Overview
Colorado is home to many species of insects ranging from beneficial to harmful. Extension has resources to help identify insects and appropriate control measures. Topics in this section include: Exotic (Non-established in Colorado), Field & Forage Crop, Fruit, Flower & Vegetable Garden, General Insect Control, General Interest Subjects/Miscellaneous, Household, Stinging & Biting, Trees & Shrubs and Turfgrass insects.
- Emerald Ash Borer Resources
Resources to help assess your trees, FAQs, identification and other helpful information regarding this new pest. - Pest Alerts
Pests and diseases affect animals, plants, and humans. Some active pests are highlighted which include: Elm Flea Weevil, Walnut Twig Beetle and Thousand Cankers Disease of Black Walnut, Pheromone Traps are up to monitor Bugs and Russian wheat aphids and alfalfa weevil. - Insect Calendars
Monthly insect problems throughout the state including: Arapahoe, Douglas & Elbert Counties; Denver, Adams & Boulder Counties; Eastern Plains Counties; High Country Counties; Jefferson & Park Counties; Pueblo & Fremont Counties; Tri-River Counties; and Weld, Larimer & Cheyenne Counties
Publications
CSU Extension has several publications related to insects. Topics in this section include:
- Field & Forage Crops
- Fruit, Flower & Vegetable Garden
- General Interest Subjects/Miscellaneous
- Greenhouse and Houseplants
- Household
- Integrated Pest Management Educational Materials
- Stinging & Biting
- Trees & Shrubs
- Turfgrass
Field & Forage Crops
- Alfalfa Weevil (5/11)
- Aphids in Alfalfa (5/11)
- Aphids in Small Grains (4/16)
- Armyworms (8/10)
- Black Grass Bugs (8/13)
- Blister Beetles in Forage Crops (8/10)
- Bt Corn: Health and the Environment (9/13)
- Caterpillars on Field Crops: I (9/14)
- Caterpillars on Field Crops: II (9/14)
- Caterpillars on Field Crops: III (9/14)
- Caterpillars in Small Grains (8/10)
- False Chinch Bugs (6/13)
- Grasshoppers in Field Crops (10/14)
- Insect Damage to Farm-Stored Grain (8/10)
- Managing Corn Pests with Bt Corn (12/14)
- Mites in Wheat (12/14)
- Native Bee Watch – A Colorado Citizen Science Field Guide (3/18)
- Spider Mites in Corn (12/14)
- Spotted Lanternfly, Lycorma delicatula (8/20)
- Stalk Borers in Colorado Field Corn (2/08)
- Sunflower Stem Weevil Management (8/10)
- Western Bean Cutworm: Characteristics and Management in Corn and Dry Beans (10/14)
- Western Corn Rootworm (9/13)
- Wheat Stem Sawfly: A New Pest of Colorado Wheat (10/14)
Go to top of this page.
Fruit, Flower & Vegetable Garden
- A Beginners Field Guide to Identifying Bees
- Attracting Butterflies to the Garden (6/13)
- Attracting Native Bees to Your Landscape (11/17)
- Beneficial Insects and Other Arthropods (2/09)
- Codling Moth: Control in Home Plantings (6/13)
- Creating Pollinator Habitat (1/18)
- European Earwigs (7/14)
- European Paper Wasp (6/13)
- False Chinch Bugs (6/13)
- Flea Beetles (1/19)
- Fungus Gnats as Houseplant and Indoor Pests (4/09)
- Grape Leafhopper (Erythroneura spp.) (12/19)
- Grasshopper Control in Gardens & Small Acreages (1/13)
- Greenhouse Whitefly (6/13)
- Harlequin Bug (1/18)
- Hornworms and Hummingbird Moths (7/14)
- Insect Control: Horticultural Oils (12/13)
- Insect Control: Soaps and Detergents (3/08)
- Integrated Hive Management for Colorado Beekeepers (7/20)
- Japanese Beetle (3/18)
- Lady Beetles (7/14)
- Leafcutter Bees (12/12)
- Mantids of Colorado (1/19)
- Native Bee Watch – A Colorado Citizen Science Field Guide (3/18)
- Peach Tree Borer (7/14)
- Pigeon Tremex Horntail and the Giant Ichneumon Wasp (7/13)
- Potato or Tomato Psyllids (1/19)
- Slugs (1/13)
- Snailcase Bagworm (7/14)
- Spider Mites (7/14)
- Spotted-wing Drosophila: Management in Home Plantings (3/17)
- Springtails (12/12)
- Squash Bug: Management in Home Gardens (1/13)
- Tobacco (Geranium) Budworm (1/20)
- Weird Worms: Horsehair Worm and the Grasshopper Nematode (6/13)
Go to top of this page.
