With continued hot, dry weather it is important to remain vigilant for emerging twospotted spider mite problems in field crops. Look for characteristic yellow stippling on leaves and confirm the presence of mites by tapping vegetation over a piece of black construction paper (which works better than white paper, though white will do) and looking for dust that crawls. Increasing mite populations often start on field edges, and edge treatments may work if problems are caught early. But if mites are found beyond the field borders and if conditions are very favorable for mite increase (continued hot, dry weather with low chance of rain), either make your treatment decision for the whole field, or be prepared to scout often and vigilantly and treat quickly when interior populations increase.
Threshold recommendations for spider mites in soybean are summarized in a previous newsletter article:
For thresholds for spider mites in corn we follow recommendations developed by Texas A&M, which can be found at this link: