Invasive Insect Species Refresher
•
5 likes•1,395 views
Green Industry Continuing Education Series November 18, 2015 12 noon - 2 p.m. Instructors: Darren Blackford, Entomologist, USDA-Forest Service Gene Phillips, Forest Health Specialist, Nevada Division of Forestry
Recommended
More Related Content
What's hot
What's hot (20)
Similar to Invasive Insect Species Refresher
Similar to Invasive Insect Species Refresher (20)
More from University of Nevada Cooperative Extension
More from University of Nevada Cooperative Extension (20)
Recently uploaded
Recently uploaded (20)
Invasive Insect Species Refresher
- 1. Invasive Insect Species-Refresher What You Need to Know Darren Blackford Gene Phillips Entomologist Forest Health Specialist USDA-Forest Service Nevada Division of Forestry
- 2. What Are Invasive Species? An organism that is not native to the local environment and is capable of harming the economy, environment, or human health The term invasive is reserved for the most aggressive and destructive non- native species Early detection and action is important!
- 3. Invasive Insect Pests • Emerald Ash Borer (Agrilus planipennis) • European/Asian Gypsy Moth ( Lymantria dispar/asiatica) • Walnut Twig Beetle (Pityophthorus juglandis) • Asian Longhorned Beetle (Anoplophora glabripennis) • Banded Elm Bark Beetle (Scolytus schevyrewi) • Sirex Woodwasp (Sirex noctilio)
- 4. Emerald Ash Borer (Agrilus planipennis) A Threat to Nevada’s Ash Trees
- 5. Emerald ash borer Profile Scientific name: Agrilus planipennis Common name: Emerald ash borer (EAB) Native to: Eastern Russia, Northern China, Japan, and Korea Date of U.S. introduction: 2002 (McCullough and Usborne 2011) Means of introduction: Arrived accidentally in cargo imported from Asia (McCullough and Usborne 2011) Impact: Trees lose 30 to 50% of canopy after 2 years infestation and die within 3–4 years
- 7. Emerald Ash Borer in North America First detected in 2002 in Michigan and Ontario Arrived via infested wood packing material Currently found in more than 20 mid-western and eastern states, killing tens of millions of ash trees In September 2013, EAB was found in Boulder, Colorado Evidence suggests that EAB is generally established in an area for several years before it is detected
- 11. How Does Emerald Ash Borer Spread? Normal flight is between one-half to two miles per year Firewood has been a major means of transporting EAB
- 13. Identification of Emerald Ash Borer Adults Bright, metallic, green-colored beetle with a bronze head and a flattened body Abdominal segments underneath wing covers are purple iridescent Approximately 1/2 inch long and 1/8 inch wide Males and females are similar in appearance Very detailed guide: www.emeraldashborer.info under “About EAB”
- 14. Agrilus spp. have a very distinctive shape that separates them from most of the other genera of Buprestidae
- 15. All Agrilus spp. exhibit some degree of natural variation in size and coloration
- 17. Emerald Ash Borer eggs are small (1/16”)and nearly impossible to locate on bark or in bark crevices
- 18. Identification of Emerald Ash Borer Larvae Larvae are cream-colored and tapeworm-like Have 10 abdominal segments, a flattened abdomen, and a pair of pincer-like appendages on the last segment Reach ~ 1 inch in length when fully grown
- 19. Identification of Emerald Ash Borer Pupae Pupae are initially creamy white, but their body begins to darken as they develop
- 20. All ash trees (Fraxinus spp.) are susceptible, and both healthy and unhealthy trees can be attacked Mountain ash (Sorbus) is not a true ash species EAB infestations have spread to the white fringe tree (Chionanthus virginicus) The larvae are the damaging life-stage (the adults not so much) The larvae feeds and tunnels through the vascular system of the tree (cambium layer), cutting off the water and nutrient supply to the tree Small trees die within 1-2 years of becoming infested; large trees are killed in 3-4 years See USU’s Factsheet on Emerald Ash Borer for information on ash identification
- 21. EAB-Life Cycle • 1-2 year (health) • Adults-3 weeks • 30-60 eggs (200) 7-10 days
- 22. Signs and Symptoms of Emerald Ash Borer Adult feeding
- 23. Signs and Symptoms of Emerald Ash Borer D-shaped exit holes
- 24. Signs and Symptoms of Emerald Ash Borer Serpentine galleries
- 25. Signs and Symptoms of Emerald Ash Borer Epicormic growth / Sucker shoots
- 26. Signs and Symptoms of Emerald Ash Borer Woodpecker damage
- 27. Signs and Symptoms of Emerald Ash Borer Canopy dieback
- 28. Signs and Symptoms of Emerald Ash Borer Canopy dieback
- 29. Signs and Symptoms of Emerald Ash Borer Canopy dieback
- 30. Signs and Symptoms of Emerald Ash Borer Canopy dieback
- 31. Other Wood Borers of Ash Lilac-ash borer (Podosesia syringae)
- 32. What is Being Done? Monitoring Visual surveys Girdled trees (EAB is attracted to stressed trees) Purple panel traps (GLV, manuka oil) Branch sampling using draw-knives
- 35. What is Being Done? Prevention and Management Regulation of infested areas – restrict movement of ash, including firewood, lumber, and logs Removing ash from planting lists; Improve tree conditions Girdled trees – removing population sinks Biological Control Parasitic wasps Pathogenic fungi Woodpeckers Beetles
- 36. What is Being Done? Chemical Control (http://www.emeraldashborer.info/files/multistate_eab_insecticide_fact_sheet.pdf)
- 37. Resources Resources www.eabcolorado.com www.emeraldashborer.info http://www.emeraldashborer.info/files/ multistate_eab_insecticide_fact_sheet. pdf http://utahpests.usu.edu/caps/files/upl oads/EAB_Factsheet.compressed.pdf
- 38. Questions?
