When it comes to weeds, first ask why you care. “Is it for esthetics or the bottom line? If for the bottom line, you often can tolerate a lot of weeds,” Tim Schnakenberg, University of Missouri Extension agronomist, said. He and Wendal Rogers, a Natural Resources Conservation Service (NRCS) grassland conservationist pointed to a field of Red River crabgrass and ryegrass studded with weeds: though the pasture wasn’t pretty, the cattle were eating well. Cattle are Rogers’ preferred weed control.
When do you need to spray?
Invasive weeds, sticker-type weeds and woody brush generally require spraying, either spot or broadcast. Rogers also sprays weedy hayfields in late March or early April while the Caucasian bluestem is dormant to remove Johnsongrass seed and other undesirables; he has used a 15 percent to 25 percent Roundup generic in a roto-wipe machine to control Johnsongrass.
To keep spraying affordable when he needs it, Rogers uses a sprayer rebuilt from two junk sprayers, easily picked up at farm sales. With a good tank, good pump and stainless steel tips (about $7 each), you’re in business.
Calibration, though, is critical to effective and safe spraying. While many people know little about calibrating their equipment to meet specifications of applications, NRCS Soil and Water Conservation and Extension staff can help. An Extension sheet on “Pasture Weed & Brush Control” offers clear instructions on how to calibrate. Driving speed, field size, type of weed and herbicide all factor into calibration. To calibrate by ounces, Schnakenberg said, “If you can figure out how much to use on 128th of an acre, that will correspond to gallons per acre.”
For safety, Schnakenberg and Rogers cautioned that herbicides are poisons and treat them accordingly.
Five Herbicide Handling Rules
1. Always read and follow labels
2. Wear rubber boots and gloves and remove hats – leather and cotton will absorb the chemicals
3. Protect your eyes
4. Spray on windless days with no rain expected for 12 to 24 hours
5. Keep livestock off sprayed fields for recommended days
Grazing Management
The Rogers practice 28-day rotational grazing, moving their cattle between 25 acres of Red River crabgrass/ryegrass and other pastures of Caucasian bluestem, white clover and rye. Fencing is primarily electric. Cattle do the fertilizing. Though fire is recommended for warm season grasses like Caucasian, Rogers avoids it because of subdivisions neighboring his farm. Waterpoints are connected to a well with buried or above-ground pipe; freeze-proof pipes and waterers at all stations aren’t necessary, only those for winter grazing, Rogers said.
The Rogers converted to Caucasian bluestem after a 1980 drought wiped out most of their fescue. “We didn’t want to have to supplement,” said Rogers. “Caucasian has done what it was supposed to do for us.”
Reasons to Consider Caucasian
• It’s well balanced between protein and energy and works well with rye, a cool season grass
• It takes only a fraction of rainfall to make it grow
• It’s long-lived – Rogers hasn’t replanted since the original seeding in the early 1980s
• It will take a lot of abuse
• If you fertilize for hay, it takes only about 12 lbs. of phosphorus and 6-7 lbs. of potassium
• Cattle love it both as forage and hay – they get two to four cuttings a year starting in mid-June.
Schnakenberg also urged participants to test for high nitrates in grasses such as Johnsongrass. The prussic acid released after first frosts and at other critical times in the growing season can be fatal to cattle.
