Pasture improvement is part art as well as science since there are a number of factors that seem to converge to make an optimal forage environment for your cattle. But sometimes you can have too much of a good thing, such as when your input costs to improve forages outweigh the benefits from additional gains on the animal. 

That creates a fine line given the variability in soil and plant types across the country, within states and even among different pastures; there’s no one right way to manage it. Granted you can observe a pasture and make a determination whether to pull cattle off, but in terms of making improvements to that land, you need to analyze the cost of the inputs and compare that to potential returns.

“It’s one of those things that is hard to say with real definition that you have to do this or it always pays to do that,” explains Larry Redmon, extension forage specialist at Texas A&M University.

As an example, he knows producers who run cattle on a warm-season, drought-tolerant, low-input grass who never soil sample and rarely add fertilizer. “From a bottom-line standpoint, some of those can be very productive because they have a low-input kind of grass and they’re not having to spend a lot of money on it. Their cattle, though, may not perform as well as similar cattle on a more productive grass like Bermuda. But to realize additional performance on that Bermuda, you have to spend money on fertilizer inputs to reach that. With the cost of nitrogen, phosphorus and limestone these days, any gains may be eaten up in input costs.”

The goal of any program is to improve forage production in a pasture at the least cost, but not such a low cost that the forage begins to decline or the cattle begin to suffer and are not able to realize their genetic potential. There are a number of strategies and inputs that you can utilize to improve pastures while keeping cost limited.

Stocking rates
Stocking-rate adjustments make the biggest impact on pasture improvement. Stocking rate is defined as the land area allocated to each grazing animal for a specific length of time. Typically, you can observe a pasture to determine if there are too many animals grazing since forage will be scarce.

“Producers need to have a good understanding of stocking rate since this is the one thing that can make or break a cow-calf producer quicker than anything, says Dr. Redmon. That stocking rate depends on where you’re at, the type of cattle you have and the types of plant community you have. But never base that rate solely on tradition.”

He points out that for some operations, stocking rates are determined by what has always been done. However, the number of animals that the land could handle 10, 20 or 30 years ago evolves. Your granddad’s average cow might have weighed 800 pounds, while your dad’s average cow might have weighed 1,000 pounds. But today your cows may weigh 1,200 pounds and unless you’ve purchased or leased more ground, then your stocking rates should have declined.

“We’ve almost doubled the stocking rate just due to the increased size of the animal,” he says, adding that producers are not always aware that dry-matter intake is linked to body size. Besides increased cow size, stocking rates need to be adjusted based on grazable acreage. You can find average-stocking-rate tables from your local extension service, but you still need to make adjustments based on your pasture quality and cattle type.

Forage needs nutrients —  nitrogen, phosphorus and potassium — from the soil. As you graze hay pastures over time, those nutrients decline. There are a number of ways to add these nutrients to the soil, but first start with a soil test to determine what nutrients are needed. In addition, a soil test will determine soil pH, which is important for certain grasses to reach optimal production.

“With introduced forages, you need to know the fertilizer requirement for those forages,” Dr. Redmon says. “Then look at how best to meet that soil-fertility requirement at the least cost.”

Nitrogen can be added to the soil using purchased fertilizer. Right now, nitrogen fertilizer costs are running high. To get the most for your dollar, follow application-timing guidelines for the type of grass and your region of the country. These guidelines vary, so check with your local extension service for the latest recommendations.

In addition, you may want to evaluate other opportunities to get those nutrients into the soil, such as applying animal manure. You might even consider changing a pasture-management scheme so that the cattle in the pasture move around more, helping move the manure.

Another low-cost method of adding nitrogen to the soil is interseeding with legumes. “If you’re looking for a way to cheapen the fertilizer bill each year, consider introducing legumes, like clover, into the pasture,” Dr. Redmon says.

A study at the University of Missouri Forage Systems Research Center near Linneus, Mo., compared the economics of applied fertilizer to adding legumes to grass pastures. That comparison found that the cost per grazing day was typically lower for grass-legume pastures than for N-fertilized pastures. In addition, animal performance was generally 5 to 20 percent higher on grass-legume pastures compared to N-fertilized grass, which lowered the cost per pound of gain even more.

Bruce Anderson, University of Nebraska agronomist, points out that to get the most for your dollar, you need to manage grazing on fertilized pastures so more of what you grow actually gets eaten. “This will happen if you subdivide pastures with some cross-fences and control when and where your animals graze. Give animals access to no more than one-fourth of your pasture at a time, or even less, and then graze off about one-half of the growth before moving to another subdivision.”

Weed control
Herbicides exist to help control weeds. Before you start spraying, however, look at the big picture. If your pastures are overgrazed, then you may need to make a large-scale change to your pasture management. “If there’s something broken with your stocking rates and fertility management, then you’re going to see more weeds and need more herbicide. Competition and prevention are the best thing to stay ahead of it,” Dr. Redmon says. “Prescribed burning is another option to reduce weeds and other undesirable species.”