- 39. Gypsy Moth (Asian/European) AGM (Lymantria dispar asiatica) EGM (Lymantria dispar dispar)
- 40. COMPARING GYPSY MOTH •European Gypsy Moth (EGM) was intentionally introduced in the U.S. in 1869 and is now established in northeastern U.S. and southeastern Canada. •AGM like EGM prefers forest habitats and both cause defoliation and deterioration of trees and shrubs. •Host Range: AGM greater range of hosts •AGM adult females are active fliers where EGM adult females are flightless. Greater ability to disperse. Asian Gypsy Moth on left and European Gypsy Moth on right. Photo USDA-APHIS-PPQ, www.ipmimages.org
- 41. • AGM: 500 species of trees and shrubs, including many conifers and hardwoods, although Quercus is a preferred host. Other common hosts include Alnus, Betula, Corylus, Diospyros, Larix, Malus, Populus, Salix and Tilia • EGM: ~ 250 species of trees but prefer Oaks • EGM defoliate ~ 700K acres/year, millions of dollars in damage. 75 mil acres since ‘70 • In the US, over 311 million acres of susceptible forests exist for the North American strain of gypsy moth, susceptible forest acreage is far greater for AGM • Heavy or repeated defoliation causes tree mortality and increases susceptibility to other insect and disease agents • In recreation sites and urban areas dead trees are a safety hazard and affect property values in urban sites AGM/EGM Impact
- 42. • During outbreaks, frass droppings cover large areas affecting outdoor activities such as camping, barbecues, swimming and picnics. Reduced attendance in recreational areas and/or resorts may occur during outbreaks periods • Reforestation may be with non-native invasive species and can create a loss of biodiversity • Wildlife impacts due to loss of overstory or increased understory growth can be positive or negative depending on the species. • Defoliation can increase water yield and lower water quality. • Costs associated with eradication/suppression programs. In 2016 costs associated with the AGM eradication program in the Pacific NW are estimated to approach 5 million. EGM slow the spread/suppression about AGM/EGM Impact
- 44. Asian Gypsy Moth • China • South Korea • Russia • Japan
- 45. VARIATION IN LARVAL COLORATION • Evidence for adaptation to shorter egg chilling times suggesting that gypsy moth should be able to adapt to climates with warmer and shorter winters • Flight capability of females also varies widely from less than 0.5 mi up to 12- 25 mi • Outbreak periodicity varies between locations: Siberia 6-10 years, Russian Far East – 6-8 years and China 6-10 years compared to the European strain of gypsy moth where outbreak intervals vary from 6 to 36 years AGM Characteristics
- 46. Four Stages: Egg → Larva (caterpillar) → Pupae (cocoon) → and Moth AGM/EGM • Univoltine • Egg masses are the overwintering stage and may be found on trees, stones, walls, logs and other outdoor objects, 1.5 in. long and 0.75 in. wide. Egg mass contains 100-1500 eggs. The mass is covered with a buff or yellowish color which comes from the abdomen hair of the female. Eggs hatch in the spring. Larvae range from 2-3 mm to 2.5 in. long when mature. Larvae feed for 6-8 weeks. Photo credits: Ferenc Lakatos, University of West-Hungary John H. Gent, USDA Forest Service, AGM/EGM Life Cycle
- 47. Larvae stop feeding when they enter the pupal or cocoon stage. This begins in late June or July. Adults emerge in 10 to 14 days. Adults do not feed, only mate and lay eggs (1-3 weeks). Egg oviposition occurs between July and September. The eggs remain dormant during the winter and hatch in the following spring. AGM/EGM Life Cycle Larvae/Adults
- 48. Asian Gypsy Moth Egg Oviposition Preferred Sites Varies by Country
- 49. AGM/EGM Management EGM Eradication,/Suppression/BioControl/Silviculture/ Biological pesticides (Bt), trapping, mating disruption, gypsy moth nucleopolyhedrosis virus (NPV) AGM Monitoring native ports and U.S. Ports Certified “pest-free” Trapping surveys at port areas Bacillus thuringiensis-disrupts digenstive system Dimilin-inhibits growth/development Mating disruption-pheromones emitted by females to attract males. Released at high levels around infested areas, overwhelming pheromone signal emitted by the female AGM, making it difficult for male moths to locate the females and mate.
