by R. L. Dalrymple
Perhaps, for those of you who are unfamiliar with the crabgrasses in general and the Red River crabgrass variety in particular, it might be helpful to jump ahead a bit.
Crabgrass is the name of a large group of warm-season Digitaria grasses. In some regions of the world, the grasses also are known by common names such as large crabgrass, hairy crabgrass, fingergrass, and sweetgrass. These grasses are, in general, characterized by being very successful natural reseeders, a bit "weedy," if you please. Just as annual ryegrass reseeds well for a cool-season plant, crabgrass can be managed easily for planned reseeding as a warm-season annual. The crabgrasses particularly are well known for their high palatability, quality, persistence, and ability to fit easily into winter forage–crabgrass forage double and single cropping situations. And the crabgrasses are basically nontoxic. That's sure nice!
So if the crabgrasses have all these nice qualifications, why haven't they been used more? By far the greatest reason is social stigma. My, how our minds get set in a rut.
You see, crabgrass became a serious weedy pest in the early days by invading tilled cotton, corn, gardens, and the like. And it definitely was a serious pest before the days of selective crop herbicides. It is not fun to hoe crabgrass out of a cotton row. I, too, have had that experience. So Dad, Grandpa, and his ancestors got eternally ticked off at crabgrass. They taught their progeny to hate it, too. Only a few brave souls allowed themselves to accept the good forage characteristics of the grass and use it. The situation is better today, but many folks still despise crabgrass because someone else told them to.
The second reason that crabgrasses haven't been used aggressively is because there was not any proven, known variety available, which is no longer true, and that is the real story herein.
Historical Perspective
 Figure 1. Research plots showing some difference in RR874 (now 'Red River' crabgrass) and a so–called good native type. | For fun, and a little academic knowledge, let's consider the history of crabgrass a bit.
The crabgrasses supposedly evolved on the African continent. Europeans collected seed and took it back to Europe. There is no doubt in my mind that crabgrass seeds came to America with our European forefathers simply as a contaminant in some feeds and seed stocks. But in 1849 the grasses also were imported by forerunners of the United States Department of Agriculture for draft animals and other livestock. Fulfilling that need apparently was a serious problem in those times. I doubt there was any plan to import only certain species and ecotypes.
From a personal perspective, I came to know crabgrass as a managed forage on my parents' farm in western Oklahoma. Dad had a planned crabgrass pasture – the first I ever knew of in my life. I don't know when he started his pasture, but I became conscious of it about 1948 when I was a youngster accompanying him to the fields.
So parents, be careful what you do around your youngsters. There is no way to know where your actions may lead!
Even as a boy I knew Dad's crabgrass pasture was different. Several of our neighbors grew common, Piper, and California sweet sudangrass. I asked Dad one day why he grew crabgrass and not sudangrass like the neighbors. He replied, "Well, son, I observed when I planted the sudangrass and redtop cane that the crabgrass always came. It made most of the yield. The milk cows love it. So I just decided to leave the sudangrass seed in McNeil's Seed Store and just grow crabgrass." All it took was a one-way plow running 3 inches deep in March. Lots of crabgrass pastures have started in similar ways.
That early learning stuck with me through school and college and into my professional life. During 1971–72, an opportunity to use the Noble Foundation Pasture Demonstration Farm to study a stand of "native" crabgrass came. The boss said, "Go to it," and I have been at it ever since. That same first pasture has just gone into its 24th consecutive year without a failure in either the crabgrass or winter pasture phase1.
During the early stages of our work with the crabgrass pastures, we observed a great variation in plant type, structure, size, height, and other characteristics. We collected specimens from our pastures, Dad's old pasture, other Oklahoma locations, New Mexico, and Missouri to study that difference, and, vive la difference, 'Red River' crabgrass was born.
Since the release of 'Red River' crabgrass, we have compared it to specimens from Delaware, Louisiana, New Zealand, Russia, other Oklahoma locations, and selections out of 'Red River' crabgrass. So far, the variety still stands at the top, but we continue to look for better ones.
1. This pasture went 25 years without failure through 1997. However, the summer of 1998 was one of the driest on record; There was no rain to produce a stand until too late in September. Crabgrass was grazed, but there was little of it.
Species and Ecotypes
'Red River' crabgrass came from one plant of hairy crabgrass: Digitaria ciliaris.
Dr. Ron Tyrl of Oklahoma State University advises me that there are 235 species of crabgrass (Digitaria) in the world. There are thirty-five species in the United States, with six species represented in Oklahoma, nine in Texas, and five in North Carolina. A naturalized crabgrass occurs in every state except, possibly, Alaska, and I think there is some there in a warm crack in the asphalt in downtown Fairbanks. So it is that there is incredible variation in species.
Equally important is that there is incredible variation of ecotypes within one species. During the first seasons of experiments, we had ecotypes that produced only about 6 inches of growth all summer, while 'Red River' crabgrass accumulated over 7 feet of growth only feet away (figure 1). What type is yours?
|