Management of Wood Boring Insects. Whitney Cranshaw Colorado State University

Transcription

1 Management of Wood Boring Insects Whitney Cranshaw Colorado State University

2 Several Insects Work as Borers Some beetle larvae Flatheaded borers/metallic wood borers Roundheaded borers/longhorned beetles Some moth larvae Clearwing borers Carpenterworms Pyralid borers Some wasp larvae Horntails

3 Flatheaded Borers/ Metallic Wood Borers Coleoptera: Buprestidae

4 Flatheaded Borer

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9 Thinning of the crown is a common symptom of flatheaded borer infestation

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11 Pupation occurs under the bark

12 Photo sequence by David Shetlar, Ohio State University

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15 D-Shaped Exit Hole Produced by Emerging Metallic Wood Borer

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17 Metallic Wood Borer, Adult Form of a Flatheaded Borer

18 Metallic Wood Borer - Adult form of a Flatheaded Borer

19 Some metallic wood borers have bright coloration

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21 Four Agrilus sp. Borers found in Colorado Top Row - Rose stem girdler (left), Bronze birch borer (right) Bottom Row Honeylocust borer (left), Gambel oak borer (right)

22 D-Shaped Exit Hole Produced by Emerging Metallic Wood Borer

23 Diagnosis Flatheaded Borer Injury Meandering tunnels produced under the bark Tunnels packed with fine sawdust Plant shows decline/thinning crown D-shaped exit holes in bark

24 Roundheaded Borers/ Longhorned Beetles Coleoptera: Cerambycidae

25 Pine Sawyers

26 Cottonwood Borer

27 Banded Alder Borer

28 Locust Borer

29 Poplar Borer

30 Dave Leatherman Ponderous Borer Dave Leatherman

31 Roundheaded Borer

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34 Coarse sawdust expelled from tree by roundheaded borer

35 Locust Borer tunneling Photographs by David Leatherman

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37 Life stages of a poplar borer Photograph courtesy John Ghent/IPM Images

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39 Diagnosis Roundheaded Borer Injury Tunneling penetrates into heartwood of the tree Riddling, structural weakening Coarse sawdust typically produced Oval exit holes in bark

40 Clearwing Borers Lepidoptera: Sesiidae

41 Some Common Clearwing Borers of Colorado Peach tree borer (Prunus spp.) Lilac/Ash borer (ash, lilac, privet) Currant borer (Ribes spp.) Viburnum borer (Viburnum spp.) Raspberry crown borer (raspberry) Cottonwood crown borer (Cottonwood)

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43 Peach tree borer larval tunneling in base of plant

44 Top: Peach tree borer larva Right: Prolegs on the abdomen, tipped with hooked crochets, are characteristic of borers that develop into moths (Order Lepidoptera)

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46 Small hooks on the underside of the abdomen (crochets) indicate the larva is a type of moth. Beetles do not have prolegs on the abdomen with these hooks.

47 Upper left: Peach tree borer female Upper right: Peach tree borer male Lower left: Pupal skin extruded from case of silk and wood fragments

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50 Raspberry crown borer larva in base of raspberry

51 Raspberry crown borer adults mimics of yellowjacket wasps

52 Lilac/Ash borer adult mimic of a paper wasp

53 Lilac/ash borer injury to base of ash - exterior

54 Lilac/ash borer damage to base of ash -interior

55 Lilac/ash borer larvae

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57 The pupal skin often extrudes when the adult emerges

58 Exit holes are slightly oval, nearly round

59 Lilac/Ash Borer Mating Pair

60 Diagnosis Clearwing Borer Injury Tunneling often concentrated at the base (root crown) of the plant Tunneling an irregular gouging Pupal skins often are pulled out upon adult emergence

61 Wood Borer Management Optimize conditions for plant growth Sanitation Preventive applications of insecticides

62 Plant Health Care and Wood Borer Prevention Proper selection of plant material Appropriate siting in the landscape Good site preparation, planting conditions Provision of adequate watering Note: Fertilization can produce mixed effects on borer resistance

63 Example: Birch and bronze birch borer

64 Wood Borers and Plant Stress Plant defensive responses are diminished Related to stored photosynthate and water availability Plants may be slightly more attractive to adults when they lay eggs

65 Sanitation and Wood Borers Elimination of potential brood wood Prune-out of infested wood Proper disposal of infested wood is important.