General Interest Subjects/Miscellaneous
- A Beginners Field Guide to Identifying Bees
- Attracting Butterflies to the Garden (6/13)
- Attracting Native Bees to Your Landscape (11/17)
- Beneficial Insects and Other Arthropods (2/09)
- Bt Corn: Health and the Environment (9/13)
- Cicadas (2/19)
- Creating Pollinator Habitat (1/18)
- Insect Control: Horticultural Oils (12/13)
- Insect Control: Soaps and Detergents (3/08)
- Insect Control: Insect Parasitic Nematodes (6/13)
- Integrated Hive Management for Colorado Beekeepers (7/20)
- Lady Beetles (7/14)
- Mantids of Colorado (7/14)
- Native Bee Watch – A Colorado Citizen Science Field Guide (3/18)
- Weird Worms: Horsehair Worm and the Grasshopper Nematode (6/13)
- Windscorpions (Sunspiders) of Colorado (3/17)
Go to top of this page.
Greenhouse and Houseplants
- Houseplants: Managing Houseplant Pests (6/13)
- Brown Soft Scale – A Common Insect Pest of Indoor Plants (1/20)
- Greenhouse Whitefly (6/13)
- Fungus Gnats as Houseplant and Indoor Pests (4/09)
Go to top of this page.
Household
- Ants in the Home (1/17)
- Bat Bugs, Bed Bugs and Relatives (3/11)
- Bed Bug Lookalikes – Bat Bugs and Swallow Bugs in Colorado (4/20)
- Boxelder Bugs (12/14)
- Brown Recluse Spiders in Colorado: Recognition and Spiders of Similar Appearance (12/12)
- Carpenter Ants (8/10)
- Clover and Other Mites of Turfgrass (6/13)
- Cluster Flies and other “Winder Flies” (2/18)
- Cockroaches (6/12)
- Conifer Seed Bugs (7/14)
- Dermestid Beetles (Carpet Beetles) (1/18)
- Elm Leaf Beetles (1/18)
- Elm Seed Bug: A New Nuisance Pest in Colorado Homes (6/18)
- European Earwigs (7/14)
- Feeding Honey Bees in Colorado (7/19)
- Flies in the Home (1/17)
- Fungus Gnats as Houseplant and Indoor Pests (4/09)
- Houseplants: Managing Houseplant Pests (6/13)
- Indian Meal Moth (1/17)
- Insect Pests of Home-Stored Foods (12/08)
- Integrated Hive Management for Colorado Beekeepers (7/20)
- Miller Moths (7/14)
- Miller Moths – Questions and Answers (5/21)
- Millipedes, Centipedes and Sowbugs (12/13)
- Moths in the Home (3/08)
- Root Weevils (1/19)
- Spiders in the Home (9/13)
- Springtails (12/12)
- Termites (12/14)
- Western Widow Spider (1/13)
- Windscorpions (Sunspiders) of Colorado (3/17)
Go to top of this page.
Stinging & Biting
- Conenose Bugs (“Kissing Bugs”) and Insects of Similar Appearance in Colorado (2/20)
- Fleas and Plague (6/13)
- Brown Recluse Spiders in Colorado: Recognition and Spiders of Similar Appearance (12/12)
- Biting Flies (6/13)
- European Paper Wasp (6/13)
- Ticks and tick-borne Diseases in Colorado (2/19)
- Wasps and Bees (12/12)
- Western Widow Spider (1/13)
Go to top of this page.
