Garden Pest ID and Control Valerie Kish 6 April 2019 Hanover Gardening Series

Who Are The Pests? Weeds Wiregrass = Bermuda grass Hairy bittercress www.umd.edu

Who Are The Pests? Insects Squash vine borer: left = adults; right = eggs develop into larva/worm in stem. www.extension.umn.edu

Who Are The Pests? Diseases Powdery mildew on raspberry (Rubus spp.) www.osu.edu Rust on hollyhock www.ag.umass.edu

Integrated Pest Management (IPM) Strategy for keeping pest population at an acceptable level Non-chemical approaches first Pesticides are a last resort Selective control of targeted pest Requires identification of pest

Healthy Unstressed Plants Are Less Susceptible to Pest Effects Healthy plants resist insect damage and plant diseases more than unhealthy plants Healthy soil makes healthy plants Grow plants under optimum conditions (light, moisture, soil pH, nutrient supply, etc) Plants grown under less than optimum conditions are stressed and are susceptible to disease and insect damage (e.g. drought stress)

First Step: Know Your Garden Scout and keep records Know what healthy plants look like Look for evidence of pests (e.g. chewed leaves, eggs, etc.) Black vine weevil notches periphery Assassin bug eggs

How Much Damage Can You Tolerate? Powdery Mildew on Phlox, missouribotanicalgarden.org. Japanese Beetles, extension.umd.edu

Second Step: Is Damage Due to Environment, Insect, Disease? Tomato with herbicide injury www.ncsu.edu Brown rot of peaches hgic.clemson.edu

Third Step: Non-chemical Control Physical/mechanical Cultural Row covers protect plants from egg-laying female insects Crop rotation disrupts pest life cycle

Third step: Non-chemical Control Biological Controls: Beneficial Nematodes Pestid.msu.edu Japanese beetle grub killed by nematodes extension.csu.edu

Non-chemical control Adding biodiversity helps control pests Aim for layers and native plants www.vnps.org Eastern bluebird www.wildfocus.org

Pesticides: A Last Resort All pesticides are toxic; all are dangerous Pesticide Applicator License Training www.npic.orst.edu

Read the Pesticide Label You must follow the label, it is the LAW. Types of pesticides Insecticide (kills insects) Herbicide (kills plants) Fungicides (kills fungi) Miticides (kills mites) Nematocides (kills nematodes) ID the pest and choose least toxic pesticide

Low-Impact Insecticides Microbial (Bt, bacteria) Botanical (Pyrethrum) Bt-infected caterpillar (top) www.wimastergardener.org Chrysanthemum cinerarium, researchgate.net

Synthetic Insecticides More toxic than low-impact May last longer in the environment Sevin marketed as broad-spectrum insecticide Targeting…no! Kills over 100 pests (grubs, spiders, mites, ticks, insects) Selective…no! Penetrates mulch and kills soil insects Rapid breakdown…no! 3 month control…”sit back and watch all those pesky critters die.”

Remember IPM Pyramid

Keep Food Web Intact When Controlling Garden Pests