Systemic Insecticide Technology for Tree Care -...Systemic
Transcription
Systemic Insecticide Technology for Tree Care -...Systemic
Systemic Insecticide Technology for Tree Care Dan Herms Department of Entomology The Ohio State University Ohio Agricultural Research and Development Center Wooster herms.2@osu.edu Landscapes are diverse ecosystems Advantages of systemics: • Effective control of diversity of pests. • Timing: fall or spring. • Diverse application methods. Can be used where spraying is undesirable. • Very low use rates: low environmental risk. • Very low vertebrate toxicity. • Reduced impact on natural enemies. Advantages of systemics: • Effective control of diversity of pests. • Timing: fall or spring. • Diverse application methods. Can be used where spraying is undesirable. • Very low use rates: low environmental risk. • Very low vertebrate toxicity. • Reduced impact on natural enemies. • But – they have to be applied preventively. Questions: Selectivity: which pests are controlled? Patterns of uptake, translocation, and accumulation in the plant? Length of residual activity? Timing: fall vs. spring vs. summer? Application rate vs. tree size? Placement? Systemic Insecticides: Soil Systemic vs. Foliar Translaminar Soil Systemic Activity Systemic Activity? True Systemic Activity? Translaminar Activity Systemic Insecticides Soil Drench / Injection: • Acelepryn • Acephate (Lepitect) • Clothianidan (Arena) • Dinotefuran (Safari, Transect) • Imidacloprid (e.g. Merit, Xytect, Bayer Advanced Tree & Shrub Insect Control) Systemic Trunk Injections: • Acephate (Acecap) • Emamectin benzoate (TREE-äge) • Imidacloprid (IMA-jet, Imicide, Pointer) Systemic Trunk Sprays • Dinotefuron (Safari) Soil Treatments: Drench / Injections Trunk Injections Systemic Basal Trunk Sprays Selectivity: Imidacloprid is effective against: Sucking insects: plant bugs, lace bugs, adelgids, aphids, soft scales, psyllids (but not armored scales) Defoliators: sawflies, leaf beetles, Japanese beetle, (but not caterpillars) Leafminers: sawflies, dipterans Borers: flatheaded and roundheaded borers (but not clearwing borers) Selectivity: Acelepryn Controlled: Gypsy moth Rhododendron lace bug Birch leafminer Magnolia scale (fall not spring) Clearwing borers Did not control: Mimosa webworm Bagworm Holly leafminer Emerald ash borer Systemics for Control of Wood Borers Bronze birch borer Emerald Ash Borer Host Impact: Larvae feed under bark; disrupt transport of water, nutrients, carbohydrates. All major ash species are susceptible (white, green, black, blue, pumpkin). Healthy trees killed within 2-3 years of first symptoms. Trees of all size are susceptible: 1/2 inch saplings to the largest mature trees. A Toledo street before and after EAB June 2006 August 2009 Systemic Insecticide options for EAB: Systemic Soil Injections / Drenches: • Imidacloprid (e.g. Merit, Xytect, Bayer Advanced Tree & Shrub Insect Control) • Dinotefuran (Safari, Transect) Systemic Trunk Injections: • Imidacloprid (IMA-jet, Imicide) • Emamectin benzoate (TREE-äge) Systemic Trunk Sprays • Dinotefuron (Safari, Transect) Deb McCullough, MSU Trees treated in 2007 & 2008 120 a EAB larvae per m2 100 ab 80 abc 60 abc bc bc 40 c 20 0 Ctrl Dino Dino-PB Em Ben Imid Imid-PB Maug-imi Deb McCullough, MSU Emamectin benzoate (Tree-age): 2 years control with a single injection. Trees treated in 2007 EAB larvae per m2 120 a 