Adam Osterholzer: adam.osterholzer@colostate.edu, 970-222-9568
Dr. Punya Nachappa: Punya.Nachappa@colostate.edu, 785-383-4873
Visit our website at: https://www.csuwheatentomology.com/.
State-Wide Aphid and Mite Survey
While our program primarily focuses on wheat stem sawfly research, we received numerous reports of mite and aphid outbreaks across Colorado in 2025. Aphid infestations were observed at several locations during the CSU Wheat Field Days (Figure 1). This trend has continued into 2026, with wheat curl mites recently reported in Otis, CO, by Sally Jones-Diamond (CSU Crops Testing).
To better understand these pest outbreaks, our team will initiate weekly statewide sampling beginning in April. Growers will be notified of outbreaks as quickly as possible, and pest populations will be monitored throughout the growing season.
In response to unseasonably warm winter conditions, we also conducted a preliminary survey in January to assess pest presence on volunteer wheat and overwintering wheat. Surveys were conducted at four locations: Yuma, Burlington, New Raymer, and the ARDEC research station in Fort Collins. At each site, samples were collected from transects within CSU Crops Testing fields by harvesting whole plants for inspection. The results of this survey are summarized in Figure 2. Although current pest populations are low, these pests reproduce rapidly, and populations can increase quickly to outbreak levels.
Figure 2: Map depicting pest species found on wheat during the Jan. 2026 survey.
We detected triticum mosaic virus (TriMV) in Yuma, Otis, Burlington, New Raymer, and Fort Collins while wheat streak mosaic virus (WSMV) was found in Otis, Burlington, and New Raymer.
Our findings in the spring will be posted bi-weekly by Colorado Wheat: News | Colorado Wheat. Past newsletters from our program are also archived on the CSU Wheat Entomology website: Extension. We have a full report on CO aphid species in our June 23, 2025 newsletter.
“Identify Cereal Pests” App Now Available for Colorado Growers!
Dr. Marek Boroweic, Director of the C. P. Gillette Museum, developed an app to identify cereal pests.
Identify Cereal Pests uses AI trained on real field images to help growers, crop advisers, and researchers quickly identify major cereal pests right from your phone or browser. Available free for Android, iPhone, and online, the app works in Colorado as well as the Inland Northwest. Every confirmed identification contributes anonymously to a research map, helping improve pest monitoring and integrated management across the region.
Join the growing user community today: download the app, try it in your fields, and help strengthen this resource for all wheat producers.
Acknowledgements: This research is supported by funds from Colorado Wheat Administrative Committee.