Growing grass efficiently was the focus of the LSU AgCenter Red River Research Station Beef and Forage Field Day held April 16.
Farmers and ranchers have several herbicide options available for pastures said LSU AgCenter weed scientist Ron Strahan. He showed a plot where several different chemicals were used to treat the broadleaf weed curly dock.
2,4-D is the cheapest option at roughly $3 an acre, Strahan said. A quart of 2,4-D per acre caused damage to clover, but using only a pint per acre would still be effective and cause less clover injury.
Other chemicals, such as Weedmaster, Grazon P+D, Grazon Next and Surmount are options, but they also can injure clover.
Grazon P+D contains 2,4-D plus the chemical picloram and performed best on curly dock. It costs $8 to $10 per acre, but it can damage or kill desirable trees nearby.
The herbicide Pasturegard is effective on woody plants, but it also damages clover.
Strahan demonstrated the “hack-and-squirt” method of killing Chinese tallow trees, using an axe or machete to cut a slash into the tree, followed by an application of Grazon P+D. “It has been 100 percent effective on Chinese tallow.”
Legumes such as cowpeas are difficult to establish in a pasture, but they offer good forage, said LSU AgCenter forage researcher Buddy Pitman. Management is required to get the growth started.
“You can’t just scatter the seed out there and expect it to be a workable product,” Pitman said.
Keeping past soil test results will show any nutrient trends in a pasture’s soil, said LSU AgCenter agronomist Wink Alison.
Urea has become a popular form of nitrogen fertilizer, but it tends to decompose if the application is not followed by rain three to four days later, Alison said.
A nitrogen loss of 20-25 percent is possible, but once the material is in the soil, volatilization is reduced. Urease inhibitors such as Agrotain offer protection against volatilization for several days, he said. Urea also increases soil acidity, requiring more frequent application of lime.
LSU AgCenter beef researcher Ryon Walker gave an overview of research projects at the Hill Farm and Red River research stations. Projects include a study of parasites that have become resistant to deworming treatments such as Ivomec.
Research is showing a treatment using different combinations of dewormers several times a year provides improved results.
Another study is looking at calf performance based on cow size. Walker said larger cows may not result in larger calves at weaning, and larger cows may require more feed than predicted.
Ryegrass can be substituted for alfalfa to make baleage, said Mike McCormick, director of the LSU AgCenter Southeast Research Station at Franklinton. Special wrapping equipment is used to sheath round bales in several layers of plastic sheeting, protecting the hay from the elements.
Ryegrass has the potential for 18 to 20 percent protein, which is comparable to alfalfa.
Ryegrass intended for baleage should be fertilized between Feb. 15 and March 15 and harvested at the boot stage with a drydown of 40 to 50 percent moisture.
Producers also heard details from Mike Barrington, of the Louisiana Department of Agriculture and Forestry about the new federal animal identification regulations that will allow traceability of livestock moved across state lines.