- 50. QUESTIONS ?
- 51. JUGLANDIS)/ THOUSAND CANKERS DISEASE (GEOSMITHIA MORBIDA) AN INSECT-PLANT PATHOGEN INTERACTION
- 52. WTB/TCD An Insect-Plant Pathogen Interaction Hosts (West): Black walnut (Juglans nigra), Arizona walnut (J. major), California Walnut (J. californica),
- 53. WTB/TCD WTB Distribution In green are states and the California county of Los Angeles with records of the species prior to 1960 States in orange have reported the insect since 1988. The recent (2010- 2011) records from states east of the Mississippi are presently known only from limited areas: Tennessee/Knox County and surrounding areas; Virginia/Richmond; and Pennsylvania/Bucks County.
- 54. WTB/TCD Distribution • The Walnut twig beetle was first detected in Eastern US in 2010 and has now been found in Tennessee, Virginia, Pennsylvania, North Carolina, Ohio, and Maryland. • It is widespread across Western US. While not yet in New York, WTB has been confirmed in adjacent states and poses a threat to walnuts in NY, the Northeast and New England.
- 55. WTB/TCD Impact WTB vectors TCD. The disease was observed in the 1990s but not recognized until 2008, it has killed many walnut trees planted outside their native range across the western US. It is now a serious threat to walnuts in their native eastern range. Black walnut has high economic value for wood production, throughout the native range the net volume of black walnut growing stock on timber land was valued at over $500 billion. Nut production
- 56. WTB/TCD Identification-Adults Adults: 1-5-1.9 mm, yellowish-brown bark beetle.
- 57. WALNUT TWIG BEETLE (PITYOPHTHORUS JUGLANDIS)
- 58. WTB/TCD Life Cycle 2-3 generations/year Overwinterng as adult or larvae Adults active late March-April Egg galleries created against grain Larvae feed 4-6 weeks perpendicular to egg gallery Pupation occurs Adults emerge to produce 2nd generation early summer (mid-July/late-August) Attack same or nearby tree, doesn’t have to be stressed
- 59. WTB/TCD Signs/Symptoms Galleries Nuptial Chamber Egg galleries/Larval Galleries
- 63. WTB AND TCD
- 64. BRANCH FLAGGING AND DIEBACK
- 67. TREE MORTALITY
- 68. WTB/TCD Management No effective control for TCD yet. Insecticide injection trials for WTB Bole sprays limited because of extended period of when beetles are active and coverage limited on trees Sanitation practices for TCD and WTB Chipping infested trees Pheromone trapping
- 70. Sept. 2-3, 2015 Harvesting nuts And phloem Megan Siefker
- 71. QUESTIONS?
- 72. Asian Longhorned Beetle (Anoplophora glabripennis)
- 73. Asian Longhorned Beetle Range ALB is a native of China, Korea and Taiwan ALB entered the USA at shipping ports in wooden pallets and crates infested with ALB. First discovered in 1996 in Brooklyn, NY and in 1998 in Chicago, IL.
- 74. Asian Longhorned Beetle Damage ALB larvae tunnel through tree stems and branches. Repeated damage can lead to dieback of the tree crown and eventual death of the tree.
- 75. Asian Longhorned Beetle Impact Kill trees of more than 15 plant families Negatively affects forest product industries ($178 million) maple syrup production ($67 million) tourism and recreation ($143 billion) urban, rural, and natural ecosystems ($948 million) Host tree sales ($56 million) 1997-2008: ALB eradication program ~$373 million
- 76. Asian Longhorned Beetle Hosts Maple Horsechestnut Willow Elm Birch Poplar Mimosa Hackberry Ash London plane Mountain ash
- 77. Asian Longhorned Beetle Risk Map
- 78. Asian Longhorned Beetle Activity areas
- 79. Asian Longhorned Beetle Identification-Adults Adults: Large (0.75”-1.5”). Females typically larger but great variation. Antennae white/black banding, 11-segmented. Female antennae shorter than male. Pronotum 2 large spines Elytra shiny black with white or yellowish tan spots (no bumps) Tarsi faint iridescent blue Females Males
- 80. Asian Longhorned Beetle Identification-Adults Often confused with native whitespotted pine sawyer (Monochamus scutellatus) Distinct white dot between elytra Mottled grey coloration Attacks pines
- 82. Asian Longhorned Beetle Identification-Eggs A: bolt with bark removed showing eggs. Eggs are inserted beneath the bark B: An oviposition pit on A. saccharum. These pits can be found on branches and sometimes the main bole of infested trees. Fresh oviposition pits are red or light brown and may ooze sap. C: Older oviposition pits on Acer rubrum. After a few months, oviposition pits darken.
- 85. Asian Longhorned Beetle Identification-Larvae A: An older larva. Notice the shape of the plate on the pronotum. B: Galleries created by larvae in Acer rubrum. Older instars are able to tunnel into the heartwood.
