Rust in pasture

Asked September 8, 2015, 5:37 PM EDT

Three years ago we planted a pasture mix in a new 3 ac field. This year we took hay off it, then fertilized with 16-16-16 and irrigated it. It grew to 10 to 12 inches because the cows (2 herefords) weren't eating it. We mow around the perimeter and that's where the cows prefer to eat. There is evidence of the tips of grass yellowing. After mowing the pasture there is rust on the mower. Questions: Is the rust harmful to the cows? What caused it? How do we get rid of it?

Benton County Oregon

1 Response

HI. Rust is not harmful per se to the animals. Anmals will eat the grass although depending upon severity, the rust may affect palatability, if really severe, there could possibly be problems from inhalation perhaps, Many grass speices are susceptible to rust, and the varieties within the species have different degrees of susceptibility. Environmental conditions cause the rust to appear, a lot of times in the Fall is when it shows up, There is nothing you can do to get rid of it. If you have more questions you might contact Shelby Filley, Douglas County Extension, at 541-672-4689 or Gene P:irelli, Polk County Extension, at 503-623-8395. Both of these agents have direct experience on the west side of the Cascades.

Mylen Bohle
Area Extension Agronomist
Central Oregon
Crook County Extension Service