Native or Introduced Grass — Which Pasture Is Most Efficient for Stocker Operators?
By Lorie Woodward Cantu
Editor’s Note:This is the ninth installment in a 12-part series on stocker cattle management. This series has been created in partnership with Chris McClure, Gold Standard Labs (bvd-pi.com), a lab services company based in Hereford that specializes in BVD-PI testing and blood pregnancy tests; and Danna Schwenk and Karla Whitmore, CattleXpert Management Software (cattlexpert.com), a software company based in Elkhorn, Neb., that specializes in feedlot and stocker management applications.
The “sweet spot” for marketing cattle to feedlots changes depending on the price of corn.
“When corn goes up, the cost of gain in feedlots goes up,” says Dr. Jason P. Banta, Extension beef cattle specialist at the Texas A&M Agri-Life Extension Center in Overton. “To help control that cost, feedlots seek larger animals that require less time on feed to finish out.”
For instance, when corn was $2 per bushel, it was not uncommon for feedlots to buy freshly weaned calves weighing 350 to 450 pounds and feed them for 250 days or longer.
For much of the recent past, the optimum beginning weight was 700 to 750 pounds.
Today, with corn prices hovering in the $5 to $6 per bushel range, and spiking up to $8 per bushel, feedlots are buying cattle as heavy as 850 to 900 pounds.
“When corn is high, it is advantageous to get gains on grass,” Banta says.
In Texas and Oklahoma, grass programs for stocker cattle traditionally take 1 of 2 forms — grazing on winter annuals or grazing on native pasture in the summer. Although less common, some stockers are also grazed on warm-season annuals such as sudangrass, sorghum/sudangrass hybrids or introduced warm-season perennials like Tifton 85 bermudagrass.
Winter programs
Winter grazing on ryegrass or small grains such as oats, rye, triticale and wheat is the most common grass program. These forages are planted, depending on latitude, from late August to mid-October. To be economically feasible, average daily gain on these forages should generally range from 1.5 to 3 pounds per day.
Typically, these plants provide light grazing through the fall and winter and produce the bulk of their forage in the spring. When the weather cooperates, cattle can graze on these pastures through April and as late as mid-May.
Because the forage production increases exponentially in the spring, winter programs offer a grazing management challenge.
“To optimize income, both average daily gain and gain per acre must be optimized,” Banta says. “It’s important to understand the relationship between the 2 concepts. Average daily gain increases as the stocking rate or grazing pressure decreases; however, gain per acre increases as the stocking rate increases until the pastures become overgrazed, then gain per acre starts to decrease.”
To complicate this further, the amount of forage produced by winter annuals increases exponentially during the growing season.
“Appropriate stocking rates of cool-season annual grasses can increase 3-fold from fall-winter grazing to spring grazing,” Banta says. As a result, stocker operators must have a plan in place to deal with dramatic swings.
Options include using cows to graze excess forage; purchasing more stockers in the spring; purchasing additional stockers in the fall and maintaining them in a dry lot until spring; cutting hay or making silage.
Summer programs
In the summer, native pastures generally offer the best economic potential for stocker operators. Introduced warm-season perennial grasses such as bahiagrass and hybrid Bermudas generally require higher inputs and produce average daily gains ranging from .75 to 1.25 pounds, making them more suitable for cow-calf operations than stockers.
While native grasses produce the bulk of their forage over a 2-month period, they, unlike introduced perennials, tend to maintain their nutritional profile over time. Producers can more accurately assess the amount of forage available and stock accordingly.
“For a variety of reasons, it is feasible for managers to run stockers on native grass, even when average daily gains are less than 1.5 pounds per day,” Banta says.
Of course, the amount of forage available varies from year to year depending on weather conditions; therefore, managers generally decide each year whether or not this type of operation is feasible.
Nutritional considerations
Regardless of the forage type, managers must keep the basic nutritional requirements of the cattle in mind. The performance of stocker cattle is more sensitive to forage quality than any other class of livestock.
When establishing a goal for average daily gain, a manager must consider total digestible nutrients (TDN), crude protein and calcium. Nutrient requirements increase as average daily gain increases.
In the fall, wheat forage generally contains 25 to 30 percent crude protein and 65 to 75 percent TDN. These levels of protein and energy are adequate to meet the nutritional requirements of most stocker calves gaining more than 2.5 pounds per day.
In contrast, summer perennial grasses often lack the digestibility to provide adequate energy for high levels of gain. Table 1 illustrates the nutritional requirements of 600-pound Brangus-type steers at 3 levels of average daily gain.
Calcium comes into play because it is very often the first limiting nutrient of cattle grazing winter pastures, meaning that it is the nutrient that “puts the lid” on average daily gain. In other words, if the diet contains enough protein and energy to support an average daily gain of 3 pounds, but only enough calcium to support an average daily gain of 2.75 pounds, then the cattle will gain no more than what the level of calcium will support. This scenario is common when grazing cattle on small grains in the winter.
Mineral supplementation usually provides a good return on investment.
Other considerations
In early July, according to the U.S. Drought Monitor, more than 56 percent of the continental U.S. was suffering from moderate or more severe drought. This is the highest percentage recorded in the 12-year history of the service. Even large stocker operators, who as a matter of practice run cattle in several states to help mitigate the risk of drought, are affected by this weather event.
Obviously, a widespread lack of rain limits the amount of grazing available and increases the chance that small grains and other winter forages may not produce.
“The stocker business is a margin business, so when grazing is limited and concentrate feeds are expensive, it can be a very risky proposition even for experienced operators,” Banta says. “Now is probably not the best time for a novice to enter the stocker business.” The exception may be cow-calf operators who have stocked lightly and, as a result, have excess forage. It is likely that they could benefit from retaining ownership of their calf crop and using the excess forage to grow their own calves to a heavier weight, he says.
Producers who find themselves in this situation should spend some time considering their marketing plan if they want to benefit from heavier cattle, he says. For instance, if a cow-calf producer operates in a region that is known for producing 450- to 500-pound weaned calves, the buyers at the local auction are not necessarily going to be interested in a small group of 800-pound yearlings.
To make the most of the heavier cattle, the producers might need to haul the cattle to a market that routinely handles heavy weight cattle or they might need to work with other ranchers in the region to put together a load lot to be sold by video auction, he says.
“If producers invest their time, effort and forage in a set of calves, they need to take steps to capitalize on their investment,” Banta says.
If a cow-calf operator decides to retain ownership, it is important to understand that “bigger is not always better,” he says. Generally, feedlots keep cattle on feed for at least 100 days to achieve the finish and grain-fed taste that consumers expect. Smaller-framed cattle, those that will finish out at 1,100 pounds, need to go to the feedlot at a lighter weight than larger-framed cattle that will finish out at 1,350 pounds.
“Stocker operators have to be aware of a fine line when they’re putting weight on cattle,” Banta says. “While you want to maximize gain, you don’t want to get the cattle too fleshy or fat because that makes them less attractive and potentially less valuable to feedlot buyers. In a stocker operation, managers must always consider 2 questions. Is the weight gain cost effective? What does the weight gain do to the value of the cattle?”
“Native or Introduced Grass” is excerpted from the September 2012 issue of The Cattleman magazine.