You. Insects. Remove cherry trees near pastures or paddocks

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1 Top 10 Notorious Landscape Pests (and How to Deal With Them) Daniel A. Potter, Professor University of Kentucky You # 9 & 10 Web making Caterpillars Fall webworm Insects Eastern tent caterpillar Mimosa webworm Non Chemical Control Bag nests in small trees Pole pruner Scrape off egg masses Tent Caterpillar outbreak of Tent caterpillars can cause horse abortions Mare Reproductive Loss Syndrome Remove cherry trees near pastures or paddocks Tree injection Bidrin Abacide 2 Not Treated Tree age Treated 1

2 #8 Bagworms Major Pest of Landscape Evergreens Bagworms Behaving Badly Male moths mate with female in late summer Female Eggs hatch, young bagworms begin feeding in May Female bagworm is wingless, legless; never leaves her bag Adult male is a furry moth that emerges in late summer Male Female lays eggs in her bag, where they overwinter Bagworm Control Tips Handpick bags with egg masses in winter or early spring and destroy Target small larvae with reduced risk insecticide in late May or June) Pyrethroid sprays will control all defoliating pests bifenthrin Reduced Risk Products for Defoliators Must match the product to the target! Controls caterpillars, beetles, and sawfly larvae cyfluthrin lambda cyhalothrin Bacillus thuringiensis: caterpillars only Controls caterpillars and sawfly larvae 2

3 #7 Sawfly Larvae Sawflies versus caterpillars Red headed Pine Sawfly S A W F L Y Sawfly: 6 or more pairs of fleshy abdominal prolegs (enough to spell SAWFLY) No little hooks on prolegs European Pine Sawfly Caterpillar: 5 or fewer pairs with little hooks Sawflies behaving badly Roseslug a Sawfly! Sawfly pupal cases (present in winter) Sawfly adult Controlling Sawflies Effective sprays include: Acelepryn Provaunt Pyrethroids Or, prune out small infestations! #6 Lacebugs, Leafminers, Psyllids Boxwood psyllid Boxwood leafminer Azalea lace bug Boxwood psyllid: cupped leaves Boxwood pests Boxwood leafminer 3

4 Boxwood Pests Lay Eggs in Expanding Young Leaves in Spring Lace bugs Lace bugs damage many plants: Adult Adult Sycamore Oak Hawthorn Nymphs on new growth Boxwood Psyllid Boxwood Leafminer Nymphs on Cotoneaster Pyracantha, cotoneaster, andromeda Azalea Lace Azalea Bugs Systemics are the way to go for lace bug, leaf miner, and psyllid control! #5 Mite Pests Warm Season Mites Fine webbing Twospotted spider mite European red mite Boxwood spider mite Tiny: about the size of a period (.) of 12 pt text Cool Season Mites Eight legs Leaf undersides Stippling Spruce spider mite Southern red mite Maple spider mite Spider Mite Symptoms Mite damage to burning bush Beating foliage over paper to dislodge and detect mites Stippled leaves Going. Going.. Bronzed or browned foliage Gone! 4

5 Mite Control Tips: Use a Miticide! (Most insecticides won t work for mites) Good ones include: Akari, Avid, Floramite, Forbid, Hexygon, Kontos, Promite, Pylon, Shuttle, Sanmite, TetraSan, Ultiflora Neonicotoids can flare mite problems on woody landscape plants Stimulates mite egg laying Kills natural predators Haircut for Potter s bug lectures Adults active from mid June to mid August Feed on >300 plant species! #4 Japanese Beetle Avoid Over planting Japanese Beetle Susceptible Species! July 8 July 18 Japanese Beetle Damage to Linden Tree, Lexington, KY, 2007 Susceptible: Linden Purple leaf plum Purple sandcherry Japanese maple Certain crabapples Roses Resistant: Red maple Dogwood Redbud Beech Tuliptree Sweet gum 5

