Good time of year for brush control on prairies

Early March is generally a good time to control brush on a prairie. The snow is generally gone, and the prairie has not been burned yet, so the stems of the woody plants are alive and will translocate herbicide to the roots. Yesterday (March 12, 2017) was especially good because Daylight Savings Time had started, so the afternoon was long.

Black Earth Rettenmund Prairie State Natural Area is a high quality prairie remnant that has been intensively managed for over 30 years, first by the Nature Conservancy (TNC) and now by the Prairie Enthusiasts (TPE). However, despite its high quality, it still suffers from the legacy of woody encroachment that had occurred before TNC acquired it. Particular problem plants have been honeysuckle, sumac, gray dogwood, and bittersweet.

BE Prairie management units are burned two out of each three years. During the third year, brush control is carried out in the unit that has not been burned. The logic here is that woody stems in burned units are killed by fire and hence do not translocate herbicide to the roots. They will get their chance to be killed on a different year! (Cutting and treating dead stems is a waste of time and herbicide. The roots of these top-killed plants are still alive and will resprout during the next growing season.)

Woody plant control with the small brush that we deal with at BE involves a lot of stoop labor. Each stem is hand-cut (clippers) and immediately treated with 20% Garlon 4 in bark oil. A red dye is added to the herbicide in order to keep track of treated stems. Because the small stems are hard to find once cut, it is essential that the same person who cuts the stem treats immediately with herbicide. Thus, this is a two-fisted job.

A three-hour volunteer work party with a 15-minute break in the middle is ideal. You can get a lot of brush killed in 3 hours and it isn't long enough to get bored.

Woody vines being cut and treated on the east side of the North Unit. Five or six years ago, this area had an extensive sumac clone. The shade from the sumac suppressed the prairie grasses, and encouraged the growth of other woody vegetation. Now prairie bunchgrass such as little bluestem is moving in as the woodies are being controlled. Photo by Kathie Brock