66 Preventive Use of Insecticides Treatments are not available for borers currently in a plant

67 Preventive Use of Insecticides Timed for Egg Laying/Egg Hatch Period!

68 Evidence of adult borer activity observation of the adults on plants

69 Evidence of borer adult activity fresh exit holes

70 Evidence of clearwing borer adult activity new pupal skins

71 For most borers flight periods can be estimated Fact Sheet (Borers) or Bulletin 506A

72 Approximate flight periods of some wood borers Lilac/Ash borer early May Bronzed birch borer (and other Agrilus spp.) mid-june Poplar borer late June Peachtree borer early July Locust borer mid-august

73 Pheromone Traps A tool for monitoring some insects

74 Pheromones and Insect Management Pheromones are chemicals used to communicate between members of the same species Insects use many kinds of pheromones Sex Aggregation Alarm and many other things Sex pheromones of some moths are used in pest management

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77 Pheromone trap data for lilac ash borer

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79 Active Ingredients of Wood Borer Insecticides Permethrin (Astro, etc.) Carbaryl (Sevin) Bifenthrin (Onyx, Talstar, etc.) Acelypryn Imidacloprid Soil applied drench

80 Key Timing Point in Wood Borer Prevention Egg Laying/Egg Hatch (Coincident with adult activity)

81 Acelepryn New class of insecticides anthrinilic diamides Derivatives of ryania (natural product) Activity against most chewing insects Labels being developed for both turfgrass and woody ornamentals

82 Acelepryn Very low toxicity to vertebrates LD50 greater than 5000 mg/kg Class 4 No Caution label Protective equipment Long sleeved shirt, long pants Shoes with socks

83 Acelypryn labeled use Lace bugs (soil treatment)

84 Acelypryn labeled use Caterpillars (foliar treatment)

85 Acelepryn labeled use clearwing borers (trunk spray)

86 Future of Acelepryn? Low risk a huge plus Soil-applied systemic activity a huge plus but poorly understood Activity probably includes most leaf chewing insect groups Activity as wood borer treatment very good (clearwing borers and others?)

87 Active Ingredients of Wood Borer Insecticides Permethrin (most available) Carbaryl/Sevin (limited availability) Bifenthrin (no over-the-counter products at present) Imidacloprid Soil applied drench - systemic insecticide Only effective against flatheaded borers

88 Imidacloprid for Borers? Yes..but

89 Imidacloprid will not work well on borers that are the larval stage of moths (i.e. insect order Lepidoptera)

90 Peach tree borer larval tunneling in base of plant

91 Zimmerman pine moth injury

92 Imidacloprid soil drenches will work poorly against roundheaded borer larvae that spend little time in cambium

93 Imidacloprid soil drenches will work poorly against flatheaded borer larvae after they have caused extensive damage

94 Imidacloprid soil drenches may work well against flatheaded borer larvae (aka metallic wood borers) if the plant has not already been badly damaged

95 Four Agrilus spp. borers Top Row - Rose stem girdler (left), Bronze birch borer (right) Bottom Row Honeylocust borer (left), Emerald ash borer (right) Dan Herms David Cappaert

96 Some Currently Used Neonicotinoid Insecticides Imidacloprid (Merit, Marathon, Criterian, Provado, Admire - many generics) Clothianidin (Celero, Arena, etc.) Dinotefuran (Safari)

97 Relative Water Solubility of Neonicotinoids: Water Solubility (Active Ingredient) Clothianidin Imidacloprid Acetamiprid Thiamethoxam Dinotefuran 0 Slide information courtesy J. Chamberlin

98 Dinotefuran 26 Thiamethoxam K oc Values of Neonicotinoids: Acetamiprid Imidacloprid Clothianidin Source Data: EPA Pesticide Fact Sheets

99 Implications for Dinetofuran (Safari) Soil Applications Dinotefuran requires moist soils for uptake Can move through thin bark Uptake into plant is relatively fast Ability to control aphids in days Persistence in plant much shorter than other neonicotinoids

100 Safari trunk sprays have been developed as a tool to manage emerald ash borer

101 Bark Beetles Coleoptera: Curculionidae (Scolytinae)

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103 Mountain Pine Beetle Dendroctonus ponderosae

104 Western Pine Beetle Photograph courtesy of Ladd Livingston/IPM Images

105 Friday Seminar 9:00 What s Happening in Idaho s Forests Carl Jorgenson USDA Forest Service

106 Thousand Cankers Disease (TCD) An Insect/Fungal Disease Complex affecting some Juglans spp.

107 A fungus Geosmithia morbida A beetle walnut twig beetle

108 Jim LaBonte Walnut Twig Beetle Pityophthorous juglandis Jim LaBonte

109 Adults enter trees and excavate galleries

110 Larval feeding produces a loose network of meandering tunnels in the cambium

111 A full grown larva, preparing to pupate.

112 Teneral adults and pupa, covered with Geosmithia spores

113 The Pathogen - Geosmithia morbida

114 Geosmithia is introduced into wounds made by walnut twig beetles

115 Growth of the fungus beyond the inoculation site creates a dead region (canker) in the cambium.

116 Multiple cankers produce girdling that seriously restricts movement of nutrients.

117 Flagging symptoms emerge in end stages of 1000 cankers on black walnut

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119 Foliage wilting may occur rapidly on TCD-compromised limbs

120 Crown symptoms July 2009 Tree died in 2010

121 September 2008 June 2008 June 2009

122 Walnut twig Death beetle exit holes by TCD Working Hypothesis Girdling from cankers (and bark beetle tunneling) restricts movement of nutrients. Trees weaken as stored energy reserves become depleted. External symptoms develop in end stages of infestations Trees ultimately die from energy depletion.

123 Symptoms of Thousand Cankers Disease develop following sustained introductions of Geosmithia by walnut twig beetles in susceptible hosts.

