Jul 26, 2016
Late blight spreads in Columbia Basin

Washington State University (WSU) Extension has released a special issue of Potato Pest Alert regarding the spread of late blight to more fields in the Columbia Basin.

Dennis Johnson, WSU professor and Extension plant pathologist, reported the following information in the alert.

Late blight has spread and is extensively present in fields near Burbank, northeast of Pasco, north of Pasco, and north to Eltopia. The strain of the late blight pathogen in the Basin this year is US8, which is resistant to metalaxyl. A serious storage problem, due to tuber infection is potentially ahead for this fall. Monitor fields thoroughly for late blight so you know what you are up against. Fields with late blight should be on a 5 day application schedule. Fields adjacent to infected fields should be on a 5 to 7 day application schedule. All sprinkler irrigated fields in the Columbia Basin should be on at least a 7 to 10 day application schedule. Water needs for many potato crops at this time are decreasing so do not over water. All fields, including rill irrigated fields in the Columbia Basin should be treated with a fungicide before any rainfall. Monitor fields for late blight and watch the weather forecasts for rain.

A recent Potato Progress article, Fungicide Application for Management of Potato Late Blight in the Columbia Basin by Johnson, Philip B. Hamm and Jeffrey S. Miller, has detailed information to help manage the disease.

Contact Dennis Johnson at 509-335-3753 or [email protected] to report, confirm, or make a late blight diagnosis. The hotline number is 1-800-984-7400.

75 Applewood Dr. Ste. A
P.O. Box 128
Sparta, MI 49345


Get one year of Spudman in both print and digital editions for FREE. Preview our digital edition »

Interested in reading the print edition of Spudman?

Subscribe Today »

website development by deyo designs