by R. L. Dalrymple
Figure 1. Rotational stocking on 'Red River' crabgrass and other forage crabgrasses. These replacement heifers have just entered the 18-inch-tall paddock on the right after grazing the left paddock to a good 3-to 6-inch residue.
The quality of many, if not most, summer grasses is inferior to that of the highest–quality grasses, such as the cool–season annuals like wheat, rye, and ryegrass, so upper–level stock performance is unlikely. There are few exceptions, but one is pasture–type crabgrass that, when well cultured, can rival the quality of spring–phase annual cool–season grasses, especially during the first half to two–thirds of the summer season. With irrigation or good rainfall and adequate soil nutrition, the same can be true to the last regrowth; therefore, good crabgrass can equal the top–quality cool–season grasses for forage or hay production. This characteristic makes crabgrass a wise choice to fill the quality gap in summer–integrated forage approaches.
Crabgrass can be a stand–alone forage in a special stock enterprise not dependent on anything else. However, its most common use is in various double cropping (double pasturing) or mixture situations. Very common among crabgrass graziers is the use of the grass as a planned volunteer summer forage following winter small grains pasture, hay, or grain production, including all the small grains: wheat, rye, barley, oats, and triticale. In the southeastern United States, from southern Oklahoma throughout the Southeast, this rotation also includes annual ryegrass and cool–season legume syndromes. It is a relatively easy approach to manage into perpetuity.
The livestock grazed on crabgrass run the gamut of beef stockers to cows, dairy cattle, sheep, horses, and a few others. The grass is excellent for any stock for upper–level performance, high average daily gain, good dairy cattle lactation, and the like. Of course, it also is good for other stock, but as a premium–quality forage, it is often most wisely used for production stock for direct income.
A species of crabgrass grows in every state except Alaska, but I suspect if someone looked closely, some could be found there around people, tucked away on the warm south side of a hill. But from a practical point of view, the grass as a forage is most successful from Maryland to central Missouri to southern Kansas to the Texas Panhandle and south and east to the respective coasts: in effect, the southeastern quarter of the United States. Crabgrass is a warm–/hot–season grass; therefore, it does best and has the longest season in the hotter regions within the above–mentioned geographic areas. We are aware, though, of successes into Colorado, the Dakotas, Illinois, and Ohio.
The growing season in southern Oklahoma is 120 to 180 days, depending on culturing. The actual grazing season runs from May or June to fall or winter, depending on the use imposed upon the pasture.
Crabgrass is best adapted to the various sandy loam soils. It does well on loams but only marginally well on clay loams, especially during wet years, or under irrigation. Silt and clay soils are unsuitable.
In Oklahoma, there are six different species, and in Texas, nine. In addition, within each species there is incredible ecotype variation of at least ten– to twelvefold in forage yield, which is why I mentioned pasture–type crabgrass. It isn't all good!
The grazier can erase some of the risk of using lower–yielding types by using a proven variety or native types. The relatively new Red River variety has been technically researched and developed and was released because of its record of high comparative yield potential and other good characteristics. So–called good native types usually yield 25 to 50 percent less than 'Red River.' Seed is available.
Long–term stocker steer and heifer performance on good crabgrass pastures has averaged over 1.8 pounds of average daily gain (ADG). Some herds on excellent pasture produced over 2.5 pounds of ADG. Such gains are indicative of forage quality.
Dairymen using good crabgrass pasture as a lactating cow forage repeatedly state that milk production increases 25 to 30 percent when the cows graze the pasture or are fed good crabgrass hay or silage, apparently because of higher palatability and digestibility and good protein content.
Of course, crude protein (CP) is critical. Well–cultured crabgrass can be 25 to 30 percent CP in the first growth cycle. Midsummer regrowth cycles have produced forage with 15 to 20 percent CP or more. Late summer regrowth on dry land, when fertilizer also is low, may have less than 10 percent CP. Remember, CP content is limited by available nitrogen; high nitrogen content equals high CP.
An even more important factor is digestibility. Tests have shown good crabgrass has 10 to 15 percentage points more digestibility than 'Midland' bermudagrass, a relative difference of up to 25 percent.
A major advantage to crabgrass pasture is that it can be managed for planned volunteer stands simply by letting some seed develop each year from June to fall. Of course, other cultural practices must be appropriate for total success. Still, some graziers prefer to ignore that approach and just overseed a little each spring.
The double–cropping approaches so popular with crabgrass are initiated several ways, sometimes simply by happenstance. The usual approach is to plant the winter crop and then overseed with crabgrass and let stock tread it, a low–input approach. The alternative method of crabgrass establishment is to prepare a good seedbed at the winter crop's end and plant the crabgrass seed. Conversely, some graziers prefer to plant the crabgrass during spring to early summer, use it, and follow it with the winter crop planted on a seedbed or untilled soil. All approaches work and depend on the needs and philosophy of the grazier.
These are the days of land resource conservation awareness that can be attributed to concerned land managers or law. Crabgrass forage fits into the conservation niche because it forms a moderate sod and is a good soil cover. It can be minimally tilled and no–till planted to cool–season crops to leave residue for conservation compliance. I have asked many Natural Resources Conservation Service personnel to judge my crabgrass production areas. Without fail, they have stated the areas easily fall within compliance guidelines.
Crabgrass is becoming accepted. Dad was the first crabgrass producer I have known. He farmed it when I was a kid in the 1940s and '50s. Crabgrass was introduced in the mid–1800s for stock feed but succeeded too well and encroached on crops. Folks got mad at it! We don't have to loathe crabgrass just because someone told us we should. It was a weed problem before cash crop herbicides, but today's herbicides and cultural techniques almost eliminate its threat.
Crabgrass is a top–quality forage, so to heck with peer pressure. Peers don't pay the bills. Think about using it because it just might work for you.