Trees & Shrubs
- Aphids on Shade Trees (1/19)
- Boxelder Bugs (12/14)
- Brownheaded Ash Sawfly (7/14)
- Cicadas (2/19)
- Conifer Seed Bugs (7/14)
- Cooley Spruce Galls (6/13)
- Douglas-Fir Tussock Moths (1/20)
- Elm Leaf Beetles (1/18)
- Elm Seed Bug: A New Nuisance Pest in Colorado Homes (6/18)
- Emerald Ash Borer: Insecticides Used to Control Emerald Ash Borer on
Residential Shade Trees (5/20) - Insect and Mite Galls (6/13)
- Insect and Mite Pests of Honeylocust (6/13)
- Ips Beetles (6/13)
- Leafcutter Bees (12/12)
- Leafmining Insects (7/14)
- Lilac/Ash Borer: A Common Wood Borer of Colorado’s Street Trees (5/14)
- Mountain Pine Beetle (9/11)
- Oystershell Scale (5/13)
- Peachtree Borer (1/18)
- Pear Slugs (7/14)
- Pigeon Tremex Horntail and the Giant Ichneumon Wasp (7/13)
- Pine Tip Moths (12/08)
- Poplar Twiggall Fly (6/13)
- Recognizing Wood Boring Insects of Ash Trees in Colorado (1/19)
- Root Weevils (5/16)
- Scale Insects Affecting Conifers (6/13)
- Shade Tree Borers (1/19)
- Snailcase Bagworm (7/14)
- Tent-Making Caterpillars (6/13)
- White Pine Weevil (12/12)
- Zimmerman Pine Moth (1/20)
Go to top of this page.
Turfgrass
- Billbugs and White Grubs: Control in Home Lawns (1/19)
- Japanese Beetle (3/18)
- Leafhoppers on Lawns (12/12)
- Insect Parasitic Nematodes (3/08)
- Clover and Other Mites of Turfgrass (6/13)
Go to top of this page.
News
News
Hot Topics
 Wheatstem Sawfly Extension has responded to the building crisis brought on by the wheat stem sawfly pest. Learn more |
 Emerald Ash Borer Resources Resources to help assess your trees, FAQs, identification and other helpful information regarding this new pest. Learn more |
 Japanese Beetle Japanese beetle adults chew flower blossoms and leaves of many commonly grown plants. Learn more |
 Grasshopper Control in Gardens and Small Acreages Grasshoppers are the most difficult insect to control because they are highly mobile. Learn more |
 Leafcutter Bees Leafcutter bees are not aggressive and have a mild sting that is used only when they are handled. Learn more |
Programs
Insect Featured Programs
 High Plains Pest Management Integrated Pest Management Guide for Colorado, Western Nebraska, Wyoming, Montana and Western South Dakota. Learn more here: https://wiki.bugwood.org/HPIPM:Main_Page |
 Western Colorado Entomology Current insect alerts, information and courses for western Colorado. Learn more |
 The Northeast CO Pest Alert Program Monitoring field crop pests in Adams, Arapahoe, Boulder, Kit Carson, Logan, Phillips, Yuma, Sedgwick, Washington and Weld and neighboring counties. Learn more |
Websites
CSU-affiliated sites
- Biting and Stinging Insects: Resources for Handling Public Inquiries
- Colorado Bug Mugs
- Colorado State Forest Service – Common Insects and Diseases
- High Plains Integrated Pest Management – https://wiki.bugwood.org/HPIPM:Main_Page
- Miller Moths – Questions and Answers
- Mystery Bites and Itches – Arthropod and Non-Arthropod Sources in Colorado
- Plant Diagnostic Clinic
- Thousand Cankers Disease/Walnut Twig Beetle
- Western Integrated Pest Management Center
- West Nile Virus Resource List
External Sites
- Busting Bugs: USDA Online Tool to ID Pests
- National Pesticide Information Center
- Rangeland Grasshopper & Mormon Cricket Suppression Program
- University of Nebraska – Lincoln (Insects & Spiders)
