyllid): High (13)**

Add up the total score and include it here.

–Low = 5-8 points

–Medium = 9-12 points

–High = 13-15 points

6) Post Entry Distribution and Survey Information: Macrohomotoma gladiata has only been found in the environment of Orange County and receives a Low (-1) in this category.

–Not established (0) Pest never detected in California, or known only from incursions.

–Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).

–Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.

–High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

Final Score:

The final score is the consequences of introduction score minus the post entry distribution and survey information score: Medium (12)

Uncertainty:

There have not been any recent surveys for this psyllid in California, so it may be more widespread. Over the last three years many new Ficus pests have been found in southern California including Ficus whitefly (Singhiella simplex), ficus eye-spot midge (Horidiplosis ficifolii), and Cuban-laurel thrips (Gynaikothrips uzeli). It is possible that new treatments that are already necessary for these other new pests will preclude some of the economic and environmental impacts from additional new pests such as Macrohomotoma gladiata. Alternatively, the psyllid might have a larger host range in California than has been documented elsewhere.

Conclusion and Rating Justification:

Macrohomotoma gladiata has been found in the environment of Orange County and is likely to have significant economic and environmental impacts as it expands its range in the state. A “B”-rating in justified.

References:

¹ Pedata, Paolo Alfonso, Daniel Burckhardt, and Donato Mancini. 2012. Severe infestations of the jumping plant-louse Macrohomotoma gladiata, a new species for Italy in urban Ficus plantations. Bulletin of Insectology 65(1): 95-98. http://www.bulletinofinsectology.org/pdfarticles/vol65-2012-095-098pedata.pdf

² Mifsud, D. and F. Porcelli. 2012. The psyllid Macrohomotoma gladiata Kuwayama, 1908 (Hemiptera: Psylloidea: Homotomidae): a Ficus pest recently introduced in the EPPO region. EPPO Bulletin 42(1): 161-164. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2338.2012.02544.x/abstract

Responsible Party:

Jason Leathers, 1220 N Street, Sacramento, CA, 95814, (916) 654-1211, plant.health[@]cdfa.ca.gov.

Comment Format:

♦ Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s) being commented on, as shown below.

Example Comment:

Consequences of Introduction: 1. Climate/Host Interaction: [Your comment that relates to “Climate/Host Interaction” here.]

♦ Posted comments will not be able to be viewed immediately.

♦ Comments may not be posted if they:

Contain inappropriate language which is not germane to the pest rating proposal;

Contains defamatory, false, inaccurate, abusive, obscene, pornographic, sexually oriented, threatening, racially offensive, discriminatory or illegal material;

Violates agency regulations prohibiting sexual harassment or other forms of discrimination;

Violates agency regulations prohibiting workplace violence, including threats.

♦ Comments may be edited prior to posting to ensure they are entirely germane.

♦ Posted comments shall be those which have been approved in content and posted to the website to be viewed, not just submitted.

Pest Rating: B

Posted by ls

Hemiptera, Insects, Mites & Earthworms

Tarophagus colocasiae (Matsumura) | Taro Planthopper

January 15, 2016 Jason Leathers

California Pest Rating for

Tarophagus colocasiae (Matsumura): Taro Planthopper

Hemiptera: Delphacidae

Pest Rating: B

PEST RATING PROFILE

Initiating Event:

Tarophagus colocasiae is commonly intercepted by California’s high risk programs. This planthopper is currently assigned a temporary rating of “Q” and is therefore in need of a permanent pest rating.

History & Status:

Background: Tarophagus colocasiae is a planthopper that is considered a serious pest of taro (Colocasia esculenta)¹. The planthopper feeds by sucking sap and/or xylem from the plant tissue¹. Feeding produces honeydew, sooty mold, and necrotic areas on leaves and discoloration of bark on stems¹. Heavy infestations may cause stunting and/or wilting of the taro plants. Taro planthopper is also reported to vector alomae and bobone diseases, which are caused by rhabdoviruses, between taro plants. The planthopper may spread long distances by the movement of infested taro plants, leaves, or roots.

Worldwide Distribution: Tarophagus colocasiae is widespread in Southeast Asia and the Pacific islands¹. It has been present in Hawaii since at least 1930. The planthopper was confirmed to be present in Florida in June 2015 and is likely established in both Jamaica and Cuba⁴.

Official Control: Tarophagus colocasiae is not listed as a quarantine pest by any other states or nations². However, Tarophagus proserpina is listed as a quarantine pest by Japan and Korea and that species may be a synonym of T. colocasiae.

California Distribution: Tarophagus colocasiae has never been found in the environment of California.

California Interceptions: Between January 1, 2000 and January 6, 2015, Tarophagus colocasiae was intercepted 133 times on consignments from Hawaii. 127 of the interceptions were on taro. The remainder were on betel leaf (1), ginger (1), galanga (2), and sweet potato (2).

The risk Tarophagus colocasiae (taro planthopper) would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Taro grows in USDA plant hardiness zones 8 through 11 and is grown in gardens and small-scale commercial farms in Fresno and Sacramento California³. Tarophagus colocasiae is expected to be able to establish wherever these plants are grown. It receives a Medium (2) in this category.

Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

– Low (1) Not likely to establish in California; or likely to establish in very limited areas.

– Medium (2) may be able to establish in a larger but limited part of California.

– High (3) likely to establish a widespread distribution in California.

2) Known Pest Host Range: Tarophagus colocasiae is only known to feed on taro and related aroids. It receives a Low (1) in this category.

Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.

– Medium (2) has a moderate host range.

– High (3) has a wide host range.

3) Pest Dispersal Potential: Taro planthoppers may be moved long distances when infested taro plants, leaves, or roots are moved. However, their wings do not fully develop and they are not considered to be good fliers. Planthoppers have high reproductive rates. Tarophagus colocasiae receives a High (3) in this category.

Evaluate the natural and artificial dispersal potential of the pest. Score:

– Low (1) does not have high reproductive or dispersal potential.

– Medium (2) has either high reproductive or dispersal potential.

– High (3) has both high reproduction and dispersal potential.

4) Economic Impact: If Tarophagus colocasiae were to establish in California it would be likely to lower the yield of commercial taro farms and gardens. The planthopper would also be likely to increase crop production costs. Taro leafhopper may also vector diseases between taro plants. It receives a High (3) in this category.

Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.

B. The pest could lower crop value (includes increasing crop production costs).

C. The pest could trigger the loss of markets (includes quarantines).

D. The pest could negatively change normal cultural practices.

E. The pest can vector, or is vectored, by another pestiferous organism.

F. The organism is injurious or poisonous to agriculturally important animals.

G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.

– Medium (2) causes 2 of these impacts.

– High (3) causes 3 or more of these impacts.

5) Environmental Impact: Tarophagus colocasiae is not expected to lower biodiversity, disrupt natural communities, or change ecosystem processes. Taro planthopper is not expected to directly affect threatened or endangered species or disrupt critical habitats. The planthopper may trigger additional treatment programs by gardeners and growers of commercial taro. The planthopper may also significantly impact taro plants in home/urban gardens. Taro planthopper receives a High (3) in this category.

Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.