100 80 a a a a a 60 40 b 20 0 Ctrl Dino Dino-PB Em Ben Imid Imid-PB Maug-imi Objective: multi-year evaluation of systemic insecticides for control of EAB on street trees • Imidacloprid soil drenches • Imidacloprid and Emamectin Benzoate trunk injections Trial 1: Imidacloprid Soil Drenches 1. Merit 2F, 1.4 g ai / inch DBH, spring 2. Merit 2F, 1.4 g ai / inch DBH, fall 3. Xytect 75WP, 1.4 g ai / inch DBH, fall 4. Xytect 75WP, 2.8 g ai / inch DBH, spring 5. Xytect 75WP, 2.8 g ai / inch DBH, fall Treatment evaluation: • Canopy decline rating using photographic scale (Smitley et al. 2008. J. Econ. Entomol. 101:1643-1650) • Exit hole density in canopy branches. 2008 2009 Four years of imidacloprid soil drenches (D. Smitley, MSU) Trial 2: Systemic trunk injections, product comparison Emamectin benzoate (Tree-äge) Rate: 0.4 g ai / inch DBH 1. 2006 2. 2006 & 2008 Imidacloprid (Ima-jet), Rate: 0.4 g ai / inch DBH 1. 2006 & 2007 2. 2006 & 2008 Systemic Trunk Injections for Control of EAB % Canopy Decline Treatment 2006 2007 2008 2009 Untreated 0 6 51 a 90 a Tree-äge, 2006 0 0 0b 13 c Tree-äge, 2006 & 2008 0 0 3b 6c Ima-jet, 2006 & 2007 0 0 0b 33 b Ima-jet, 2006 & 2008 0 0 9b 20 bc Systemic Trunk Injections for Control of EAB Exit holes / m2 Treatment 2008 2009 Untreated 15.3 a 34.7 a Tree-äge, 2006 0.1 b 1.9 c Tree-äge, 2006 & 2008 0.1 b 0.6 c Ima-jet, 2006 & 2007 0.1 b 3.8 c Ima-jet, 2006 & 2008 4.4 b 11.9 b Trial 3: Systemic trunk injections, rate comparison Emamectin benzoate (Tree-äge) 0.1 g ai / inch DBH 0.2 g ai / inch DBH 0.4 g ai / inch DBH 0.8 g ai / inch DBH Imidacloprid (Ima-jet) 0.4 g ai / inch DBH Treat in 2006 and see how long they work. Effect of Emamectin Benzoate Applied in 2006 for Control of EAB % Canopy Decline Treatment Untreated 2006 2007 2008 2009 0 8 53 a 96 a 0.1 g ai / inch DBH 0 0 3b 13 bc 0.2 g ai / inch DBH 0 0 3b 38 b 0.4 g ai / inch DBH 0 0 10 b 38 b 0.8 g ai / inch DBH 0 0 0b 5c 0 0 8b 53 ab Emamectin benzoate Ima-jet, 0.4 g ai / inch DBH Effect of Emamectin Benzoate Applied in 2006 for Control of EAB Exit Holes / m2 Treatment 2008 2009 Untreated 19.2 a 24.6 a 0.1 g ai / inch DBH 0.2 b 2.9 c 0.2 g ai / inch DBH 0.5 b 10.1 ab 0.4 g ai / inch DBH 1.4 b 3.3 c 0.8 g ai / inch DBH 0.0 b 0.5 c Emamectin benzoate Trunk Injections vs. Soil Treatments Soil treatments: Non-invasive. More uniform distribution in the tree. Can be applied under diverse environmental conditions. Can be applied during dormant season. Slower uptake. No way to know how much uptake. Don’t require specialized equipment. Trunk injections: Less environmental exposure. Faster uptake and distribution in tree. May be more effective on larger trees. Rate of uptake is weather dependent. Invasive: wounding and compartmentalization. Optimal Timing of Treatments • Soil treatments: in spring allowing time for uptake before adults begin feeding and eggs begin to hatch. Fall treatments can also be effective. • Trunk injections: in spring just after the canopy has fully developed EAB adult emergence begins when black locust blooms. Black locust, Robinia pseudoacacia www.oardc.ohio-state.edu/gdd Google: “OSU degree-day website” Banded Ash Clearwing Borer Banded Ash Clearwing Borer Emamectin Benzoate Controls Banded Ash Clearwing Borer Soil Drenches: 8” DBH Street Trees Treatment Untreated control Merit 2F Bayer Advanced TSIC Imidacloprid + Clothianidin Acelepryn, fall Acelepryn, spring % Decline 41 5 12 14 37 52 Chief Conclusions: 1. Insecticides can control EAB on large caliper trees even under intense pest pressure. 