- 86. Asian Longhorned Beetle Identification-Pupae A: Pupa in pupal chamber. Frass has been packed into the entrance tunnel with a partially prechewed exit tunnel from the chamber. B: Various ages of pupae. Older pupae on the left have more sclerotized body parts compared with younger pupae on the right.
- 87. Asian Longhorned Beetle Biology One generation/year (12-18 months) Eggs laid (35-90) summer/early fall (59- 86 deg. F)(most vulnerable). Hatch in ~15 days Larvae: Early feed between xylem and phloem, late fee on xylem). Five instars Pupae: Pupal eclosion can take 12-50 days Adults: Take ~ 2 weeks to emerge. (June/July). Feed on leaf petioles and debark small branches 2-3 days then mate. 15d
- 88. Asian Longhorned Beetle Signs/Symptoms Maturation Feeding
- 93. Asian Longhorned Beetle Management Mechanical Control Cultural Control Host Plant Resistance -poplar cultivars Biocontrol agents-parasitoids/predators too broad host range. Trunk/Soil insecticide injections (Imidacloprid) Entomopathogenic fungi promising Surveys-reduce spread
- 94. QUESTIONS?
- 95. BANDED ELM BARK BEETLE (SCOLYTUS SCHEVYREWI)
- 96. Banded Elm Bark Beetle Impact • Kills weakened or stressed trees (drought) • Vectors dutch elm disease (Ophiostoma novo-ulmi)(Jocobi et al., 2013). • 2003: City of Fort Collins-Removed 27 elm trees;24 were confirmed to have DED;3 appeared to have died exclusively by attack by BEBB
- 97. Banded Elm Bark Beetle Native distribution/Hosts • Native Distribution: N. China, C. Asia, Korea, and Russia • Hosts: various elms, Russian olive, willows, woody plants in the pea family, and possibly fruit- producing trees in the rose family
- 98. Banded Elm Bark Beetle North American distribution/Hosts • First detected 2002 Aurora, CO, Ogden, UT (USDA-FS/USDA-AHIS, Rapid Detection/Early Response Pilot Proj.) • Museum specimens 1994, Denver, CO, 1998, Clovis NM, 2000, City of Industry, CA • Hosts: Elm: American, Ulmus americana, Siberian, U. pumila, English, U. thomasii, and rock elm, U. procera. 5/14/2013
- 99. Banded Elm Bark Beetle Identification • Adults: 3-4mm, brown, band across elytra • Larvae: Creamy white legless grubs in phloem and outer bark • Galleries asymmetric with overlapping larval mines Adult Egg/Larval Galleries Pupae Larvae
- 100. NATIVE AND INTRODUCED BARK BEETLES OF ELM Native elm bark beetle (NEBB), Hylurgopinus rufipes • Canada,South through Lake States to Alabama and Miss., Kansas, Neb. • Various native elms Smaller European elm bark beetle (SEEBB), Scolytus multistriatus • Throughout U.S. • Native elms, English, Jap., and Siberian elms (here, not Europe) Banded elm bark beetle (BEBB), S. schevyrewi • Western States, spreading into states east of Miss. R. • Native elms, English, Jap., and Siberian elms 2.2-2.5 mm 1.9-3.1mm 3-4 mm
- 102. Native/Introduced Bark Beetles of Elm Galleries NEBB SEEBB (galleries symmetric, fan-shaped without overlapping larval mines BEBB) BEBB • 2-3.5” long • ~60 eggs (23-123)
- 103. Native/Introduced Bark Beetles of Elm Biology Native elm bark beetle (NEBB), Hylurgopinus rufipes • Egg, Larva, Pupa, Adult • 1-2 yr life cycle dep. on lat. Smaller European elm bark beetle (SEEBB), Scolytus multistriatus • Egg, Larva, Pupa, Adult • 2 gen/year, may have 3 in south • Fly in spring and infest elms • Larvae through summer/overwinter Banded elm bark beetle (BEBB), S. schevyrewi • Egg, Larva, Pupa, Adult • 2 gen/year, may have 3 in south (45day) • Fly in spring and infest elms • Larvae through summer/overwinter 2.2-2.5 mm 1.9-3.1mm 3-4 mm
- 104. BEBB Signs/Symptoms • Branch Flagging • Exit holes in bole • Brown streaking (DED)
- 105. BEBB/DED Management • PREVENTION • Monitoring • Watering • Root-to-root transmission of DED- root graphs between trees within 50 ft of each other can be severed.
