Research Assistant Authors: Ashley Raffa, Anne Sellman, Johanna Merkel, Zhi Mei Maria Lee, Ella Stankiewicz
Adam Osterholzer: adam.osterholzer@colostate.edu, 970-222-9568
Dr. Punya Nachappa: Punya.Nachappa@colostate.edu, 785-383-4873
Colorado state-wide wheat stem sawfly survey
The CSU Wheat Entomology Program, with the support of Colorado Wheat, conducts an extensive annual state-wide survey for wheat stem sawflies. For over a decade, our program has visited 17 wheat-producing counties throughout the state. Within these counties we collect and dissect 100 wheat stems from several field sites to determine sawfly larval infestation in each site.
Our results this year were notable in that they contrasted sharply with those of last year. As shown in Figure 1, there were fewer instances of high sawfly infestation (which are represented by the yellow regions on the infestation maps). Also of note is sawfly expansion to both southern and western regions. Baca, Boulder, and Larimer counties all went from having no infestation last year to low/moderate infestation this year. The new infestation in Boulder County was particularly notable, going from 0% infestation to 25%. For a county-level infestation summary see Table 1.