Western Colorado Insects

Welcome to the Colorado State University Extension Western Colorado Entomology web site. This site was created and is maintained by Tri River Area Extension Entomology & Agronomy, and is dedicated to presenting factual information on the insects and insect related issues affecting western Colorado.

Entomology Alerts!

Sipha maydis

(Hedgehog Grain Aphid)

in Colorado

Sipha maydis

Spotted Wing Drosophila in

Western Colorado!

Spotted Wing Drosophila (Drosophila suzukii), was confirmed from  Mesa County raspberries in early October 2014. This exotic pest of small fruits, stone fruits, and other soft fleshed fruits has been present on the front range near Ft. Collins since 2012.This is the first confirmed capture in western Colorado. SWD was first found in the US in 2008 and has since spread to many states and northward into Canada.  For more information visit our spotted wing drosophila page.

Photo by Ed Show

Brown Marmorated Stink Bug

Brown marmorated stink bug is present in Colorado in low numbers. Introduction from travlers coming from the Eastern US is common. They have not done any economic crop damage in Western Colorado yet, but we need to keep watching. Be especially aware of large numbers of stink bugs overwintering in homes.
Brown Marmorated Stink Bug ID
Click the images for more info.
Stop Brown Marmorated Stink Bug logo
Brown Marmorated Stink bug map distribution



Intermountain Forage and Legume Production Manual
2nd Edition

Forage Manual Cover
The Intermountain Grass and Legume Forage Production Manual is now available online in PDF format. Individual chapters are available for download.

This page was updated on October 12, 2015

What's New

*Recent Additions*



Colorado Pest



Feb. 17-18, 2016
Montrose Pavillion in Montrose, CO

The Tri River Area Pest Management Workshop is now the Western Colorado Pest Management Workshop.


Past Workshops

2015 WCPMW

2014 TRA PMW

2013 TRA PMW

2012 TRA PMW

2011 TRA PMW


March 14th
Master Gardener Vegetable Garden Presentation Notes


  • The Western Colorado Beekeepers Association has set up a phone line and system to handle honey bee swarm calls. This simplifies the handling of swarm calls and guarantees they are handled safely, professionally and in a timely fashion. 
  • Starting immediately, please route all swarm calls to (970) 589-6316.
  • Check out the Western Colorado Beekeepers Association on Facebook for more information.

Grape Seed Chalcid Poster Thumbnail
Grape Seed Chalcid poster presented at Entomological Society of. America Annual meeting, 13 Nov 2013, Austin TX


Other Useful Links

Arthropods of Colorado
Bugwood-High Plains IPM
Bugwood Main Page
CDMS-Pesticide Labels
Upper Grand Valley Pest Control District

Home Use
Pesticide Labels

Bayer Advanced
Fertilome, Hi-Yield,
Natural Guard, VPG