- 106. BEBB/DED Management • PREVENTION • Monitoring • Watering • Root-to-root severing • SUPRESSION • Infested trees removed, debarked, chipped, burned • Bole severing • Insecticide application to foliage before beetle flight • Azadirachtin, bifenthrin, carbaryl, cypermethrin, permethrin, etc. Exit holes in bole • Tree injections-fungicides • Pruning (10 ft. below observed streaking in flagged branch)
- 107. BEBB/DED Management • PREVENTION • Monitoring • Watering • Root-to-root severing • SUPRESSION • Infested trees removed, debarked, chipped, burned • Insecticide application to foliage before beetle flight • Azadirachtin, bifenthrin, carbaryl, cypermethrin, permethrin, etc. Exit holes in bole • Tree injections-fungicides • Pruning (10 ft. below observed streaking in flagged branch) • RESTORATION • Plant resistant variety of A. elm (Independence, Valley Forge, New Harmony, etc.)
- 108. SIREX WOODWASP (SIREX NOCTILLIO)
- 109. Sirex Woodwasp Profile Scientific name: Sirex noctilio Common name: Sirex woodwasp, European woodwasp, Eurasian woodwasp Native to: Eurasia Date of U.S. introduction: First identified in New York in 2004 Means of introduction: Accidentally introduced through imported wood products Impact: Feeds on healthy pine trees and serves as a vector for a fungus that kills pine trees
- 110. Sirex Woodwasp Hosts Known Hosts: primarily pines, but on occasion Abies (fir) and Picea (spruce). Native range hosts: (Europe, Asia, and northern Africa), Scotch (Pinus sylvestris) Austrian (P. nigra), Maritime (P. pinaster) pines Introduced range hosts: (U.S., Australia, New Zealand, South America, and South Africa), Monterey (P.radiata) loblolly (P.taeda) slash (P. elliottii) shortleaf (P.echinata) ponderosa (P. ponderosa) lodgepole (P.contorta) jack (P. banksiana)
- 111. Sirex Woodwasp Impact Has killed upwards of 80% of pine plantations During oviposition, the female wasp lays eggs with or without a mucoid substance and a symbiotic fungus for the larvae to feed on once they hatch. The mucoid substance is toxic to trees and aids in tree decline. The ascospores from the symbiotic fungus, Amylostereum areolatum, are also pathogenic.
- 112. Sirex Woodwasp Profile Invasive species in many parts of the world, including Australia, New Zealand, North America, South America, and South Africa.
- 113. Sirex Woodwasp U.S.Range (2011) U.S. Range
- 115. Sirex Woodwasp Habitat Native habitat Introduced Predicted future habitat
- 116. Sirex Woodwasp Identification-Adults Male: orange mid-section of abdomen, black hind legs, front 2 pairs of legs are orange. (0.35-1.26”) Female: solid iron blue body, orange legs (all 3 pairs). (0.59–1.42 in. Ovipositor below tapering tip of abdomen Both: Pointed abdomen, long black bristle-shaped antennae MaleFemale
- 117. Sirex Woodwasp Identification-Eggs/Larvae Eggs: Eggs: sausage shaped, creamy white, ~ 0.057” long (1.46 mm) and ~ 0.01” wide (0.3 mm) Larvae: cylindrical, legless, creamy white grubs, up to 1.18” long (30 mm), with a distinctive dark “spike” (or spine) at the rear of the abdomen
- 118. Sirex Woodwasp Identification-Pupae Pupa in chamber and frass packed larval tunnels.
- 119. Sirex Woodwasp Life Cycle 1 Generations/year (/2 yrs in cooler climates) Complex interaction between several organisms Adult deposits fungus (Amylostereum areolatum) from mycangia and toxic mucus. Mucus disables water and nutrient transport, causing wilting and ideal conditions for fungus Fungus spreads and invades vascular system of tree, dries out wood and breaks down cellulose. June-Sept (212) 6 stages
- 120. Sirex Woodwasp Signs/Symptoms SWW are most likely to infest weak, injured, diseased, very rapidly growing, or otherwise stressed living host trees, and dead or fallen host trees. Foliage wilts, needles point straight down and turn light green/yellow to red/brown over several months.
- 121. Sirex Woodwasp Signs/Symptoms Resin beads or dribbles on the bark from oviposition drilling wounds. Round exit holes ⅛-⅜” (3-8 mm) in diameter created by adults emerging in year two.