B. The pest could directly affect threatened or endangered species.

C. The pest could impact threatened or endangered species by disrupting critical habitats.

D. The pest could trigger additional official or private treatment programs.

E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.

– Medium (2) causes one of the above to occur.

– High (3) causes two or more of the above to occur.

Consequences of Introduction to California for Tarophagus colocasiae (Taro Planthopper): Medium(12)

Add up the total score and include it here.

–Low = 5-8 points

–Medium = 9-12 points

–High = 13-15 points

6) Post Entry Distribution and Survey Information: Tarophagus colocasiae has never been found in the environment of California and receives a Not established (0) in this category.

–Not established (0) Pest never detected in California, or known only from incursions.

–Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).

–Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.

–High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

Final Score:

The final score is the consequences of introduction score minus the post entry distribution and survey information score: Medium(12)

Uncertainty:

Tarophagus colocasiae is frequently intercepted. Presumably, the planthopper sometimes escapes detection and enters California. There have not been any formal surveys for the pest in the state, so it is possible that it may have established in some locations.

Conclusion and Rating Justification:

Tarophagus colocasiae has never been found in the environment of California. However, if it were to enter the state economic and environmental impacts would be limited to taro plants in home gardens and small-scale commercial farms. A “B” rating is justified.

References:

¹CABI Plantwise Knowledge Bank. http://www.plantwise.org/KnowledgeBank/Datasheet.aspx?dsid=52786

² USDA Phytosanitary Certificate Issuance & Tracking System (PCIT) Phytosanitary Export Database (PExD). https://pcit.aphis.usda.gov/pcit/

³Robinson, Ramona and Cara Allen. 2014. Taro root (Colocasia escuelenta) reported naturalizing in California. California Department of Parks and Recreation. http://www.cal-ipc.org/symposia/archive/pdf/2014/Poster2014_Robison.pdf

⁴ Halbert, Susan E. and Charles R. Bartlett. The taro planthopper, Tarophagus colocasiae (Matsumura), a new delphacid planthopper in Florida. Florida Department of Agriculture and Consumer Services Pest Alert. http://www.freshfromflorida.com/Divisions-Offices/Plant-Industry/Plant-Industry-Publications/Pest-Alerts/Tarophagus-colocasiae

Responsible Party:

Jason Leathers, 1220 N Street, Sacramento, CA, 95814, (916) 654-1211, plant.health[@]cdfa.ca.gov.

Comment Format:

♦ Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s) being commented on, as shown below.

Example Comment:

Consequences of Introduction: 1. Climate/Host Interaction: [Your comment that relates to “Climate/Host Interaction” here.]

♦ Posted comments will not be able to be viewed immediately.

♦ Comments may not be posted if they:

Contain inappropriate language which is not germane to the pest rating proposal;

Contains defamatory, false, inaccurate, abusive, obscene, pornographic, sexually oriented, threatening, racially offensive, discriminatory or illegal material;

Violates agency regulations prohibiting sexual harassment or other forms of discrimination;

Violates agency regulations prohibiting workplace violence, including threats.

♦ Comments may be edited prior to posting to ensure they are entirely germane.

♦ Posted comments shall be those which have been approved in content and posted to the website to be viewed, not just submitted.

Pest Rating: B

Posted by ls

Diptera, Insects, Mites & Earthworms

Zaprionus indianus Gupta: Striped Vinegar Fly

December 16, 2015 Jason Leathers

California Pest Rating for

Zaprionus cf. indianus Image Citation: Darren J. Obbard (obbardlab) — *Zaprionus cf. indianus*
Image Citation: Darren J. Obbard (obbardlab)

Zaprionus indianus Gupta: Striped Vinegar Fly

Diptera: Drosophilidae

Pest Rating: B

PEST RATING PROFILE

Initiating Event:

On July 29, 2015 Dr. Stephen Gaimari confirmed the identification of Zaprionus indianus from a sample submitted by a resident in Los Angeles County. This find was soon confirmed by official samples. A pest rating proposal is required to assign a permanent pest rating.

History & Status:

Background: Zaprionus indianus is a generalist small fly that feeds on fallen fruit and fruit on the tree¹. In most host species, fruit damage is necessary to allow the fly access to fruit¹. However, it is able to attack undamaged figs by laying eggs at the ostiole¹. Infestations of Zaprionus indianus may reduce the yield of commercial fig by 40-80%¹. Striped vinegar fly may be transported long distances when infested fruit is moved or by researchers who study model organisms in the family Drosophilidae.

Worldwide Distribution: Zaprionus indianus is native to Africa, the Middle East, and southern Eurasia¹. It was first found in Brazil in 1999 and rapidly spread through that nation and Uruguay¹. It was then found in Mexico in 2002², Panama in 2003², Florida in 2005¹, Pennsylvania in 2011³, Virginia in 2012², and Utah and Oklahoma in 2015⁸. It has also been reported in other states but records are not known to be verifiable (Michigan, Texas, Arizona, California, Mississippi, Louisiana, South Carolina, Wisconsin, and Connecticut)^6,9. One author reports that this fly is established “throughout the western USA”⁷.

Official Control: Zaprionus indianus is listed as a harmful organism by Japan and the Republic of Korea⁴.

California Distribution: Zaprionus indianus is only confirmed to be established in Los Angeles County.

California Interceptions: Zaprionus indianus has never been intercepted by CDFA.

The risk Zaprionus indianus (Striped vinegar fly) would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Zaprionus indianus has a widespread distribution in eastern North America from Pennsylvania to Florida corresponding with much of California. Striped vinegar fly is likely to establish a widespread distribution in the state and receives a High (3) in this category.

Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

– Low (1) Not likely to establish in California; or likely to establish in very limited areas.
– Medium (2) may be able to establish in a larger but limited part of California.
– High (3) likely to establish a widespread distribution in California.

2) Known Pest Host Range: Zaprionus indianus feeds on a wide variety of damaged fruit. The only undamaged fruit it is known to attack is figs. It receives a Low (1) in this category.

Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.
– Medium (2) has a moderate host range.
– High (3) has a wide host range.

3) Pest Dispersal Potential: Since it was first found in Brazil in 1999 Zaprionus indianus has rapidly colonized much of the Americas. It breeds continuously under favorable conditions and each female produces many offspring. It can be transported long distances when infested fruit is moved. Striped vinegar fly receives a High (3) in this category.

Evaluate the natural and artificial dispersal potential of the pest. Score:

– Low (1) does not have high reproductive or dispersal potential.
– Medium (2) has either high reproductive or dispersal potential.
– High (3) has both high reproduction and dispersal potential.

4) Economic Impact: California leads the nation in fig production. Growers in the state produce 96% of the nation’s figs on 7,300 acres for a total crop value of $23.1 million⁵ in 2013. If Zaprionus indianus were to establish in fig production areas it is likely to significantly reduce yields. In South America it is also reported to be an important pest of oranges and peaches but this is probably due to cultural practices where fruit is allowed to over-ripen on the tree^2,3. It has also been found to be abundant in eastern U.S. vineyards but has not been documented causing any economic damage^3,6. Zaprionus indianus is expected to increase crop production costs in fig orchards, as some fig growers in areas where the fly is established place a sticker over each fruit ostiole as a control measure³ or may treat. Zaprionus indianus also has the potential to disrupt fig and a wide variety of fresh fruit markets as both Japan and Korea list the fly as a harmful organism⁴. Striped vinegar fly receives a High (3) in this category.

Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.
B. The pest could lower crop value (includes increasing crop production costs).
C. The pest could trigger the loss of markets (includes quarantines).
D. The pest could negatively change normal cultural practices.
E. The pest can vector, or is vectored, by another pestiferous organism.
F. The organism is injurious or poisonous to agriculturally important animals.
G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.
– Medium (2) causes 2 of these impacts.
– High (3) causes 3 or more of these impacts.

5) Environmental Impact: If Zaprionus indianus were to establish in California it is not expected to lower biodiversity, disrupt natural communities, or change ecosystem processes. It is not likely to affect any threatened or endangered species or disrupt critical habitats. It may trigger new treatment programs in fig orchards and by residents who grow figs for consumption. Figs are grown in home/urban gardens and will be significantly impacted by this pest. Striped vinegar fly receives a High (3) in this category.

Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.
B. The pest could directly affect threatened or endangered species.
C. The pest could impact threatened or endangered species by disrupting critical habitats.
D. The pest could trigger additional official or private treatment programs.
E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.
– Medium (2) causes one of the above to occur.
– High (3) causes two or more of the above to occur.

**Consequences of Introduction to California for Zaprionus indianus (Striped Vinegar Fly): High (13)**

Add up the total score and include it here.

–Low = 5-8 points
–Medium = 9-12 points
–High = 13-15 points

6) Post Entry Distribution and Survey Information: Zaprionus indianus is confirmed to be established in Los Angeles County and is reported to be established in San Diego. It receives a Low (-1) in this category.

–Not established (0) Pest never detected in California, or known only from incursions.
–Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).
–Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.
–High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

Final Score:

The final score is the consequences of introduction score minus the post entry distribution and survey information score: Medium (12)

Uncertainty:

It is possible that Zaprionus indianus may be able to expand the range of undamaged fruit it feeds on beyond fig in California.

Conclusion and Rating Justification:

Zaprionus indianus has established a localized distribution in California and is expected to have significant economic and environmental impacts as it expands its range in California. Impacts are expected to be limited to fig. A “B” rating is justified.

References:

¹ Van der Linde, Kim, Gary J. Steck, Ken Hibbard, Jeffry S. Birdsley, Linette M. Alonso, and David Houle. 2006. First records of Zaprionus indianus (Diptera: Drosophilidae), a pest species on commercial fruits from Panama and the Untied States of America. Florida Entomologist 89(3):402-404. http://www.bioone.org/doi/pdf/10.1653/0015-4040%282006%2989%5B402%3AFROZID%5D2.0.CO%3B2

² Markow, Therese Ann, Giovanni Hanna, Juan R. Riesgo-Escobar, Aldo A. Tellez-Garcia, Maxi Polihronakis Richmond, Nestor O. Nazario-Yepiz, Mariana Ramierez Loustalot Laclette, Javier Carpinteyro-Ponce, and Edward Pfeiler. 2014. Population genetics and recent colonization history of the invasive drosophilid Zaprionus indianus in Mexico and Central America. Biological Invasions 16: 2427-2434. http://link.springer.com/article/10.1007%2Fs10530-014-0674-5#page-2

³ Joshi, Neelendra K., David J. Biddinger, Kathleen Demchak, Alan Deppen. 2014. First report of Zaprionus indianus (Diptera: Drosophilidae) in commercial fruits and vegetables in Pennsylvania. Journal of Insect Science http://jinsectscience.oxfordjournals.org/content/14/1/259

⁴ USDA Phytosanitary Certificate Issuance & Tracking System (PCIT) Phytosanitary Export Database (PExD). https://pcit.aphis.usda.gov/pcit/

⁵ California Department of Food & Agriculture. California Agricultural Production Statistics 2014 Report. http://www.cdfa.ca.gov/Statistics/PDFs/CropYearStats2013_NASS.pdf

⁶Sigler, Derrek. 2012. New fruit fly spreading across country. FGN Fruit Grower News. http://fruitgrowersnews.com/index.php/magazine/article/new-fruit-fly-spreading-across-country

⁷ Van der Linde, Kim. 2010. Zaprionus indianus: species identification and taxonomic position. Drosophila Information Service 93:95-98. http://www.ou.edu/journals/dis/DIS93/van%20der%20Linde%2095.pdf

⁸ Survey Status of Drosophilid Fig Fly – Zaprionus indianus. http://pest.ceris.purdue.edu/capsreview.php?code=IOAPAQA

⁹ Van det Linde, Kim. Zaprionus indianus: taxonomic position and species identification. http://www.kimvdlinde.com/professional/Zaprionus%20indianus.html

Responsible Party:

Jason Leathers, 1220 N Street, Sacramento, CA, 95814, (916) 654-1211, plant.health[@]cdfa.ca.gov.

Comment Format:

♦ Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s) being commented on, as shown below.

Example Comment:

Consequences of Introduction: 1. Climate/Host Interaction: [Your comment that relates to “Climate/Host Interaction” here.]

♦ Posted comments will not be able to be viewed immediately.

♦ Comments may not be posted if they:

Contain inappropriate language which is not germane to the pest rating proposal;

Contains defamatory, false, inaccurate, abusive, obscene, pornographic, sexually oriented, threatening, racially offensive, discriminatory or illegal material;

Violates agency regulations prohibiting sexual harassment or other forms of discrimination;

Violates agency regulations prohibiting workplace violence, including threats.

♦ Comments may be edited prior to posting to ensure they are entirely germane.

♦ Posted comments shall be those which have been approved in content and posted to the website to be viewed, not just submitted.

Pest Rating: B

Posted by ls

Hymenoptera, Insects, Mites & Earthworms

Ophelimus maskelli (Ashmead): Eucalyptus Gall Wasp

December 16, 2015 Jason Leathers

California Pest Rating for

Ophelimus maskelli (Ashmead): Eucalyptus Gall Wasp

Hymenoptera: Eulophidae

Pest Rating: C

PEST RATING PROFILE

Initiating Event:

Ophelimus maskelli has been found in the environment of southern California and is presently assigned a temporary rating of “Q”. A pest rating proposal is required to assign a permanent pest rating.

History & Status:

Background: Ophelimus maskelli is a species of wasp that induces galls on leaves of several species of Eucalyptus. Uncontrolled populations can cause severe leaf damage and early leaf drop¹.

Worldwide Distribution: Ophelimus maskelli is probably native to Australia. It was first found in the Mediterranean basin in Italy in 1999 and has since spread around the region¹. It has also been found in New Zealand, Indonesia, South Africa, and Vietnam¹. Ophelimus maskelli may be transported long distances when infested plants or fresh plant parts are moved.

Official Control: Ophelimus maskelli is not known to be under official control in any other states or nations.

California Distribution: Ophelimus maskelli is found in the environment of Riverside, San Diego, and Orange County¹. It is likely present in Los Angeles County.

California Interceptions: Ophelimus maskelli has been found in one nursery in Riverside County (PDR 331P06142763).

