These keys include only the damaging stages of the more common pests in each crop. Insect pests not mentioned in these keys do periodically occur. If you cannot identify your pest or if you question your identification, refer the insect to your state's cooperative extension service or other local experts.

Insects included in the keys do not always cause economic crop losses. Factors such as numbers of insects, stage of insect growth, stage of plant growth, and extent of and potential for damage need to be considered before you decide on pest staus and make control decisions. For specific control recommendations, refer to the Pacific Northwest Insect Control Handbook for the current year.

Alfalfa Caterpillar Colias eurytheme Boisduval
Alfalfa Looper Autographa californica (Speyer)
Alfalfa Seed Chalcid Bruchophagus roddi (Gussakovsky)
Alfalfa Weevil Hypera postica (Gyllenhal)
Army Cutworm Euxoa auxiliaris (Grote)
Ashgray Blister Beetle Epicauta fabricii (LeConte)
Barley Thrips Limothrips denticornis (Halliday)
Bean Aphid Aphis fabae Scopoli
Bean Thrips Caliothrips fasciatus (Pergande)
Beet Armyworm Spodoptera exigua (Hübner)
Beet Leafhopper Circulifer tenellus (Baker)
Beet Webworm Loxostege sticticalis (Linnaeus)
Bertha Armyworm Mamestra configurata Walker
Bird Cherry-Oat Aphid Rhopalosiphum padi (Linnaeus)
Black Cutworm/Greasy Cutworm Agrotis ipsilon (Hufnagel)
Blue Alfalfa Aphid Acyrthosiphon kondoi Shinji
Brown Wheat Mite Petrobia latens (Müller)
Cabbage Aphid Brevicoryne brassicae (Linnaeus)
Cabbage Looper Trichoplusia ni (Hübner)
Cabbage Seedpod Weevil Ceutorhynchus assimilis (Paykull)
Celery Looper Syngrapha falcifera (Kirby)
Cereal Leaf Beetle Oulema melanopus (L.)
Clover Leaf Weevil Hypera punctata (Fabricius)
Clover Root Curculio Sitona hispidulus (Fabricius)
Colorado Potato Beetle Leptinotarsa decemlineata (Say)
Corn Earworm Helicoverpa zea (Boddie)
Corn Leaf Aphid Rhopalosiphum maidis (Fitch)
Cowpea Aphid Aphis craccivora Koch
Diamondback Moth Plutella xylostella (Linnaeus)
English Grain Aphid Sitobion avenae (Fabricius)
European Earwig Forficula auricularia Linnaeus
False Celery Leaftier Udea profundalis (Packard)
False Chinch Bugs Nysius spp.
False Wireworms Eleodes spp.
Garden Symphylan Scutigerella immaculata (Newport)
Grasshoppers and Crickets Orthoptera
Green Peach Aphid Myzus persicae (Sulzer)
Greenbug Schizaphis graminum (Rondani)
Hessian Fly Mayetiola destructor (Say)
Intermountain Potato Leafhopper Empoasca filamenta Delong
Leather Jackets/Crane Fly Larvae Tipula spp.
Lygus Bugs Lygus spp.
Mexican Bean Beetle Epilachna varivestis Mulsant
Mint Aphid Ovatus crataegarius (Walker)
Mint Flea Beetle Longitarsus waterhousei (Kutschera)
Mint Root Borer Fumibotys fumalis (Guenée)
Mint Stem Borer Pseudobaris nigrina (Say)
Nuttall Blister Beetle Lytta nuttalli (Say)
Pea Aphid Acyrthosiphon pisum (Harris)
Pea Leaf Weevil Sitona lineatus (Linnaeus)
Pea Weevil Bruchus pisorum (Linnaeus)
Potato Aphid Macrosiphum euphorbiae (Thomas)
Punctured Blister Beetle Epicauta puncticollis Mann.
Redbacked Cutworm Euxoa ochrogaster (Guenée)
Rose Grass Aphid Metopolophium dirhodum (Walker)
Russian Wheat Aphid Diuraphis noxia (Mordvilko)
Saltmarsh Caterpillar Estigmene acrea (Drury)
Seedcorn Beetle Stenolophus lecontei (Chaudoir)
Seedcorn Maggot Delia platura (Meigen)
Spinach Leafminer Pegomya hyoscyami (Panzer)
Spotted Alfalfa Aphid Therioaphis maculata (Buckton)
Spotted Blister Beetle Epicauta maculata (Say)
Spotted Cutworm Xestia spp.
Stinkbugs Various species
Strawberry Root Weevil Otiorhynchus ovatus (Linnaeus)
Sugarbeet Crown Borer Hulstia undulatella (Clemens)
Sugarbeet Root Aphid Pemphigus populivenae Fitch
Sugarbeet Root Maggot Tetanops myopaeformis (Röder)
Sugarbeet Wireworm Limonius californicus (Mannerheim)
Tuber Flea Beetle Epitrix tuberis Gentner
Turnip Aphid Hyadaphis erysimi (Kaltenbach)
Twospotted Spider Mite Tetranychus urticae Koch
Variegated Cutworm Peridroma saucia (Hübner)
Western Bean Cutworm Richia albicosta (Smith)
Western Corn Rootworm Diabrotica virgifera virgifera LeConte
Western Flower Thrips Frankliniella occidentalis (Pergande)
Western Potato Flea Beetle Epitrix subcrinita LeConte
Western Yellowstriped Armyworm Spodoptera praefica (Grote)
Wheat Curl Mite Aceria tosichella Keifer
Wheat Sawflies Pachynematus spp.
Wheat Stem Maggots Meromyza spp.
White Grub Polyphylla decemlineata (Say)
Zebra Caterpillar Melanchra picta (Harris)