Update spore counts are available for the Lower Columbia Basin (OR and WA) and central Oregon. While spore detection declined at the Lower Columbia Basin research site in OR, increased inoculum levels were observed across the river at our Lower Columbia Basin research site in WA and at COAREC in central Oregon:

Spores were detected on all days during the first week of June, albeit at lower numbers than observed during the latter half of May:

Both honeydew and sclerotia have been observed on Kentucky bluegrass and perennial ryegrass plots located at the Hermiston Agricultural Research and Extension Center:

Protective fungicides should be applied at the onset of anthesis to protect unfertilized flowers from infection, and cultivars with prolonged flowering periods may require more than one application.

Please refer to the PNW Plant Disease Management Handbook for more information on fungicide options for ergot (https://pnwhandbooks.org/plantdisease/host-disease/grass-seed-ergot), or contact Jeremiah Dung using the “Leave a reply” link above.

Spore production was steady during the final week of May, with over twice as many spores captured (1,503 spores/week) compared to the previous four weeks (641 spores total):

Honeydew and sclerotia have been observed in research plots located at the Hermiston Agricultural Research and Extension Center.

Many Kentucky bluegrass seed fields in the area are mature or nearing maturity. Field scouting for honeydew at this time can help identify infected fields which may present difficulties during swathing, harvesting, and seed cleaning operations.

Updated spore counts are available for the Lower Columbia Basin of Oregon:

The final week of May began with extremely large spore counts (>40,000 spores/day), but spore production tapered off as the month wound down. However, the number of spores captured per day was still relatively high (>600 spores/day) compared to other locations.

Protective fungicides should be applied at the onset of anthesis to protect unfertilized flowers from infection, and cultivars with prolonged flowering periods may require more than one application.

Please refer to the PNW Plant Disease Management Handbook for more information on fungicide options for ergot (https://pnwhandbooks.org/plantdisease/host-disease/grass-seed-ergot), or contact Jeremiah Dung using the “Leave a reply” link above.