IPM for Master Gardeners. Mary Louise Flint, Ph.D. Extension Entomologist Emerita Department of Entomology University of California, Davis

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1 IPM for Master Gardeners Mary Louise Flint, Ph.D. Extension Entomologist Emerita Department of Entomology University of California, Davis

2 What is IPM? Ecosystem-based strategy Focuses on long-term prevention of pests or their damage Requires identification of pests & regular monitoring of the ecosystem Uses a combination of complimentary, environmentally-sound techniques

3 The landscape ecosystem Physical environment: soil, air, weather, shade, sun, water Plant variety Herbivores Carnivores Human activity What factors favor what pests?

4 What are pests? Organisms that are annoying us or damaging our plants or Very personal: Tree squirrels? Scotch broom? Eucalyptus? Spiders? Earwigs? structures Level of pests: a few aphids do little damage to trees and shrubs. Do they need to be controlled? Aesthetic threshold versus economic thresholds

5 Plant damage in the landscape can have many causes Living Pests insects, rodents, disease-causing microbes Snails and slugs Nonliving Abiotic factors Over- or under-watering Nutrient deficiencies Mineral toxicities Fertilizer damage Herbicide damage Mechanical injury Leaf curling due to aphids Leaf curling due to 2,4-D 5

6 Look-alike damage from different causes Fertilizer burn Damage due to fungal disease--pythium blight Herbicide (glyphosate) damage Maintenance Gardener Exam Prep 6

7 The first step in IPM is to accurately identify problems Diagnostic tables in UCIPM books http//: UC Cooperative Extension offices: Advisors in your office or on campuses Agricultural Commissioner s offices/cdfa

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24 Other useful UC IPM web features Natural enemies gallery Weed photo gallery Online training courses

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26 Other Resources from UC IPM Quick Tip pest cards Touch-screen Kiosk Biological Control presentation Posters

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29 What is Integrated Pest Management (IPM)? Ecological approach know pest biology and identification Focuses on preventing problems. Combines several different types of management methods Good cultural practices cultural Biological control Mechanical or physical control Pesticides used only if necessary, as a last resort. Uses least toxic pesticides Protects people and the environment biological mechanical

30 Old pest control paradigm

31 IPM paradigm: Understand why your home/landscape environment favors pests & fix it For ant info & videos go to:

32 Prevention: Choose pest resistant or pest tolerant plants Crape myrtle varieties resistant to powdery mildew Fuchsia varieties resistant to fuchsia gall mite Native plants such as ceanothus

33 Cultural controls (mostly good gardening practices that prevent problems) Site selection Sanitation Habitat modification Water management Fertilizing

34 Good cultural practices prevent lawn pest problems RECOMMENDATIONS FOR MOWING GRASSES TURF SPECIES 1 SET MOWER TO (inches) MOW WHEN TURF REACHES (inches) Annual ryegrass Perennial ryegrass Fertilize properly Tall fescue Colonial bentgrass Rough bluegrass Bermudagrass (for hybrids) (for hybrids) Zoysiagrass For help in identifying your turf grass species, see the UC Guide to Healthy Lawns at the UC IPM Web site, Irrigate properly Mow at proper height

35 Cultural Practices: If you prune, do it right Bad pruning leads to pest problems. branch bark ridge branch collar Removing a branch Use drop crotch pruning instead of topping. Topped tree Flatheaded borer larva Wood decay fungi

36 Physical/Mechanical Controls Cultivation Mowing Flaming Mulches Solarization Traps Screens Barriers etc

37 What is biological control? Any activity of one species that reduces the adverse effects of another Living natural enemies are the agents of biological control Biological control agents limit numbers of all types of pests: insects and other arthropods, weeds, plant pathogens, nematodes, vertebrates Trichogramma (caterpillar egg parasite) Eustenopus villosus (on starthistle)

38 Main Types of Insect Natural Enemies Predators Parasites Pathogens 38 What is Biological Control?

39 Parasites (parasitoids) Adults lay eggs in host Immatures develop within host Kill host just before pupating Immatures kill only one host

40 Hyposoter exigua: a parasite of many garden caterpillars

41 General Predators Prey on a variety of pests Examples: lacewings, ground beetles, predatory bugs, and spiders Present and helpful, but alone rarely control pests Ground beetleàsoil invertebrates Lacewing larvaàsoft insects Assassin bugàmost any insect 41 What is Biological Control? 41

42 Predatory Bugs (Heteroptera) (Nymph) Minute pirate bug (Adult) (Nymph) Bigeyed bug (Adult) (Nymph) Assassin 42 bug (Adult) Minute pirate bugs (Anthocoridae) prey: aphids, mealybugs, mites, psyllids, small caterpillars, scales, thrips, and whiteflies Bigeyed bugs (Geocorinae) prey: other bugs, flea beetles, small caterpillars, and mites Assassin bugs (Reduviidae) stalk: caterpillars, leafhoppers, various small to medium, mobile insects What is Biological Control?

43 Lady Beetles (Coccinellidae) Adult Eggs Larva Pupa The most effective predators specialize on certain prey Convergent lady beetles mostly eat aphids 43 What is Biological Control?

44 Lady Beetles Aphid Specialists Usually are orangish species California lady beetle Sevenspotted lady beetle Twospotted lady beetle Western blood-red lady beetle 44 What is Biological Control?

45 Lady Beetles Specialized Predators Mealybug destroyeràmealybugs Spider mite destroyeràmites Twicestabbedàscales Vedaliaàcottony cushion scale 45 What is Biological Control?

46 Ways of using Biological Control Agents Classical: import exotic species Augmentation: purchase and release Conservation & enhancement: protect native natural enemies

47 Ash Whitefly causes severe damage in the early 1990 s

48 Ash whitefly natural enemies, Encarsia inaron and Clitostethus arcuatus

49 Enhancing natural biological control Provide water, nectar, shelter or alternative food sources Control ants Avoid using pesticides that kill natural enemies*** ***most important!

50 Choose insecticides that are least toxic to natural enemies Less toxic Bt Bacillus thuringiensis Insecticidal oils Insecticidal soaps Moderately toxic Pyrethrin Spinosad Highly toxic Pyrethroids permethrin, bifenthrin Carbaryl-Sevin Organophosphates malathion, acephate imidacloprid

51 Pesticides in the home landscape Many gardeners have beautiful gardens and never use any pesticides Pesticides range in toxicity. Some have little negative impact. Others are quite toxic. We do not understand all the potential impacts of pesticides. Safe pesticides have later been discovered to have serious impacts. Pesticide questions are some of the hardest for Master Gardeners. Rely on written University of California publications for suggestions.

52 Summary: IPM strategy Less risk to health and the environment Emphasis on prevention Fewer pest problems Remember these steps: 1. Correctly identify the pest and determine if it is a problem. 2. Think about the ecosystem! 3. Identify conditions that favor the pest and change them if possible (prevention). 4. Integrate least toxic control methods.

53 IPM for slugs & snails Recognize habitat that favors slugs and snails Remove shelter, consider drip irrigation Choose snail proof plants Handpicking! Traps: boards or beer Copper bands Baits: iron phosphate, least toxic; metaldehyde, more toxic

54 Copper barriers Raised boards to trap snails

55 IPM for Aphids Damage is honeydew--aesthetic. Know they don t kill trees. Prevention: choose plants without aphid problems. Prevention: favored by lush vegetation (fertilizer/pruning) Natural enemies often abundant. Don t kill with insecticides! Manage ants. Hose them off/ prune them out Less toxic insecticides: oils/soaps The systemic neonicotinoid imidacloprid is effective but toxic to bees and beneficials. Rarely needed.