6 Test Plant Trap Traps contain two lures: a floral scent, and the female sex pheromone Trap placement was evaluated in 24 home landscapes Traps often increase troubles with Japanese beetles!! Japanese beetle adult control Acelepryn (4 weeks residual) Pyrethroids Onyx (4 weeks) Talstar (2 3 wks) Scimitar Tempo Sevin (1 2 weeks residual) Systemics # 3: Scale Insects Armored Scales have a detachable, shell like cover made from shed skins and waxy secretions Armored Scales Soft Scales Obscure scale on oak an armored scale Covers flipped to expose insects Armored scales encrust branches or leaves; cause dieback and death of plant 6

7 Some common armored scales Pine Needle Scale Euonymus Scale Obscure scale Oystershell scale Pine needle scale Euonymus scale Soft Scales Cottony maple scale Soft scale damage: Dieback from Euonymus Scale Magnolia scale Soft Scales Calico scale Sticky honeydew Sooty mold Crown thinning, dieback Crawler Hatch Scale Insect Control: Spring/Summer Monitor for crawler hatch Pyrethroids (Talstar, Scimitar, Tempo) effective if properly timed Timing Scale Crawler Hatch by Plant Bloom: Oystershell scale coincides with full bloom of Sargent crabapple Euonymus scale coincides with 50% bloom of Kousa dogwood 7

8 Systemic Control for Scale Insects (variably effective): Scale Control by Ant Exclusion Ants tend soft scales to get honeydew They defend their livestock from predators When ants were excluded. Predators reduced soft scales by 60 80%! Trunk injection Soil Treatment Sticky band excludes ants Predators gobble up the undefended scales #2 Borers in trees and shrubs Some Borer Prone Woody Plants Moth ( Clearwing ) borers Ash Lilac Flowering peach, cherry and plum Lilac Borer Peachtree and Lesser Peachtree borers White birch Dogwood Recently transplanted or stressed hardwood trees Dogwood borer Banded ash borer Clearwing borer larvae are whitish caterpillars with a brown head Cleawing Borer symptoms Pupal case of clearwing borer moth that has emerged Crown thinning Sawdust like frass expelled from cracks in bark 8

9 Clearwing Borer Treatment Apply preventive bark spray (pyrethroid or Acelepryn) 1 2 weeks after adults emerge Residues intercept newly hatched larvae as they chew through bark Timing Borer Control By Bloom of Indicator Plants: Lilac borer: Common lilac; full bloom Dogwood borer: Oakleaf hydrangea; first bloom Flat headed Borers Adults are metallic colored beetles Larvae flattened Treat main trunk to runoff Tunnels under bark girdle branches and trunk Flat headed borers leave D shaped holes when adult emerges Bronze Birch Borer: Most destructive Insect Pest of White Birch Flatheaded Appletree Borer: Most destructive pest of maple trees in production nurseries Flatheaded appletree borer also attacks many species of stressed landscape trees Crabapples, maples, hawthorn, dogwood, many others are susceptible Flatheaded Appletree Borer: Bark spray with Onyx in May prevents infestation of nursery liners Systemic insecticides are effective against flat headed borers Newly transplanted trees Stressed trees 9

10 Managing wood borers: Minimize tree stress Avoid trunk wounds Plant well adapted cultivars # 1 Emerald Ash Borer Emerald Ash Borer Toledo, Ohio, USA Before (2006) After (2009) Emerald Ash Borer Attacks & kills all sizes and species of ash Emerald Ash Borer Distribution: 2015 Diagnosing Emerald Ash Borer Tunnels under bark Bowling Green State University golf course Ontario, Canada Thinning, dieback starting at top of tree Suckering D shaped holes Systemic Treatments CAN Protect Trees from Emerald Ash Borer! Rule of thumb: Under 30% canopy dieback, tree can be saved Systemic insecticides for Emerald Ash Borer Not Treated Treated Tree can still be saved Too far gone to save 2 3 year s protection 1 year protection 10

11 MOST EFFECTIVE: Injection or Infusion with Tree Age (Emamectin benzoate) Several different delivery systems are available Other systemic insecticide delivery techniques for emerald ash borer control Soil drench Soil injection Lower trunk spray You You can access EntFacts through the University of Kentucky Entomology web site Insects Turf & Landscape Entomology 11