Updated spore detection results from the Ergot Alert spore trap network are below. Spores were only detected in the Lower Columbia Basin of Washington State. However, active ergot infections (honeydew and sclerotia) have been observed in at least one commercial Kentucky bluegrass seed production field near Madras.

Updated spore detection results from the Ergot Alert spore trap network are below. Similar to last week, spores were detected in Central Oregon (COAREC) and the Lower Columbia Basin of Washington State (Pasco North and Eltopia East). Spores were also detected in the Grande Ronde Valley (Site 3).

This season we have 17 spore traps deployed in grass seed fields, including 6 in central Oregon, 3 in the Grande Ronde Valley, and 8 in the lower Columbia Basin of Washington State.

So far, spores have been detected in central Oregon (Madras area) and the lower Columbia Basin of Washington State (near Pasco).

A predictive model for ergot ascospores was developed for the Lower Columbia Basin of Oregon that uses accumulated degree-days (beginning January 1, with a base temperature of 50°F and upper threshold temperature of 77°F) to forecast when ascospores are likely to be present.

According to the model, most ascospores are produced in the Lower Columbia Basin when accumulated degree-days are between 414 and 727. Based on this model, the degree-day threshold was reached on May 19, 2023 in Hermiston, OR (accumulated degree days = 428).

In 2022, the degree-day threshold was met on May 27.