- 122. Sirex Woodwasp Management Mechanical/Physical Control: chipping infested wood Biocontrol agents Beddingia siricidicola -parasitic nematode-has shown to infect up to 70% of the wasps. Infects larvae, sterilizes adult females (where there is larvae) The nematodes feed on the symbiotic fungus and use SWW as a means of dispersal (where there is no larvae) The introductions of parasitic wasps. Megarhyssa nortoni nortoni, Rhyssa persuasoria persuasoria and Ibalia leucospoides leucospoides have been successful at hyperparasitism, but do not reduce wasp populations below 40% of the local population
- 123. What is Nevada Doing to Prevent Invasive Species? The Cooperative Agricultural Pest Survey (CAPS) program was created to detect and monitor invasive pests nationwide through annual surveys Survey targets include plant diseases, weeds, insects, nematodes, and other invertebrate organisms Nevada CAPS is cooperatively administered by USDA, NDA. Pest Tracker-Exotic Pest Reporting
- 124. What to Do if You Find a Suspected Invasive Insect? Contact Us! Jeff Knight Nevada Department of Agriculture 405 S. 21st Street Sparks NV 89431 (775) 353-3767 Gene Phillips Nevada Division of Forestry 2478 Fairview Drive Carson City, Nevada 89701 Phone: 775-849-2500 ext 241 Heidi Kratsch University of Nevada Cooperative Extension Washoe County 4955 Energy Way Reno, NV 89502 Phone: 775-784-4848 If you are able to collect the suspected insect, it is very important that you kill the insect (don’t squish it!) to avoid its spread. Place the insect into a spill-proof vial containing alcohol (rubbing or other) or white vinegar. Include with the vial: Date Location (street address or GPS location) The plant that was affected (if applicable) Your contact information in case we have follow-up questions Secure the sample using packing material to avoid breakage/damage, and then mail the sample to us
- 125. RESOURCES http://www.nrs.fs.fed.us/tools/afpe/ http://foresthealth.fs.usda.gov/portal/Flex/APE http://foresthealth.fs.usda.gov/portal/Flex/FPC
Editor's Notes
- Newly deposited eggs are cream-colored, but turn reddish-brown as they develop
- NEED PHOTO
- Several gen a yr
- WTB is believed to have 2 to 3 generations a year in California. Adults emerge for an initial flight period in April and May followed by a longer second generation flight period in mid-July to mid-September. After flying, male beetles initiate brood galleries on branches often near leaf scars or lenticels. Males produce a pheromone and attract 2 to 3 females, which attract additional beetles to the tree. Females deposit eggs in galleries (tunnels) that are directed against the grain and constructed in the phloem and xylem (wood) surfaces. The gallery imprint is left on the wood surface. Small white C-shaped larvae hatch and create feeding mines that extend from the egg galleries. These mines are contained in the phloem and filled with dark brown to black-colored boring dust. Larvae complete development in the mines and subsequently pupate within a single pupal cell. Adults emerge and either remain at the original tree or fly to other trees to mate and reproduce. WTB does not appear to be attracted to stressed or injured branches or trees. Beetles are believed to inoculate the Geosmithia sp. fungus into the phloem during construction of feeding or reproductive galleries. The fungal pathogen colonizes and kills the phloem. Dead tissue is limited to the phloem and cambium and the fungus does not penetrate woody tissues. Secondary saprophytic fungi may opportunistically colonize the wood beneath cankers.
- Ohio not reported here
- DED-spores on emerging beetles, feed in healthy tree, construct galleries, spores in galleries. Fungal conidia present in galleries, spores stick to adults as they exit, beetles bore into bole, fungus enters tree, travels to sapwood, blocks vascular system, tree wilts
- Three species of bark beetles are associated with elms in the United States: (1) the native elm bark beetle (fig. 1) occurs in Canada and south through the Lake States to Alabama and Mississippi, including Kansas and Nebraska; (2) the introduced smaller European elm bark beetle (fig.2) occurs throughout the United States; and (3) the introduced banded elm bark beetle (fig. 3) is common in western states and is spreading into states east of the Mississippi River.
- BEBB overwinter underneath the bark either as mature larvae, pupae or adults. It takes 40-45 days to complete a life cycle, and there may be 2-3 overlapping generations a year. New adults emerge in early spring and begin feeding in the crotches of tender twigs. Adults are most active on warm, sunny afternoons. Females excavate entrance holes in the bark of elm trees, mate there with males, then construct a single vertical egg gallery about 2-3.5” (5-9 cm) long in the cambium underneath the bark. Galleries contain an average of 60 individual egg niches (range: 23-123) closely arranged along each side of the gallery wall, sealed with a mixture of sawdust and adhesive secretions. Newly hatched larvae feed under the bark, constructing individual mines somewhat perpendicular to the sides of the egg gallery, which eventually meander up, down, and even across each other. The larval stage is the most destructive as larvae feed on the cambium (growth cells) and phloem layers (food conduction tissue) under the bark, and high larval densities can lead to complete girdling of the cambium. Larvae eventually move to just under the outer layer of bark to pupate in chambers constructed at the ends of the galleries. All life stages of BEBB may be present later in the summer.
- What to Look For: BEBB usually attack elms weakened and stressed by drought, and prefer trees over 4 years old with trunks or branches greater than 2.0” (> 5 cm) in diameter. BEBB are capable of killing mature, drought-stressed elms, and during outbreaks may attack healthy elms. Symptoms of BEBB infestation include: • Wilted and/or fading foliage and branch breakage. • Small round entrance/exit holes 0.06-0.08” (1.6-2.0 mm) in diameter, in the bark. • Sawdust and occasionally sap flow may be found on the bark near entrance holes. • Bark may easily slough off or be peeled away due to larvae feeding on the inner bark. • Repeated attacks on declining trees can lead to tree death.