The risk Ophelimus maskelli (Eucalyptus gall wasp) would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Eucalyptus trees are commonly planted as ornamentals in southern and coastal California. Ophelimus maskelli is likely to establish wherever suitable hosts are found. It receives a Medium (2) in this category.

Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

2) Known Pest Host Range: Ophelimus maskelli is only known to feed on the leaves of Eucalyptus trees. It receives a Low (1) in this category.

Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.
– Medium (2) has a moderate host range.
– High (3) has a wide host range.

3) Pest Dispersal Potential: Ophelimus maskelli can build large populations quickly, indicating high reproductive potential. It may be transported long distances in infested plants or fresh plant parts. It receives a High (3) in this category.

Evaluate the natural and artificial dispersal potential of the pest. Score:

4) Economic Impact: Ophelimus maskelli is not expected to lower any crop yields. It may lower the value of Eucalyptus nursery stock by disfiguring plants with its presence. It is not expected to disrupt markets, change cultural practices, vector other organisms, or injure animals. Ophelimus maskelli receives a Low (1) in this category.

Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.
B. The pest could lower crop value (includes increasing crop production costs).
C. The pest could trigger the loss of markets (includes quarantines).
D. The pest could negatively change normal cultural practices.
E. The pest can vector, or is vectored, by another pestiferous organism.
F. The organism is injurious or poisonous to agriculturally important animals.
G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.
– Medium (2) causes 2 of these impacts.
– High (3) causes 3 or more of these impacts.

5) Environmental Impact: Ophelimus maskelli is not expected to lower biodiversity, disrupt natural communities, or change ecosystem processes. It is not expected to directly affect threatened or endangered species or disrupt critical habitats. It may trigger additional treatment programs in the nursery industry and by residents who find infested plants unsightly. Eucalyptus trees are common ornamentals and can be defoliated by this wasp. Ophelimus maskelli receives a High (3) in this category.

Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.
B. The pest could directly affect threatened or endangered species.
C. The pest could impact threatened or endangered species by disrupting critical habitats.
D. The pest could trigger additional official or private treatment programs.
E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.
– Medium (2) causes one of the above to occur.
– High (3) causes two or more of the above to occur.

**Consequences of Introduction to California for Ophelimus maskelli (Eucalyptus gall wasp): Medium (10)**

Add up the total score and include it here.

–Low = 5-8 points
–Medium = 9-12 points
–High = 13-15 points

6) Post Entry Distribution and Survey Information: Ophelimus maskelli is established in Riverside, San Diego, and Orange counties¹. It is probably also present in Los Angeles County. It receives a Medium (-2) in this category.

Final Score:

The final score is the consequences of introduction score minus the post entry distribution and survey information score: Low (8)

Uncertainty:

Ophelimus maskelli was widespread and abundant in southern California when it was first observed. It is likely much more widespread.

Conclusion and Rating Justification:

Ophelimus maskelli is widespread and abundant in the environment of southern California and is not under official control. Impacts are expected to be limited to disfigurement of Eucalyptus trees and possible increased insecticide use. A “C” rating is justified.

References:

¹ Burks, Roger A., Jason L. Mottern, Rebeccah Waterworth, and Timothy D. Paine. 2015. First report of the Eucalyptus gall wasp, Ophelimus maskelli (Hymenoptera: Eulophidae), an invasive pest on Eucalyptus, from the Western Hemisphere. Zootaxa 3926(3): 448-450.

Responsible Party:

Jason Leathers, 1220 N Street, Sacramento, CA, 95814, (916) 654-1211, plant.health[@]cdfa.ca.gov.

Comment Format:

♦ Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s) being commented on, as shown below.

Example Comment:

Consequences of Introduction: 1. Climate/Host Interaction: [Your comment that relates to “Climate/Host Interaction” here.]

♦ Posted comments will not be able to be viewed immediately.

♦ Comments may not be posted if they:

Contain inappropriate language which is not germane to the pest rating proposal;

Contains defamatory, false, inaccurate, abusive, obscene, pornographic, sexually oriented, threatening, racially offensive, discriminatory or illegal material;

Violates agency regulations prohibiting sexual harassment or other forms of discrimination;

Violates agency regulations prohibiting workplace violence, including threats.

♦ Comments may be edited prior to posting to ensure they are entirely germane.

♦ Posted comments shall be those which have been approved in content and posted to the website to be viewed, not just submitted.

Pest Rating: C

Posted by ls

Insects, Mites & Earthworms, Thysanoptera

Scirtothrips dorsalis Hood: (Chilli Thrips)

December 16, 2015 Jason Leathers

California Pest Rating for

Scirtothrips dorsalis Hood: (Chilli Thrips)

Thysanoptera: Thripidae

Pest Rating: B

PEST RATING PROFILE

Initiating Event:

In August 2015 infestations of Scirtothrips dorsalis were found at several residential properties in Orange County. A pest rating proposal is required to determine future direction on this pest.

History & Status:

Background: Scirtothrips dorsalis is a polyphagous thrips that is reported to feed on more than 200 plant species in 70 families³. Known hosts include economically important crops such as roses, chilies, grapes, citrus, avocado, tomato, and strawberry^1,2,3. The thrips has been recorded killing newly emerged seedlings, severely distorting leaves, scarring the surface of fruits, and vectoring major plant pathogens³. The thrips may spread long distances through the trade of plants, fruit, or cut flowers.

Worldwide Distribution: Scirtothrips dorsalis is believed to be native to South-East Asia or the Indian subcontinent⁴. It has spread across much of Asia and to parts of Australia, Papua New Guinea, and the Solomon Islands. It has also been found on several Caribbean islands as well as in Suriname, Venezuela, and Ivory Coast¹. It was detected in Hawaii in 1987, Florida in 2005, Puerto Rico in 2006, Georgia and Texas in 2007, and Louisiana in 2009.

Official Control: Scirtothrips dorsalis is considered a quarantine pest in Europe⁵ and New Zealand⁶.

California Distribution: Scirtothrips dorsalis has only been found in the environment of California in Orange and Los Angeles counties.

California Interceptions: Scirtothrips dorsalis is occasionally intercepted on plants or fresh plant parts from Florida, Texas, and Hawaii.

The risk Scirtothrips dorsalis (Chilli thrips) would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: The present distribution of Scirtothrips dorsalis corresponds to USDA plant hardiness zones 8-12, indicating that it is likely to find a favorable climate in most of California. The polyphagous nature of thrips makes it likely that the insect would encounter suitable host plants throughout the state. Chilli thrips receives a High (3) in this category.

Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

2) Known Pest Host Range: Scirtothrips dorsalis is a polyphagous thrips that is reported to feed on more than 200 plant species in 70 families³. Chilli thrips receives a High (3) in this category.

Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.
– Medium (2) has a moderate host range.
– High (3) has a wide host range.

3) Pest Dispersal Potential: Chilli thrips reproduces rapidly: each female lays 60-200 eggs and the thrips completes its life cycle in 12-22 days². The thrips is reported to disperse only 12-20m on its own¹, but it may spread long distance in commerce on plants or plant parts. Scirtothrips dorsalis receives a High (3) in this category.