124 Origin of Thousand Cankers Disease

125 The walnut twig beetle was originally described (1928) from Arizona walnut, Juglans major. Great picture by Jim LaBonte, OR Dept. Agriculture! Original collections of the beetle were made in 1896.

126 Published distribution of Arizona walnut

127 Arizona walnut (Juglans major) Host associated with original descriptions of the walnut twig beetle

128 Arizona walnut is a common species found in canyons and along riverways

129 In surveys, walnut twig beetle was repeatedly found in Arizona walnut at several sites in NM and AZ

130 Walnut twig beetle in AZ walnut functions as a typical Pityophthorus species of twig beetle. Attacks are normally limited to small diameter branches and function as a form of natural pruning.

131 Progression to fullblown Thousand Cankers Disease has not been observed in AZ walnut.

132 Geosmithia morbida is also likely to be a native fungus.

133 The Geosmithia fungus is has been found consistently associated with the tunnels and frass of walnut twig beetles regardless of Juglans spp. or site of collection.

134 Resistance to Thousand Cankers Disease may often result from differences in susceptibility to Geosmithia morbida Canker formation in black walnut Canker formation in Southern California walnut

135 How did this happen? - Somehow the beetle jumped hosts.

136 Walnut Twig Beetle Range Expansion Big Bang or Buttheads

137 Spread of walnut twig beetle through the western states involved human transport of infested wood products

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139 States reporting presence of walnut twig beetle -2009

140 Native Distribution of Black Walnut, Juglans nigra

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142 What I said last spring. Good News: Walnut twig beetle has likely not yet reached the native range of Juglans nigra (we think).

143 July 20, 2010 Very, very bad news: Thousand cankers and walnut twig beetles found in the center of the native range of Juglans nigra Knoxville, Tennessee Note: The local foresters thought that the trees were suffering from drought stresses

144 Thousand Cankers has now breached the geographic barrier of the Great Plains!!!!

145 Implications of TCD Finding in Native Range There are now no ecological or geographic barriers that will prevent TCD spread throughout the entire range of Juglans nigra Natural spread will be slow (comparably) but inexorable Containment through restrictions on movement of walnut wood products may slow spread Aggressive management at edges of infestation may slow spread

146 Slow the Spread of Thousand Cankers Disease!

147 Good News: Other Juglans species are not as susceptible to TCD as is Juglans nigra (black walnut). Pecan (Carya) are apparently TCD resistant.

148 Good News: It takes a long time (Decade? More? A bit less?) for a tree to die following initial colonization by walnut twig beetles.

149 Bad News: By the time symptoms appear it can be assumed that the walnut twig beetle is generally distributed in the area.

150 Bad News: Prospects for effective chemical control of walnut twig beetle are poor.

151 Drenching branch sprays for walnut twig beetle Treatments have failed to slow progress of thousand cankers in trees showing symptoms

152 Systemic insecticide soil drenches/ trunk injections? The fungus grows ahead of the beetle. Cankered areas may prevent movement of insecticide to the beetle feeding site.

153 Thousand Cankers Management & Pesticides What kind of crop is black walnut?

154 Pesticides Used on Black Walnut Must Probably legal Imidacloprid Chlothianidin be Consistent with Labels for Nutbearing Crops Not apparently legal for use on black walnut Dinotefuran Abamectin Enamectin benzoate

155 Bad News: Prospects for effective control of walnut twig beetle are poor. Insecticides may slightly slow, but will not stop the progress of TCD.

156 Bad News: Walnut wood with bark intact is extremely infectious.

157 Two logs, ca 5 1/2-in diameter, 18-in length

158 23,040 Beetles/2 logs = 35+ Beetles/inch 2

159 Bad News: Long distance movement of walnut wood killed by 1000 cankers disease will be a huge issue due to the high value of the saw logs.

160 What about chipping?

161 Walnut twig beetles were able to complete development in larger pieces following chipping

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163 A walnut log in Denver waiting for Uncle Benny from Chicago

164 Beetle infested black walnut from Boulder area with bark attached as advertised on the internet

165 What Needs to Be Done Strong public education on the threat of Thousand Cankers Disease to black walnut in its native range Immediate restriction, aided by national quarantine, of all Juglans material that may spread walnut twig beetle into the native range of black walnut.

166 Immediate Action Needed: Institute quarantine of all Juglans wood of where thousand cankers is present X

167 A Juglans Quarantine Would affect logs/wood with bark intact Would not need affect Milled wood without bark Logs that have sufficiently dried so live beetles cease production (3 years?) Kiln-dried wood (questions remain about reinfestation potential) Nuts

168 States with Existing or Proposed TCD Quarantines Missouri Iowa Kansas Wisconsin? Michigan Indiana Nebraska North Carolina

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170 Slow the Spread of Thousand Cankers Disease!

171 TCD Training Workshops Many states are now trained in TCD diagnosis

172 An Interim Web Site for TCD information Department of Bioagricultural Sciences and Pest Management Colorado State University Click on Extension and Outreach