- What to Look For: BEBB usually attack elms weakened and stressed by drought, and prefer trees over 4 years old with trunks or branches greater than 2.0” (> 5 cm) in diameter. BEBB are capable of killing mature, drought-stressed elms, and during outbreaks may attack healthy elms. Symptoms of BEBB infestation include: • Wilted and/or fading foliage and branch breakage. • Small round entrance/exit holes 0.06-0.08” (1.6-2.0 mm) in diameter, in the bark. • Sawdust and occasionally sap flow may be found on the bark near entrance holes. • Bark may easily slough off or be peeled away due to larvae feeding on the inner bark. • Repeated attacks on declining trees can lead to tree death.
- What to Look For: BEBB usually attack elms weakened and stressed by drought, and prefer trees over 4 years old with trunks or branches greater than 2.0” (> 5 cm) in diameter. BEBB are capable of killing mature, drought-stressed elms, and during outbreaks may attack healthy elms. Symptoms of BEBB infestation include: • Wilted and/or fading foliage and branch breakage. • Small round entrance/exit holes 0.06-0.08” (1.6-2.0 mm) in diameter, in the bark. • Sawdust and occasionally sap flow may be found on the bark near entrance holes. • Bark may easily slough off or be peeled away due to larvae feeding on the inner bark. • Repeated attacks on declining trees can lead to tree death.
- What to Look For: BEBB usually attack elms weakened and stressed by drought, and prefer trees over 4 years old with trunks or branches greater than 2.0” (> 5 cm) in diameter. BEBB are capable of killing mature, drought-stressed elms, and during outbreaks may attack healthy elms. Symptoms of BEBB infestation include: • Wilted and/or fading foliage and branch breakage. • Small round entrance/exit holes 0.06-0.08” (1.6-2.0 mm) in diameter, in the bark. • Sawdust and occasionally sap flow may be found on the bark near entrance holes. • Bark may easily slough off or be peeled away due to larvae feeding on the inner bark. • Repeated attacks on declining trees can lead to tree death.
- The Sirex woodwasp has a sturdy, cylindrical body without a waist, but with a pointed abdomen. The female body is 15–36 mm (0.59–1.42 in), and the male is 9–32 mm (0.35–1.26 in) long. Both sexes have long, black, bristle-shaped antennae, which are rather close together.[3][7] The body of the male is black, except for the orange middle part of the abdomen. The wings are yellowish-translucent and the antennae are black. The front pair of legs has a yellowish-orange colour, the back pair is heavily thickened and is coloured black on the posterior splint and tarsus, while the femur is orange.[3][7] The females are iron blue, and have orange legs and black antennae. This is a notable distinction from Sirex juvencus, which has red antennae. The females also have yellowish wings. The ovipositor is below the tapering tip of the abdomen. The sting is connected with the mycetangia, which are special organs on the abdomen, where the female stores the oidiae (asexual fungus spores), from broken segments of hyphae. These spores are deposited, together with the eggs, in the host tree wood to germinate. Both larvae and adults have strong mandibles and can drill through lead plates
- The Sirex woodwasp has a sturdy, cylindrical body without a waist, but with a pointed abdomen. The female body is 15–36 mm (0.59–1.42 in), and the male is 9–32 mm (0.35–1.26 in) long. Both sexes have long, black, bristle-shaped antennae, which are rather close together.[3][7] The body of the male is black, except for the orange middle part of the abdomen. The wings are yellowish-translucent and the antennae are black. The front pair of legs has a yellowish-orange colour, the back pair is heavily thickened and is coloured black on the posterior splint and tarsus, while the femur is orange.[3][7] The females are iron blue, and have orange legs and black antennae. This is a notable distinction from Sirex juvencus, which has red antennae. The females also have yellowish wings. The ovipositor is below the tapering tip of the abdomen. The sting is connected with the mycetangia, which are special organs on the abdomen, where the female stores the oidiae (asexual fungus spores), from broken segments of hyphae. These spores are deposited, together with the eggs, in the host tree wood to germinate. Both larvae and adults have strong mandibles and can drill through lead plates
- The Sirex woodwasp has a sturdy, cylindrical body without a waist, but with a pointed abdomen. The female body is 15–36 mm (0.59–1.42 in), and the male is 9–32 mm (0.35–1.26 in) long. Both sexes have long, black, bristle-shaped antennae, which are rather close together.[3][7] The body of the male is black, except for the orange middle part of the abdomen. The wings are yellowish-translucent and the antennae are black. The front pair of legs has a yellowish-orange colour, the back pair is heavily thickened and is coloured black on the posterior splint and tarsus, while the femur is orange.[3][7] The females are iron blue, and have orange legs and black antennae. This is a notable distinction from Sirex juvencus, which has red antennae. The females also have yellowish wings. The ovipositor is below the tapering tip of the abdomen. The sting is connected with the mycetangia, which are special organs on the abdomen, where the female stores the oidiae (asexual fungus spores), from broken segments of hyphae. These spores are deposited, together with the eggs, in the host tree wood to germinate. Both larvae and adults have strong mandibles and can drill through lead plates
