Presentation on theme: "Bug Basics Peter Warren County Extension Director Urban Horticulture Extension Agent Pima County Cooperative Extension University of Arizona."— Presentation transcript:
Bug Basics Peter Warren County Extension Director Urban Horticulture Extension Agent Pima County Cooperative Extension University of Arizona
Overview n The Big Picture n Identification n Diagnosing Plant Damage n Identification Tools n Common & Invasive Pests n Benefits
From “Evolution of the Insects” (Grimaldi & Engel 2005)
Identifying Arthropods n Animals n Segmented body n Exoskeleton n Paired jointed appendages n Bilateral symmetry
Arthropod Groups n Crustacea n Diplopoda n Chilopoda n Symphylans n Xiphosura n Arachnida n Insecta >> Water fleas, shrimps, lobsters, crayfish, crabs, sowbugs (pillbugs) >> Millipedes >> Centipedes >> Symphyla >> Horseshoe Crabs >> spiders, scorpions, harvestmen, mites, ticks >> insects
Insect Classification Kingdom - Animal Phylum - Arthropoda Phylum - Arthropoda Class - Insecta Class - Insecta Order - Hemiptera Order - Hemiptera Family - Pentatomidae Family - Pentatomidae Genus - Nezara Genus - Nezara Species - viridula Species - viridula Author - Linnaeus Author - Linnaeus
Insect Orders n Approximately 31 Orders n Divided primarily on –type of metamorphosis –structure of wings –structure of mouthparts Mantophasmatodea
Insect Development n Metamorphosis –Meta = change –Morph = form n Two types of Metamorphosis –Simple = gradual change –Complete = profound change n Molting n Evolutionarily advanced Orders use complete metamorphosis
Immature versus Adult n Many wormlike n Number of legs varies n Most soft and fleshy n No wings n Most slow moving n Examples –Caterpillars, Maggots, Grubs n Three body segments n Six legs n Most crunchy n Most have wings n Most fast moving n Examples –Butterflies, Flies, Beetles
Key Immature Characteristics n Where are they found? n What are they eating? n Do they have legs? n If so, how many? n Coloration?
Key Adult Characteristics n Exoskeleton –protection –support n Head –antennae –eyes –mouthparts n Thorax –legs –wings n Abdomen –digestion –respiration
Abdomen n Internal organs –For reproduction, digestion, circulation, and respiration n External structures –Cerci: feeler-like appendages –Ovipositor: egg laying device, sometimes modified for defense –Spiracles: openings for respiration
n Herbivorous & predacious bugs and mosquitoes n Mandibles and maxillae are formed into stylets enclosed by the labium n Once the stylets penetrate, a secretion is injected to dissolve tissue –act as a toxin in predacious species –act as anticoagulant for mosquitoes
Diagnosing Plant Damage n Chewed leaves or blossoms n Discolored leaves or blossoms n Distorted leaves, branches, or trunks n Dieback of shoots, twigs, or branches n Products of insects and mites
Types of Insect Injury n Chewing n Piercing sucking n Internal feeders n Subterranean n Egg laying n Nest material n Disease vector >> beetles, caterpillars, grasshoppers, etc. >> aphids, scale, leafhoppers, etc. >> leaf miners, borers, caterpillars, etc. >> wireworms, root maggots, rootworms, etc. >> cicadas, gall insects, etc. >> leaf cutter bees, etc. >> aphids, leafhoppers, bees, beetles, etc.
Effective Diagnosis n Recognition of symptoms –Regular monitoring –Record keeping n Accurate identification –Close examination –Consulting experts as needed n Knowledge of pest life cycle –Identify susceptible life stages –Determine location for management n Distribution of pest population –Are there enough of them to be a problem? –Are they wide spread or spreading?
Landscape CSI n Success depends on early identification and diagnosis n Clues for diagnosis –Problem symptoms »Nuts drop early »Nuts without edible meat –Problem signs »Worm-like critter or frass in shell »Holes in shell –Host preference »Shagbark hickory n Resources for diagnosis –Coworkers –Reference books, internet –Extension Office
Determining Insect Pest Status n First goal: identify to Order level (such as bee, beetle, fly) –antennae, wings, mouthparts –shape, texture, size, color –life stage: egg, larva, pupa, adult n Then use other clues to determine pest status –Host plant –Activity and/or damage »feeding, flying, crawling, etc.
Sources of Information n Publications –Land-grant Universities –OMRI.org –BIRC.org n Community Availability –Survey Local Stores/Nurseries –Cooperative Extension/MGs n Dotcom Resources & Catalogs –Buyer beware –Check for products that have been tested by reputable organizations –Ask for data and references
Components of an IPM Program n Knowledge of Plants and Pests –Potential pests and conditions likely associated n Setting Goals for Protection –Action thresholds and available control options available n Site Maps –Details the physical and environmental features n Monitoring –Weekly checks recommended n Making Control Decisions –Considering the data available n Record Keeping –Date, location, weather, activity n Evaluation
Overview of IPM Options n Host resistance n Biological control n Chemical control n Cultural control n Mechanical control n Do nothing
Host Resistance n Plants naturally evolve resistance to pests n Plant breeding is used to alter the process n Genetic engineering provides a new wrinkle This must be the one with insect resistance!
Biological Control n Predators, parasites or parasitoids, and pathogens n Lower pest densities to innocuous levels and keep them there n Attract beneficial insects by planting flowering nectar & pollen sources n Release beneficial insects into environments where pests exist
Chemical Control n Avicides to control pest birds n Bactericides to destroy bacteria n Fungicides to destroy fungi n Herbicides to kill weeds n Insecticides to destroy insects n Miticides to kill mites n Molluscicides to kill snails and slugs n Nematicides to kill nematodes n Piscicides to control pest fish n Predacides to control vertebrate pests n Rodenticides to destroy rodents
Pesticide Effectiveness n Type –match chemical with problem n Time –use chemical when most effective n Place –use chemical where most effective
Non-target Organisms n Mammals n Birds n Fish n Bees
Least Toxic Insecticides n Bacillus thuringiensis (Bt) for caterpillars, beetles, flies, etc. (making sure you buy the right one) n Insecticidal soap for aphid, mealybug, psyllid, spider mite, and whitefly control n Horticultural oils for sessile (or nearly so) pests such as hemlock wooly adelgid
Cultural Control n The deliberate alteration of the plant production system to reduce pest populations or avoid pest injury to plants n The key to successful IPM n Three basic types –Site selection –Soil preparation –Plant selection
Diversity n Avoid large plantings of one type –less attractive from the start –can slow the spread of pests n Include farmscaping plants if diversity is not realistic n Use native and well adapted species n Use disease and insect resistant varieties
Mechanical and Physical Control n Direct or indirect measures that either destroy pests outright or make the environment unsuitable n Removing pests –by hand, with traps n Preventing access to plants –screens, ditches, row covers n Sanitation –remove shelter, food sources, moisture, attractive odors
Three Cardinal Rules of IPM n Know your ecosystem n Scout regularly n Keep good records
Invasive Insects n Mostly accidental introductions –Notable exceptions include gypsy moth –Humans are excellent vectors n Success –No natural enemies –Similar food plants –Similar climate n Management –Difficult to eradicate –Efforts to slow the spread –Always bet on the bug brown marmorated stink bug