Evaluate the natural and artificial dispersal potential of the pest. Score:

4) Economic Impact: Although Scirtothrips dorsalis is not reported to be a significant economic pest in Florida, there could be impacts to fresh navel orange and table grape exports from California. Citrus is a known host of the thrips, and thrips are notorious for hiding inside the navel of oranges and eluding packing house cleaning. As chilli thrips is considered to be a quarantine pest by New Zealand and Europe, the presence of this insect in California may trigger a loss of markets. Chilli thrips also feeds on a wide variety of ornamental plants, which it disfigures by causing leaf curling. This may increase production costs or lower the value of nursery stock. Chilli thrips has been reported to vector seven major plant pathogens: chilli leaf curl virus, peanut necrosis virus, melon yellow spot virus, watermelon silver mottle virus, capsicum chlorosis virus, and tomato spotted wilt virus⁴. Scirtothrips dorsalis receives a High (3) in this category.

Evaluate the economic impact of the pest to California using the criteria below. Score:

– Low (1) causes 0 or 1 of these impacts.
– Medium (2) causes 2 of these impacts.
– High (3) causes 3 or more of these impacts.

5) Environmental Impact: Munz’s onion (Allium munzii), Yosemite onion (Allium yosemitense), and small-leaved rose (Rosa minutifolia) are listed as threatened or endangered plants in California and are potential hosts of Scirtothrips dorsalis. The thrips is likely to trigger additional treatment programs by residents who find infested plants unsightly, as well as by the nursery industry. Chilli thrips receives a High (3) in this category.

Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.
B. The pest could directly affect threatened or endangered species.
C. The pest could impact threatened or endangered species by disrupting critical habitats.
D. The pest could trigger additional official or private treatment programs.
E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.
– Medium (2) causes one of the above to occur.
– High (3) causes two or more of the above to occur.

**Consequences of Introduction to California for Scirtothrips dorsalis (Chilli thrips): High (15)**

Add up the total score and include it here.

–Low = 5-8 points
–Medium = 9-12 points
–High = 13-15 points

6) Post Entry Distribution and Survey Information: Scirtothrips dorsalis has been confirmed in Orange and Los Angeles Counties and receives a Low (-1) in this category.

Final Score:

The final score is the consequences of introduction score minus the post entry distribution and survey information score: High (14)

Uncertainty:

There have not been any statewide thrips surveys in recent years; it is possible that Scirtothrips dorsalis could have a more widespread distribution in California. There are no effective detection technologies that would allow for a survey to delimit the infestation or find new infestations in other areas. Because the thrips lays eggs inside plant tissue and is polyphagous, visual surveys might not find low levels of infestation in nurseries or the environment. It is also possible that existing treatments for thrips may also limit impacts of chilli thrips.

Conclusion and Rating Justification:

The spread of Scirtothrips dorsalis through California is likely to have significant economic and environmental impacts. However, it is already known to be established in Orange and Los Angeles Counties and is not under official control. Scirtothrips dorsalis is already established in other states, has been proposed for deregulation by USDA, and is not known to be under consideration for FRSMP. A “B” rating is justified.

References:

¹Culliney, T.W. 2014. Deregulation Evaluation of Established Pests (DEEP); DEEP Report on Scirtothrips dorsalis Hood: Chilli thrips.

² Ludwig, Scott W. and C. Bográn. 2007. Chilli Thrips: A New Pest in the Home Landscape. Texas Cooperative Extension. https://insects.tamu.edu/extension/publications/epubs/eee-00041.pdf

³Kumar, Vivek, Dakshina R. Seal, Garima Kakkar, Cindy L. McKenzie, and Lance S. Osborne. 2012. New tropical fruit hosts of Scirtothrips dorsalis (Thysanoptera: Thripidae) and its relative abundance on them in south Florida. Florida Entomologist 95(1):205-207. http://www.bioone.org/doi/pdf/10.1653/024.095.0134

⁴High Priority Organism: Scirtothrips dorsalis (Chilli thrips). New Zealand Kiwifruit Vine Health Inc. http://www.kvh.org.nz/vdb/document/91534

⁵EPPO Data Sheets on Quarantine Pests: Scirtothrips dorsalis. https://www.eppo.int/QUARANTINE/insects/Scirtothrips_dorsalis/SCITDO_ds.pdf

⁶New Zealand Import Risk Analysis: Table Grapes (Vitis vinifera) from China. 2009. MAF Biosecurity New Zealand. http://www.biosecurity.govt.nz/files/regs/imports/risk/table-grapes-china-ra.pdf

Responsible Party:

Jason Leathers, 1220 N Street, Sacramento, CA, 95814, (916) 654-1211, plant.health[@]cdfa.ca.gov.

Comment Format:

♦ Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s) being commented on, as shown below.

Example Comment:

Consequences of Introduction: 1. Climate/Host Interaction: [Your comment that relates to “Climate/Host Interaction” here.]

♦ Posted comments will not be able to be viewed immediately.

♦ Comments may not be posted if they:

Contain inappropriate language which is not germane to the pest rating proposal;

Contains defamatory, false, inaccurate, abusive, obscene, pornographic, sexually oriented, threatening, racially offensive, discriminatory or illegal material;

Violates agency regulations prohibiting sexual harassment or other forms of discrimination;

Violates agency regulations prohibiting workplace violence, including threats.

♦ Comments may be edited prior to posting to ensure they are entirely germane.

♦ Posted comments shall be those which have been approved in content and posted to the website to be viewed, not just submitted.

Pest Rating: B

Posted by ls

Hemiptera, Insects, Mites & Earthworms

Acutaspis agavis (Townsend & Cockerell): Agave scale

October 21, 2015 Jason Leathers

California Pest Rating for

Acutaspis agavis (Townsend & Cockerell): Agave scale

Hemiptera: Diaspididae

Pest Rating: B

PEST RATING PROFILE

Initiating Event:

On March 21, 2014, Dr. Gillian Watson identified the armored scale Acutaspis agavis from a sample collected from plants growing outdoors at a school in La Jolla, San Diego County. A heavy infestation was reported at the site on the adaxial leaf surfaces of Agave tequilana. Tissue dieback was reported on the most infested leaves and there was no evidence of parasitism or predation. The insect is currently Q-rated, so a pest rating proposal is needed to determine future direction.

History & Status:

Background: Acutaspis agavis is host specific to Agave spp. The primary pathway for spread of the scale is likely the movement of infested agave plants.

Worldwide Distribution: Acutaspis agavis is probably native to Mexico. It has also been reported from Costa Rica, Venezuela, and Trinidad and Tobago. In the United States it has been found in Arizona, Florida, and Texas.

Official Control: Acutaspis agavis is not known to be under official control in any other states or nations.

California Distribution: Acutaspis agavis is only known from an incursion at a school in La Jolla.

California Interceptions: The only instance of an Acutaspis agavis detection in a regulatory situation was in a nursery in El Cajon in 2012.

The risk Acutaspis agavis (Agave scale) would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Agave are commonly grown as ornamental plants in California and the scale is expected to be able to establish wherever they are grown. Acutaspis agavis receives a High(3) in this category.

Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

– Low (1) Not likely to establish in California; or likely to establish in very limited areas.

– Medium (2) may be able to establish in a larger but limited part of California.

– High (3) likely to establish a widespread distribution in California.

2) Known Pest Host Range: Acutaspis agavis is specific to Agave The scale receives a Low(1) in this category.

Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.

– Medium (2) has a moderate host range.

– High (3) has a wide host range.

3) Pest Dispersal Potential: Evidence suggests that Acutaspis agavis has two generations per year²and each female is presumably capable of laying hundreds of eggs. Adult female armored scales are immobile, but populations may be transported long distances through commerce in infested plants. Acutaspis agavis receives a High(3) in this category.

Evaluate the natural and artificial dispersal potential of the pest. Score:

– Low (1) does not have high reproductive or dispersal potential.

– Medium (2) has either high reproductive or dispersal potential.

– High (3) has both high reproduction and dispersal potential.

4) Economic Impact: Acutaspis agavis has the potential to increase production costs of Agave plants in the nursery industry. The scale is not expected to lower crop yield, trigger lost markets, alter cultural practices, vector other organisms, injure animals, or interfere with water supplies. Agave scale receives a Low(1) in this category.

Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.

B. The pest could lower crop value (includes increasing crop production costs).

C. The pest could trigger the loss of markets (includes quarantines).

D. The pest could negatively change normal cultural practices.

E. The pest can vector, or is vectored, by another pestiferous organism.

F. The organism is injurious or poisonous to agriculturally important animals.

G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.

– Medium (2) causes 2 of these impacts.

– High (3) causes 3 or more of these impacts.

5) Environmental Impact: Acutaspis agavis has the potential to trigger new chemical treatments in the nursery industry and by residents who find infested plants unsightly. Agave plants are popular and widely grown, especially in southern California. In the absence of natural enemies agave scale has the potential to significantly impact these cultural practices. Agave scale is not expected to lower biodiversity, disrupt natural communities, or change ecosystem processes. The scale is also not expected to affect threatened or endangered species or disrupt critical habitats. Agave scale receives a High(3) in this category.

Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.

B. The pest could directly affect threatened or endangered species.

C. The pest could impact threatened or endangered species by disrupting critical habitats.

D. The pest could trigger additional official or private treatment programs.

E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.

– Medium (2) causes one of the above to occur.

– High (3) causes two or more of the above to occur.

**Consequences of Introduction to California for Acutaspis agavis (Agave scale): Medium(11)**

Add up the total score and include it here.

–Low = 5-8 points

–Medium = 9-12 points

–High = 13-15 points

6) Post Entry Distribution and Survey Information: Acutaspis agavis is only known from an incursion at a school in La Jolla. It is unknown if the scale has spread to other agave plants in the area. Agave scale receives a Low(-1) in this category.

–Not established (0) Pest never detected in California, or known only from incursions.

–Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).

–Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.

–High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

Final Score:

The final score is the consequences of introduction score minus the post entry distribution and survey information score: Medium(10)

Uncertainty:

Agave plants are popular landscape plants, especially in southern California. There have been no surveys for Acutaspis agavis and it may be present in other locations.

Conclusion and Rating Justification:

Economic impacts of Acutaspis agavis should be limited to possible increases in production costs of agave plants in the nursery industry. However, the entry of agave scale into California may have significant environmental impacts due to the popularity of the plant and the absence of its natural enemies. A B-rating is justified.

References:

¹Systematic Entomology Laboratory. http://www.sel.barc.usda.gov/catalogs/diaspidi/Acutaspisagavis.htm

²Salas-Araiza, M.D., R.W. Jones, G. Montesinos-Silva, E. Salazar-Solis, L.A. Parra-Negrete, O. Martinez-Jaime, R. Ramirez-Malagon, and S. Flores-Mejia. 2008. Population dynamics of the agave scale, Acutaspis agavis (Hemiptera: Diaspididae), on Agave tequilana var. azul (Agavaceae) in Central Mexico. Southwestern Entomologist 33(4):289-298. http://www.bioone.org/doi/abs/10.3958/0147-1724-33.4.289

Responsible Party:

Jason Leathers, 1220 N Street, Sacramento, CA, 95814, (916) 654-1211, plant.health[@]cdfa.ca.gov.

Pest Rating: B

Posted by ls

Coleoptera, Insects, Mites & Earthworms

Dactylotrypes longicollis (Wollaston): Beetle

October 21, 2015 Jason Leathers

California Pest Rating for

Dactylotrypes longicollis dorsal Collected off of Trithrinax brasiliensis (Image Citation: Steven Valley, Oregon Dept of Ag, Bugwood.org) — Dactylotrypes longicollis dorsal Collected off of Trithrinax brasiliensis
(Image Citation: Steven Valley, Oregon Dept of Ag, Bugwood.org)

Dactylotrypes longicollis (Wollaston): Beetle

Coleoptera: Curculionidae

Pest Rating: C

PEST RATING PROFILE

Initiating Event:

On October 13, 2015 Dr. Andrew Cline identified two beetles collected from a Lindgren funnel trap as Dactylotrypes longicollis. A pest rating proposal is required to assign a permanent pest rating.

History & Status:

Background: Dactylotrypes longicollis feeds on the seeds of palms including wooly jelly palm (Butia eriospatha), Mediterranean fan palm (Chamaerops humilis), Canary Island date palm (Phoenix canariensis), date palm (Phoenix dactylifera), Senegal date palm (Phoenix reclinata), Brazilian needle palm (Trithrinax brasiliensis), and lady palm (Rhapis excelsa)¹. The beetle may be transported long distances when infested palm seeds or plants are moved.

Worldwide Distribution: Dactylotrypes longicollis is native to the Canary Islands and Madeira¹. From there it has spread to France, Italy, mainland Spain, and the Slovak Republic¹.

Official Control: Dactylotrypes longicollis is not known to be under official control in any states or nations. Dactylotrypes spp. are listed as harmful organisms by Peru².

California Distribution: Dactylotrypes longicollis has only been found in Fullerton (Orange County), San Marino (Los Angeles County), and Carpinteria (Santa Barbara County).

California Interceptions: Dactylotrypes longicollis has not been found in any regulatory situations in California.

The risk Dactylotrypes longicollis would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: The known hosts and natural geographic range of Dactylotrypes longicollis indicate that the beetle is likely to be limited to southern California¹. It receives a Medium (2) in this category.

Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

– Low (1) Not likely to establish in California; or likely to establish in very limited areas.

– Medium (2) may be able to establish in a larger but limited part of California.

– High (3) likely to establish a widespread distribution in California.

2) Known Pest Host Range: Dactylotrypes longicollis is only known to feed on the seeds of seven species of palms. It receives a Low (1) in this category.

Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.

– Medium (2) has a moderate host range.

– High (3) has a wide host range.

3) Pest Dispersal Potential: The biology of Dactylotrypes longicollis has not been well documented. It is assumed to have a high reproductive rate and to be capable of dispersing long distances when infested palm fruit or plants are moved. It receives a High (3) in this category.

Evaluate the natural and artificial dispersal potential of the pest. Score:

– Low (1) does not have high reproductive or dispersal potential.

– Medium (2) has either high reproductive or dispersal potential.

– High (3) has both high reproduction and dispersal potential.

