Beneficial Insects in the Garden: Meet the Good Guys! PJ Liesch UW pliesch@wisc.edu Twitter: @WiBugGuy What are Beneficial Insects? Insects that provide ecosystem services to humans Benefits provided to humans by nature Biological control (i.e., predators & parasites) Decomposition, nutrient recycling Pollination Etc. Useful Resource: 500+ pages Image RICH Biological Control Covers garden/landscape pests AND beneficials Cost (low: ~$35) What is Biological Control The use of biological agents (i.e., non-chemical) to manage pest populations Increasing Populations of Beneficials Some biocontrol organisms are commercially available Results can vary greatly Using mother nature against pests 1) Increase populations of predators/parasites (direct) 2) Increase habitat for beneficials (indirect) Releasing Parasites is fun and something the whole family can do together 1
Increasing Habitat for Beneficials Low Diversity High Diversity Low Diversity High Diversity Herbicide-treated area Conservation Strip (Flowers) Soybeans Wheat Switchgrass Barley Alfalfa Wheat Soybeans Herbicide-treated area Conservation Strip (Switchgrass) Biological Control in the Landscape Predatory insects can be very common in the landscape Beetles True bugs Flies Predators Lacewings and kin Yellowjackets and wasps Spiders Parasites Wasps Flies Roundworms (nematodes) Pathogens Bacteria Fungi Viruses Ground beetles Predators: Beetles Rove beetles Firefly Larva (w/slug) Predators: Lady Beetles Minute Pirate Bug Predators: True Bugs Ambush Bug Multicolored Asian Lady Beetle (Harmonia axyridis) Assassin Bug 2
Predators: Stink Bugs Two-Spotted Stink Bug Spined Soldier Bug in BugFarm Spined Soldier Bug Spined Soldier Bug Predators: Flies Hover Fly (Diptera: Syrphidae) Mantids Two species in WI: Chinese Mantis European Mantis Robber Flies Lacewings Biological Control In Action https://www.youtube.com/watch?v=7jfakox8y3s 3
Bald Faced Hornets Predators: Wasps & Ants Predators: Mites and Spiders Predatory Mites (Acari: Phytoseiidae) Paper Wasp Grass Spider (Above) Wolf Spider (Below) Yellowjacket Ant Orb Weaver Spider Predators: Spiders Parasites (Parasitoids) Usually specialists (only kill one or a few hosts) Can be ecto- or endo- parasites (external vs. internal) Same size or smaller than prey Examples: Wasps Flies Crab Spider w/prey Many species known Parasitic Wasps Tend to attack only a single specific host Some have been purposely released for biocontrol Parasitic Wasps Mummies http://www.youtube.com/watch?v=rltuk-w5gpk 4
Parasitic Wasps Parasites: Flies Tachinid Flies Pyrgotid Fly and May/June Beetle http://www.youtube.com/watch?v=rltuk-w5gpk Parasites: Roundworms (Nematodes) Many species known, some commercially available Can usually infest many different hosts Can be very sensitive to environmental factors UV light, moisture Pathogens Many are highly specific, others can infect many hosts Can be significantly influenced by weather Wet, cool weather more disease Examples: Fungi Bacteria Viruses Pathogens: Fungi Spread through spores Most require high humidity Some commercially available Wet Weather: Diseases 5
Pathogens: Bacteria Some are commercially available Milky spore (Bacillus popilliae) Bacillus thuringiensis Are extremely specific Pathogens: Viruses Viruses exist for many insects, including pests such as armyworms, black cutworm, and gypsy moth Milky Spore Infected Non-Infected Decomposers Dung Beetles (Aphodius sp. and others) Common Decomposers Sexton or Burying Beetle (Nicrophorus sp.) American Carrion Beetle (Nicrophilus americana) Common Decomposers (in Wood) Common Decomposers Blow Fly (Family Calliphoridae) Millipedes Roundheaded Borers (Longhorned Beetles) Flatheaded Borers (Jewel Beetles) 6
Pollinators Pollinators Pollinator: any organism that moves pollen between flowers Honey Bee Bumble Bee Wild Bees Sweat Bee Squash Bee Other Insect Pollinators Moths and Butterflies Wasps Cellophane Bee Beetles Leafcutter Bee All Photos Insect on this Diagnostic slide by Christy LabStewart Flies Meet the Bees: United States: ~4,000 species Wisconsin: ~400 species Honey Bee Bumble Bees UWEX Pollinator Factsheet: G4001 Wild Bees (Sevaral Familes) 7
Bee Biology: What Do Bees Need to Survive? 1. Food Nectar Pollen Ground- Nesting Bee What s Up With Pollinators? Many pollinators face declines due to a variety of factors Habitat loss & fragmentation Agricultural practices Diseases: fungi, viruses, etc. Pesticides Parasites: mites Many other factors 2. Shelter Ground nesters (most bees) Hole/tube nesters (~1/3 of bees) Cavity nesters (bumble bees, feral honey bees) Parasitic Mites How Can YOU Help Pollinators? 1. Use insecticides only when appropriate Explicitly follow allow label directions 2. Make your yard and landscape pollinator friendly Diversity of flowers = diversity of insects Seasonal blooming patterns 3. Provide nesting habitat 4. Educate yourself and get involved! Making the Landscape Pollinator Friendly Diversity of flowers = diversity of insects Ideal situation: 3+ different flowers blooming at any time Pollinator.org Guide: plants to attract bees and other pollinators Go native! Native bees are adapted for native flowers Some commercial flower cultivars ( double flowers ) have little to no nectar or pollen and don t offer resource for bees Tolerate some weeds (i.e., in lawns) Clover, dandelions, etc. can provide nectar/pollen for insects 8
Making the Landscape Pollinator Friendly Provide nesting habitat: many bees nest in hollow tubes Wisconsin Pollinator Protection Plan Inside look at a solitary bee nest Protecting Pollinators in Urban landscapes Available as a free.pdf from Michigan State University Questions? Patrick (PJ) Liesch pliesch@wisc.edu Twitter: @WiBugGuy labs.russell.wisc.edu/insectlab/ 9