2. Imidacloprid soil drenches are most effective on large trees when applied at the 2X (2.8 g ai / inch DBH) rate. Xytect is the only product currently labeled at this rate. 3. Soil drenches must be applied annually. 4. A single application of Emamectin Benzoate can provide three, and possibly four, years of control. 5. Emamectin benzoate also controls banded ash clearwing borer. Bark Beetles Imid a c lo p rid So ilDre n c h e s f r Co n tro l o f Pi n e Ba rk Be e tl e s o % Control 100 Ev a l u a te d J u l y 2 0 0 4 80 60 40 20 0 June 2003 Nov 2003 Mer it 75 WP Apr il 2004 Nov 2003 Bayer Advanced Tr ee and Shr ub Insecticides to not control blue stain fungi White Pine Weevil Soft Scales: phloem sap Magnolia Scale Calico Scale Imid a c lo p rid fo r Co n tro l o f Ca l i c o Sc a l e % Surv iv al 100 a 80 b 60 40 20 c 0 Cont r ol Bayer Advanced Tr ee and Shr ub I micide Application: 14 June Evaluation: 10 September Calico scale nymphs on untreated control (left) and Imicide treated (below) honeylocust trees Armored scales: • Oystershell scale • Pine needle scale • Euonymus scale Euonymus scale feeding sites: Intracellular (palisade, spongy mesophyll) C.S. Sadof and J.J Neal. 1993. Ann. Entomol. Soc. Am. 86:614620 (Figs. 1-3). Pine needle scale Al l e c tu s fo r Co n tro l o f M o l te d Pi n e Ne e d l e Sc a l e % Control 100 80 60 40 20 0 Alect us 1% Oil Alect us + 1% oil Boxwood Psyllid Imid a c lo p rid So ilDre n c h e s fo r Bo x wo o d Ps y l l i d 100 % Control 80 60 40 20 0 May 2001 Dec 2001 Mer it 75 WP Dec 2001 Bayer Advanced Tr ee and Shr ub Evaluated May 2002 Lace Bugs Acephate (Lepitect) as a systemic soil treatment for spider mites Defoliators Imidacloprid controls sawflies but not caterpillars. Bt controls caterpillars but not sawflies. European pine sawfly European pine sawfly survival in bioassays one year post treatment (May 2001) 100 % s urv iv al 1 No v 1 9 9 9 80 1 Ap r 2 0 0 0 60 40 20 0 Cont r ol Mer it 75WP Flagship 25WG Birch leafminer No control of birch leafminer one year post treatment (May 2001) Gypsy moth Acephate (Lepitect) soil drenches controlled gypsy moth on small caliper but not large caliper trees Japanese Beetle Acephate (Lepitect) soil drench provided excellent control of Japanese Beetle Soil applications for control of black vine weevil larvae Timing: fall vs. spring? Uptake by “dormant” deciduous trees Honeylocust plant bug Im id ac lo prid s o iln je c tio ns fo r pl ant bugon la rg e c alip er( honey l oc us t 24") trees Insects / sample 25 20 a 15 10 5 b 0 Untreated 24October Evaluated on 6 May Length of residual activity? Birch leafminer No control of birch leafminer one year post treatment (May 2001) European pine sawfly European pine sawfly survival in bioassays one year post treatment (May 2001) 100 % s urv iv al 1 No v 1 9 9 9 80 1 Ap r 2 0 0 0 60 40 20 0 Cont r ol Mer it 75WP Flagship 25WG Length of residual activity? Residual toxicity? or Lack of recolonization? Placement? Fine root density is highest adjacent to the trunk. How much water to apply? Balancing the trade-off. • Not enough water: poor distribution • Too much water: dilutes the soil solution, which may reduce uptake rate and concentration in the plant www.ashalert.osu.edu herms.2@osu.edu