4) Economic Impact: The California date industry produces over 40 million pounds of dates annually and employees 2,500 people. Dactylotrypes longicollis is not known to be established in major date producing nations and it is uncertain if the industry will be affected. It is possible that the beetle could reduce crop yield or increase crop production costs. The beetle is not expected to disrupt markets, change cultural practices, vector other organisms, injure animals, or disrupt water supplies. It receives a Medium (2) in this category.

Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.

B. The pest could lower crop value (includes increasing crop production costs).

C. The pest could trigger the loss of markets (includes quarantines).

D. The pest could negatively change normal cultural practices.

E. The pest can vector, or is vectored, by another pestiferous organism.

F. The organism is injurious or poisonous to agriculturally important animals.

G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.

– Medium (2) causes 2 of these impacts.

– High (3) causes 3 or more of these impacts.

5) Environmental Impact: In California Dactylotrypes longicollis is not expected to lower biodiversity, disrupt natural communities, or change ecosystem processes. It is not likely to affect threatened or endangered species or disrupt critical habitats. It could trigger new treatment programs in the date industry. It is not expected to impact cultural practices, home/urban gardening, or ornamental plantings. Dactylotrypes longicollis receives a Medium (2) in this category.

Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.

B. The pest could directly affect threatened or endangered species.

C. The pest could impact threatened or endangered species by disrupting critical habitats.

D. The pest could trigger additional official or private treatment programs.

E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.

– Medium (2) causes one of the above to occur.

– High (3) causes two or more of the above to occur.

**Consequences of Introduction to California for Dactylotrypes longicollis: Medium (10)**

Add up the total score and include it here.

–Low = 5-8 points

–Medium = 9-12 points

–High = 13-15 points

6) Post Entry Distribution and Survey Information: Dactylotrypes longicollis is known to be established in Orange, Los Angeles, and Santa Barbara counties. It receives a Medium (-2) in this category.

–Not established (0) Pest never detected in California, or known only from incursions.

–Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).

–Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.

–High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

Final Score:

The final score is the consequences of introduction score minus the post entry distribution and survey information score: Low (8)

Uncertainty:

We do not know how effective the Lindgren funnel is at detecting Dactylotrypes longicollis. It is quite possible that the beetle is much more widespread in California.

Conclusion and Rating Justification:

Dactylotrypes longicollis has been established across much of southern California since before 2009. No economic or environmental impacts have been attributed to the beetle. A “C” rating is justified.

References:

¹ LaBonte, James R. and Curtis Y. Takahashi. 2012. Dactylotrypes longicollis (Wollaston) (Coleoptera: Curculionidae: Scolytinae): an exotic bark beetle new to California and North America. Pan-Pacific Entomologist. 88(2): 222-230 http://www.bioone.org/doi/abs/10.3956/2012-18.1

² USDA Phytosanitary Certificate Issuance & Tracking System (PCIT) Phytosanitary Export Database (PExD). https://pcit.aphis.usda.gov/pcit/

Responsible Party:

Jason Leathers, 1220 N Street, Sacramento, CA, 95814, (916) 654-1211, plant.health[@]cdfa.ca.gov.

Pest Rating: C

Posted by ls

Hymenoptera, Insects, Mites & Earthworms

Formica francoeuri Bolton: Native Ant

October 9, 2015 Jason Leathers

California Pest Rating for

Formica francoeuri Bolton: Native Ant

Hymenoptera: Formicidae

Pest Rating: C

PEST RATING PROFILE

Initiating Event:

On September 25, 2015 it was found that a resident of Orange County is selling queen ant starter colonies for Formica francoeuri. An internet search reveals that this ant is commonly kept by hobbyists. A pest rating proposal is required to determine future direction on this pest.

History & Status:

Background: Formica francoeuri nests in soil and forages for honeydew from aphids and mealybugs¹. It is known to tend the larvae of at least six species of lycaenid butterflies in California². It is not known to have been inadvertently spread via any human assisted pathways.

Worldwide Distribution: Formica francoeuri is native to California and Baja California³. It is not known to have invaded any other states or nations.

Official Control: Formica francoeuri is not known to be under official control in any other states or nations. However, all ants are considered harmful organisms by Australia and Nauru⁴.

California Distribution: Formica francoeuri is native to and widespread in California.

California Interceptions: Formica francoeuri has not been reported in any regulatory situations in California.

The risk Formica francoeuri would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Formica francoeuri is native to and widespread in California and is not likely to establish in parts of the state where it does not already occur. It receives a Low (1) in this category.

Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

– Low (1) Not likely to establish in California; or likely to establish in very limited areas.

– Medium (2) may be able to establish in a larger but limited part of California.

– High (3) likely to establish a widespread distribution in California.

2) Known Pest Host Range: Formica francoeuri is a generalist feeder on honeydew and has never been documented as a plant pest. It receives a Low (1) in this category.

Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.

– Medium (2) has a moderate host range.

– High (3) has a wide host range.

3) Pest Dispersal Potential: Ants typically have high reproductive rates. Formica francoeuri has not been reported to move long distances in commerce. It receives a Medium (2) in this category.

Evaluate the natural and artificial dispersal potential of the pest. Score:

– Low (1) does not have high reproductive or dispersal potential.

– Medium (2) has either high reproductive or dispersal potential.

– High (3) has both high reproduction and dispersal potential.

4) Economic Impact: Formica francoeuri is already widespread in California and it has not lowered any crop yields or reduced crop values. Its presence has not disrupted any markets. It has not changed cultural practices or vectored other organisms. It is not known to have injured any animals or interfered with any water supplies. Formica francoeuri receives a Low (1) in this category.

Evaluate the economic impact of the pest to California using the criteria below. Score:

A. The pest could lower crop yield.

B. The pest could lower crop value (includes increasing crop production costs).

C. The pest could trigger the loss of markets (includes quarantines).

D. The pest could negatively change normal cultural practices.

E. The pest can vector, or is vectored, by another pestiferous organism.

F. The organism is injurious or poisonous to agriculturally important animals.

G. The organism can interfere with the delivery or supply of water for agricultural uses.

– Low (1) causes 0 or 1 of these impacts.

– Medium (2) causes 2 of these impacts.

– High (3) causes 3 or more of these impacts.

5) Environmental Impact: Formica francoeuri is native to and widespread in California and it has not been found to lower biodiversity, disrupt natural communities, or change ecosystem processes. It has not affected any threatened or endangered species or disrupted critical habitats. The ant is not known to have triggered any treatment programs or impacted cultural practices, home/urban gardening, or ornamental plantings. Formica francoeuri receives a Low (1) in this category.

Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.

B. The pest could directly affect threatened or endangered species.

C. The pest could impact threatened or endangered species by disrupting critical habitats.

D. The pest could trigger additional official or private treatment programs.

E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.

– Medium (2) causes one of the above to occur.

– High (3) causes two or more of the above to occur.

**Consequences of Introduction to California for Formica francoeuri (native ant): Low (6).**

Add up the total score and include it here.

–Low = 5-8 points

–Medium = 9-12 points

–High = 13-15 points

6) Post Entry Distribution and Survey Information: Formica francoeuri is widespread in California and receives a High (-3) in this category.

–Not established (0) Pest never detected in California, or known only from incursions.

–Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).

–Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.

–High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

Final Score:

The final score is the consequences of introduction score minus the post entry distribution and survey information score: Low (3)

Uncertainty:

There is low uncertainty with this ant.

