MSU Extension Pesticide Education Ornamental Pest Management (Category 3B) Biology and Management of Pests Chapter 6

A “stab in the dark” approach to pest management is seldom effective. It may injure desirable organisms.

MSU Extension Pesticide Education Effective Pest Management F Requires... –Knowledge of pest life cycle –Feeding habits –Hosts –Environmental interaction –Reproductive behavior

MSU Extension Pesticide Education Diseases of Ornamentals F Disease = disturbance of normal plant function. –Noninfectious (abiotic) EnvironmentalEnvironmental Cultural practicesCultural practices –Infectious FungiFungi BacteriaBacteria VirusVirus

Apple Scab Life Cycle infected leaves fall Winter fungus overwinters on fallen leaves Spring spores blown to new leaves leaf to leaf infection Summer

MSU Extension Pesticide Education Plant Diseases F Grouped according to: –Causal agent –Symptoms they produce

MSU Extension Pesticide Education Disease Symptoms F Leaf spots F Scab F Rusts F Powdery mildew F Mosaics F Chlorosis F Scorch F Witches’ broom

MSU Extension Pesticide Education Disease Symptoms F Anthracnose F Cankers F Blights F Wilts F Decline F Galls F Rots

MSU Extension Pesticide Education Scab

MSU Extension Pesticide Education Rust

MSU Extension Pesticide Education Cedar-Hawthorne Rust Cedar-Apple Rust

MSU Extension Pesticide Education Powdery Mildew

MSU Extension Pesticide Education Mosaic

MSU Extension Pesticide Education Chlorosis: Oak and Maple

MSU Extension Pesticide Education Witch’s broom caused by Anthracnose

MSU Extension Pesticide Education Anthracnose on foliage and in woody tissue.

MSU Extension Pesticide Education Fireblight on Mountain Ash

MSU Extension Pesticide Education Root rot problem on Rhododendron

MSU Extension Pesticide Education Common symptom of tree decline.

MSU Extension Pesticide Education

MSU Extension Pesticide Education Host Susceptibility F Plant selection F Plant parts F Vigor

Weather Conditions F Humidity F Rainfall F Temperature

Microclimate F Shade F Wind F Salt F Location F Crowding

MSU Extension Pesticide Education Infectious Disease Management F Resistance –Superior species, cultivars, varieties F Avoidance –Appropriate site conditions F Elimination –Sanitation; some fungicides F Protection –Most fungicides

MSU Extension Pesticide Education Although cultural and environmental disorders are most common, “bugs” are perceived as the likely cause of a problem.

Insects of Ornamentals F Capable of wide variety of injury F May go through several life stages F Activity and injury often seasonal F Classified by physical characteristics F Classified by behavior

MSU Extension Pesticide Education Insect Classification by Feeding Behavior F Piercing - sucking F Leaf-chewing F Tent and case-making F Gall-forming F Root-feeding F Boring

MSU Extension Pesticide Education Piercing-sucking Insects F Aphids F Leafhoppers F Plant bugs F Mealybugs F Thrips

MSU Extension Pesticide Education Piercing-sucking Insects Aphids

MSU Extension Pesticide Education Piercing-sucking Insects Pine Needle Scale

MSU Extension Pesticide Education Piercing-sucking Insects Magnolia Scale

MSU Extension Pesticide Education Piercing-sucking Insects Sooty mold grows on the honey dew secreted from piercing-sucking insects.

MSU Extension Pesticide Education Piercing-sucking Insects Plant Bug

MSU Extension Pesticide Education Piercing-sucking Insects Leaf Hopper Injury

MSU Extension Pesticide Education Leaf-Chewing Insects F Caterpillars F Sawflies F Leafminers F Leaf beetles F Weevils

MSU Extension Pesticide Education Leaf-Chewing Insects Eastern Tent Caterpillar

MSU Extension Pesticide Education Leaf-Chewing Insects Pine Sawfly

MSU Extension Pesticide Education Leaf-Chewing Insects Oak leaf miner (moth) Birch Leaf Miner (sawfly)

MSU Extension Pesticide Education Leaf-Chewing Insects Japanese Beetle

MSU Extension Pesticide Education Leaf-Chewing Insects Black Vine Weevil: Adult, pupae, larvae (legless), and foliar damage

MSU Extension Pesticide Education Leaf-Chewing Insects White grub of Japanese beetle: a root feeder.

MSU Extension Pesticide Education Maple Bladder Gall

MSU Extension Pesticide Education Cooley Spruce Gall

MSU Extension Pesticide Education Bronze Birch Borer exit hole

MSU Extension Pesticide Education Insect Management F Protection for insects: –Pupal stage –Waxy coating –Galls –Bark –Leaf tissue –Soil

Insect Management- Consider: F Susceptible life stage F Damaging stage F Period of feeding F Weather conditions F Number of generations F Host tolerance F Natural enemies

MSU Extension Pesticide Education Non-Chemical Insect Controls F Improve plant vigor F Encourage natural enemies F Select plants with resistance F Modify the environment

Natural enemies of insects can provide safe, long lasting “control.” Pesticides can upset this balance and increase some problems.

MSU Extension Pesticide Education Insecticides F Avoid problems: –Monitor plants for insects –Protect beneficials –Time for appropriate life stage –Avoid preventative pesticide treatments –Use the least toxic materials

MSU Extension Pesticide Education Mites F Not insects (eight legs) F Rasp leaf cells and suck contents –Causes bronzing F Some form webs or galls F Weather dependent - prefer hot spots F Rapid population build up F Paper test

MSU Extension Pesticide Education Spider mites Webbing Bronzing

MSU Extension Pesticide Education Nematodes F Microscopic worms F Commonly attack roots or vascular system F Symptoms: wilting, stunting, dieback F Resistance F Few nematicides F Detection - MSU Lab

MSU Extension Pesticide Education Snails and slugs leave irregular holes in foliage where they feed and slime trails where they’ve traveled.

Snails and Slugs F Soft bodied animals F Weather and site dependent F Slime trail F Not controlled by insecticides F Sanitation and traps

Vertebrates F Cause damage by: –Chewing –Rubbing –Drilling

MSU Extension Pesticide Education Squirrel damage Rabbit damage

Wildlife control in urban areas can be difficult. Consider using barriers, repellants and pest removal tactics. Excluding mice, moles and chipmunks, trapping vertebrates is regulated by MDNR.

THEEND Prepared by : Greg Patchan, Julie Stachecki, and Kay Sicheneder MSU Extension Pesticide Education Program