Steph Bonson
for the Burns Times-Herald

Well, as you probably noticed, we have had a banner year for the perennial weed, White top!  It is everywhere, in the fields, rangeland, and even in cracks in the sidewalk in town. If you are not sure what White top looks like, here are some distinguishing features. It is a deep-rooted plant, which can be up to two or three feet tall. It has blue-green, lance-shaped leaves. Of course, the most obvious feature is the numerous, small, four-petaled white flowers, which form a flat-topped appearance.

One of the best times to spray White top is when the flowers are in full bloom. This time has pretty much passed, but don’t lose heart, it is also a good time to spray in the fall regrowth stage. A mixture of 1 ounce of Chlorsulfuron (Telar) and 1 quart 2, 4-D/acre (if you’re handgunning, this translates to: .5 ounce Telar plus .64 ounces 2, 4-D/ gallon of water) is recommended.

Hand-pulling is only minimally effective because the plant reproduces from root segments, as well as seeds. New plants can emerge from small root segments left in the ground. Mowing can reduce seed production if done before the plant has gone to seed. Mowing will not kill the plants; however mowing can enable better targeting of herbicides.  It is also a good practice to remove all weed seeds from clothing, shoes, pets, camping gear and tire treads.

If you have questions about White top or other weeds, feel free to give us a call at Harney County Weed Control, 541-573-8397/8385. Or visit us at the Harney County web site, or on facebook at Harney County Cooperative Weed Management Area. We also have cheat sheets for spraying calculation. We will be glad to help.