Conclusion and Rating Justification:

Formica francoeuri is a native ant that is widespread in California and is not known to have ever had any negative economic or environmental impacts. No significant impacts are expected from hobbyists trading colonies of this ant within the state. A “C” rating is justified.

References:

¹ Robinson, William H. 2005. Urban Insects and Arachnids: A Handbook of Urban Entomology. Cambridge University Press. https://books.google.com/books?id=aluUgDVYJ8wC&pg=PA247&lpg=PA247&dq=formica+francoeuri&source=bl&ots=HusuoBZINl&sig=UtduAv7yswlPy49d0H852RenfSQ&hl=en&sa=X&ved=0CCIQ6AEwATgUahUKEwjrzf_mm6LIAhWLTIgKHc-YCv0#v=onepage&q=formica%20francoeuri&f=false

² Oliver, Jeffrey C. and Laura R. Stein. 2011. Evolution of influence: signaling in a lycaenid-ant interaction. Evol. Ecol. 25: 1205-1216. http://www.researchgate.net/profile/Laura_Stein2/publication/251313007_Evolution_of_influence_signaling_in_a_lycaenid-ant_interaction/links/53ee51f00cf26b9b7dc793ba.pdf

³ Formica francoeuri. From AntWiki: http://www.antwiki.org/wiki/Formica_francoeuri

⁴ USDA Phytosanitary Certificate Issuance & Tracking System (PCIT) Phytosanitary Export Database (PExD). https://pcit.aphis.usda.gov/pcit/

Responsible Party:

Jason Leathers, 1220 N Street, Sacramento, CA, 95814, (916) 654-1211, plant.health[@]cdfa.ca.gov.

PEST RATING: C

Posted by ls

Hemiptera, Insects, Mites & Earthworms

Hemiberlesia ithacae (Ferris): Hemlock Scale – Synonym: Abgrallaspis ithacae

September 21, 2015 Jason Leathers

California Pest Rating for

Hemiberlesia ithacae (Ferris): Hemlock Scale

Synonym: Abgrallaspis ithacae

Hemiptera: Diaspididae

Pest Rating: B

PEST RATING PROFILE

Initiating Event:

On December 11, 2013 an official with Santa Cruz County contacted CDFA with questions regarding the risk associated with Abgrallaspis ithacae (Hemlock Scale). The current destruction of large numbers of Christmas wreaths due to the presence of the scale is considered punitive by some merchants. The insect is currently Q-rated, so a pest rating proposal is needed to determine future direction.

History & Status:

Background:

Hemlock scale feeds on the undersides of the needles of several species of trees. The scale is only known to feed on Canada balsam fir (Abies canadensis), grand fir (Abies grandis), Colorado blue spruce (Picea pungens), douglas fir (Pseudotsuga taxifolia), eastern hemlock (Tsuga canadensis), and western hemlock (Tsuga heterophylla). Hemlock scale has two generations per year and overwinters as second-instars.

Worldwide Distribution: Hemlock scale is native to North America. It is confirmed to be in Indiana, Maryland, New York, and Virginia². It is also reported from Connecticut, Georgia, Ohio, Pennsylvania, Tennessee, and West Virginia². There are also published records from Idaho, Montana, Washington, and Oregon; however, these records are reported to be incorrect².

Official Control: Hemlock scale is not known to be under official control in any states or nations.

California Distribution: Hemlock scale has never been found in the environment of California.

California Interceptions: Hemlock scale is often intercepted on shipments of Christmas wreaths, trees, and plants.

The risk hemlock scale (Abgrallaspis ithacae) would pose to California is evaluated below.

Consequences of Introduction:

1) Climate/Host Interaction: Hosts of hemlock scale are restricted to the cooler parts of California but may also be grown elsewhere as ornamentals. The scale receives a Medium(2) in this category.

Evaluate if the pest would have suitable hosts and climate to establish in California. Score:

2) Known Pest Host Range: Hemlock scale feeds on trees in four genera in one plant family. The scale receives a Low(1) in this category.

Evaluate the host range of the pest. Score:

– Low (1) has a very limited host range.
– Medium (2) has a moderate host range.
– High (3) has a wide host range.

3) Pest Dispersal Potential: Armored scales can reproduce rapidly and may be transported long distances through the trade of nursery stock. However, females have limited mobility so the trade in plant parts that are not for planting is not high risk for introducing the scale. It is likely that infested Christmas trees and wreaths will be disposed of as green waste, some of which may end up as mulch. However, the limited host range of this scale reduces the likelihood that the mulch will end up in close proximity to living host plants. Furthermore, hemlock scale overwinters as second instars. It is likely that cut trees and wreaths shipped in late fall and early winter will dry out before spring, reducing their viability as host material and eliminating the possibility of overwintering second instars completing development. Hemlock scale receives a Medium(2) in this category.

Evaluate the natural and artificial dispersal potential of the pest. Score:

4) Economic Impact: Heavy infestations of hemlock scale are reported to cause early leaf drop, dieback of branches, and defoliation of trees². This reduces vigor and severe infestations result in death of trees³. This has the potential to lower yield and crop value and increase production costs at Christmas tree farms and some forests. Hemlock scale receives a Medium(2) in this category.

Evaluate the economic impact of the pest to California using the criteria below. Score:

– Low (1) causes 0 or 1 of these impacts.
– Medium (2) causes 2 of these impacts.
– High (3) causes 3 or more of these impacts.

5) Environmental Impact: Hemlock scale is not expected to lower biodiversity, disrupt natural communities, or change ecosystem processes. The scale is not known to feed on any plants in genera that contain threatened or endangered species in California. Hemlock scale is not expected to disrupt critical habitats. The scale could trigger some additional official or private treatment programs in Christmas tree farms or forests^2,3. The scale is not expected to significantly impact cultural practices, home/urban gardening, or ornamental plantings. Hemlock scale receives a Medium(2) in this category.

Evaluate the environmental impact of the pest on California using the criteria below.

A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.
B. The pest could directly affect threatened or endangered species.
C. The pest could impact threatened or endangered species by disrupting critical habitats.
D. The pest could trigger additional official or private treatment programs.
E. The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

– Low (1) causes none of the above to occur.
– Medium (2) causes one of the above to occur.
– High (3) causes two or more of the above to occur.

Consequences of Introduction to California for Hemlock Scale (Abgrallaspis ithacae): Medium(9)

Add up the total score and include it here.

–Low = 5-8 points
–Medium = 9-12 points
–High = 13-15 points

6) Post Entry Distribution and Survey Information: Hemlock scale has not been found in the environment of California. It receives a Not established(0) in this category.

-Not established (0) Pest never detected in California, or known only from incursions.

Final Score:

7) The final score is the consequences of introduction score minus the post entry distribution and survey information score: Medium(9)

Uncertainty:

It is possible that hemlock scale could jump to new hosts in California. It is also possible that hemlock scale may be managed by existing IPM programs in Christmas tree farms.

Conclusion and Rating Justification:

Hemlock scale may have limited economic impacts to Christmas tree farms and forests. The environmental impacts of the scale are expected to be limited to possible chemical treatments of the scale in Christmas tree farms and managed forests. A “B”-rating is justified.