- Adult wasps emerge June through September, with peak emergence in August. The adult SWW bores out of the tree leaving a characteristic round exit-hole which varies in diameter according to the size of the wasp. Adults live one to three weeks and do not feed, living off of fat stored in their bodies. Females are attracted to stressed pine trees and can begin laying eggs one day after emergence. If the female does not mate with a male, she will lay eggs that produce only male offspring; if she does mate, eggs will produce both male and female offspring. The biology of siricid woodwasps is a complex interaction between several organisms: the woodwasp and toxic mucus produced by the adult female, a symbiotic wood-decaying fungus, and the host tree. Newly pupated adult female woodwasps take up spores of the symbiotic fungus, Amylostereum areolatum, from their host trees as they emerge and carry them in specialized abdominal glands called mycangia. When a female is ready to lay eggs, she drills her ovipositor into the outer sapwood, simultaneously injects toxic mucus, and deposits a single egg. Drill holes are perfectly round, usually located on the sunny side of trees, and may occur singly or in a cluster of 5 or 6 “drills” together. If several drills are clustered, one usually lacks an egg and instead is packed with spores of the symbiotic fungus. A single female may lay 25-450 eggs, averaging about 212. The toxic mucus disables the tree’s network for transporting water and nutrients, causing the foliage to wilt and yellow. This creates ideal conditions for the development and spread of the fungus, which invades the vascular system of the tree, dries out the wood and breaks down cellulose. The mucus and fungus acting together lead to the death of the tree and engender favorable conditions for eggs to hatch, while also providing food for developing larvae. The fungus feeds on the killed wood, and the larvae actually feed on the fungus. Larvae hatch from the eggs after a minimum of nine days, but in cooler climates eggs may remain dormant for several months or even over the winter. As larvae grow, they bore galleries deep into and through the wood. There are usually six larval instars, and it takes about 10-11 months to complete the larval stage. Mature larvae pupate close to the bark surface, and adults emerge about 3 weeks later.
- SWW are most likely to infest weak, injured, diseased, very rapidly growing, or otherwise stressed living host trees, and dead or fallen host trees. Symptoms of SWW infestation include: • Foliage wilts and the needles point straight down. • Needles in tree crowns turn light green to yellow to reddish brown over 3-6 months. • Resin beads or dribbles on the bark from oviposition drilling wounds. • Oviposition drill holes are perfectly round, usually clustered in groups of 5 or 6. • Drill sites are more common at mid-bole level (10-30+ ft or 3-9+ m) on trees 6-8” (> 15 cm) in diameter and larger. • Meandering larval galleries abut 5-6” (12-15 cm) long, tightly packed with frass, expanding in diameter as they progress. • Galleries initiate in the cambium, then turn in toward the heartwood, and may turn back out toward the bark prior to pupation. • Larvae may be found in galleries beneath the bark, deep into heartwood, or deep in oviposition drill holes. • Pupae are typically found in chambers about 2” (5 cm) below the surface of the bark. • Fungal staining of the cambial layer beneath the bark. Stains are long, narrow, oval shaped brown bands along the grain, with drill hole(s) at the center. • Round exit holes ⅛-⅜” (3-8 mm) in diameter created by adults emerging in year two.
- The Sirex woodwasp has a sturdy, cylindrical body without a waist, but with a pointed abdomen. The female body is 15–36 mm (0.59–1.42 in), and the male is 9–32 mm (0.35–1.26 in) long. Both sexes have long, black, bristle-shaped antennae, which are rather close together.[3][7] The body of the male is black, except for the orange middle part of the abdomen. The wings are yellowish-translucent and the antennae are black. The front pair of legs has a yellowish-orange colour, the back pair is heavily thickened and is coloured black on the posterior splint and tarsus, while the femur is orange.[3][7] The females are iron blue, and have orange legs and black antennae. This is a notable distinction from Sirex juvencus, which has red antennae. The females also have yellowish wings. The ovipositor is below the tapering tip of the abdomen. The sting is connected with the mycetangia, which are special organs on the abdomen, where the female stores the oidiae (asexual fungus spores), from broken segments of hyphae. These spores are deposited, together with the eggs, in the host tree wood to germinate. Both larvae and adults have strong mandibles and can drill through lead plates
- Biological Control Sirex woodwasp has been successfully managed using biological control agents. The key agent is a parasitic nematode, Deladenus siricidicola, which infects sirex woodwasp larvae, and ultimately sterilizes the adult females. These infected females emerge and lay infertile eggs that are filled with nematodes, which sustain and spread the nematode population. The nematodes effectively regulate the woodwasp population below damaging levels. As sirex woodwasp establishes in new areas, this nematode can be easily mass-reared in the laboratory and introduced by inoculating it into infested trees. In addition to the nematode, hymenopteran parasitoids have been introduced into sirex woodwasp populations in the Southern Hemisphere, and most of them are native to North America (e.g., Megarhyssa nortoni, Rhyssa persuasoria, Rhyssa hoferi, Schlettererius cinctipes, and Ibalia leucospoides).