Fall is the ideal time for livestock producers to walk their pastures and assess what may need to be improved before next year's grazing season, a Purdue Extension forage specialist says.
"They should be assessing what's out there - the amount of grass and type of grasses, the amount of legume and type of legumes, and what weeds are there," said Keith Johnson.
The time frame for pasture improvement begins with assessing the pasture in early November, testing the soil and checking fences. Fall is a good time for repairing fences when temperatures are milder than the heat of summer and the cold of winter.
Johnson said pastures should have excellent ground cover and be around 30 percent legumes or 50 percent for lactating animals - that is, roughly two legume plants per square foot. Ideally, the remaining cover should be adapted cool-season grasses.
It is important for producers to test the soil if they haven't done so in the past three years. Special attention should be paid to pH, phosphorus and potassium levels. If lime is needed, it should be applied in the fall so it can begin to increase soil pH over the winter months. Other nutrients may be applied at the same time, especially if nutrient levels are low, or deferred to a spring application. Lime and fertilizer should not be applied to frozen soil so nutrient movement offsite can be minimized.
A list of soil-testing labs can be found at here.
Pastures should be evaluated for the specific types of weeds present as some are more problematic to control and some might be poisonous concerns if eaten by livestock. A plan for reducing weed problems should be developed now so proper control methods can be implemented in the upcoming year.
Johnson said overseeding is most successful if pastures are grazed down to about 3 inches high in the fall, a condition that borders on overgrazing. This reduces the amount of broadcast seed that can get caught in very tall residual vegetation and, therefore, have no opportunity to become a soil-anchored seedling.
Very late February and the first three weeks of March, before grasses become green, is an excellent time to overseed pastures with legumes or grass seed. That is also an acceptable time if not done in the fall to apply soil test recommended nutrients such as potassium and phosphorus, and to apply nitrogen to grass dominant pastures that will not be overseeded with legumes.
"What happens when you let nutrient levels get low is that the cost to get them back up is extremely high," Johnson said. "So it's best to keep what's needed and follow through with the application of the nutrients and the occasional soil test every third year or so to see if you're on course."
"To get the seed closer to the soil surface some may let livestock out over the pasture immediately after seeding or use a harrow pulled by a tractor," he said. "They need to be cautious because typically Indiana pastures in late March and early April can be fairly wet, and if we're not careful the hoof action can do more damage than good."
Source: Purdue Extension