Common sense guides stockpiled forage management
Beef cattle can consume and obtain nutritional value from a variety of stockpiled forages to reduce the winter hay feeding period. Native grass, bermudagrass, tall fescue, crabgrass and bahiagrass are the five most common stockpiled forages in the Southern Great Plains. Four of these - native grass, bermudagrass, crabgrass and bahiagrass - are warm-season grasses that, when stockpiled, are usually grazed during winter dormancy following frost. The fifth grass, tall fescue, is a cool-season forage which, depending upon environmental conditions, can be actively growing during fall and winter. Each of these grasses can be useful as a stockpiled forage, but each comes with its own management considerations.
Greater stockpiled forage utilization (the allowable use of forage) is achieved for all grass types by restricting grazing access (strip, time grazing, etc.) instead of continuous grazing. Different forages, however, should be grazed to different heights. It is recommended that native grass never be grazed below 6 inches. Bermudagrass, bahiagrass and tall fescue should never be grazed below 3 to 4 inches. But management of stockpiled forages involves more than restricting grazing and maintaining grazing heights. It has been said that grazing management is an art based on science. Perhaps a better descriptor for "art" is "common sense," and the saying might read better as "grazing management is common sense based on science."
Cattle grazing stockpiled forages will graze the leaves first, leaving the seed heads and stems lightly grazed or trampled, depending on how restrictive the grazing. Picture a native grass range composed primarily of big bluestem, indiangrass and switchgrass, and deferred from July to frost as a stockpiled standing hay crop - it would be tall, fully headed and have a lot of mass. These grasses are bunch or semi-bunch types with crowns that we want to avoid damaging with grazing. If grazed to a 6-inch height, is this good for the plants? Is this good for the animal to consume the grass to a 6-inch height? Common sense says no, and that is correct. By the time the forage reaches a 6-inch height, cattle would have lost condition and plant crowns would be grazed too closely. In this case, attention should have been paid to the plant's leaf canopy area. Cattle should have been moved to a new area when the leaf canopy approached 6 inches, not the entire plant.
What if the range is primarily little bluestem, a grass that does not reach the height of the high seral grasses? Again, you do not want to graze down into the plant crown, and, by comparison, little bluestem would be grazed closer than the high seral grasses.
For bermudagrass and bahiagrass, which form more of a sod, common sense tells you to pay attention to how cattle are consuming canopy leaves. A bermudagrass or bahiagrass canopy with good canopy height (12 inches) at the start of grazing can deceivingly appear to have good height for a period of time after grazing. Walking the paddock, you may find leaves removed by grazing or shattering, leaving stems and little quality. The cattle should have already been moved.
Tall fescue is different. Fall stockpiled tall fescue is 100 percent leaf, and plants can actively grow through most of the cool season. Canopy leaves can be consumed to a 3- to 4-inch residual height. What we must be careful of is to make sure that we leave tall fescue with 4 to 6 inches of canopy height going into summer to aid persistence.
Are all these forage types able to withstand weathering and maintain their quality through fall and winter equally? Common sense says no, and that is correct. Crabgrass deteriorates rapidly following frost and should be grazed first, followed by native grass or bermudagrass, and then tall fescue.
Grazing management may be an art based on science, but that "art" is founded on a whole lot of common sense.