COLUMBUS, Ohio — A common weed in Ohio may be effective in forage production, especially if mixed with other pasture species.
Ohio State University research ("Species Interactions with Quackgrass and Their Effects on Forage Production"), recently published in the journal Crop Science, found that quackgrass, as a productive forage species, yielded best when grown with a complementary species, rather than one that competed with it for resources, or even grown alone. The results point to the possibility of taking something considered a nuisance and turning it into a useful component of forage biodiversity.
Quackgrass is a common weedy perennial in Ohio. When present in fields with rotating crops, it is difficult to control, can spread rapidly and can reduce crop yields. However, in pastures the grass can be a useful forage crop.
"Quackgrass exhibits various characteristics (erect stem growth habit, high feed quality, adaptation to a range of soil fertility and long periods of seasonal growth) that make it ideal for forage production. It certainly puts a whole new spin on what exactly is a weed," said David Barker, an Ohio State University research grassland ecologist with the Ohio Agricultural Research and Development Center. "Its role as a weed is well-known, but its potential in mixtures with other pasture species is not. And that's what this study is all about."
The greenhouse research, led by Ohio State graduate student Traci Bultemeier, analyzed the growth habits of quackgrass when incorporated with orchardgrass and white clover, two common Ohio pasture species. The results, based on replacement-series experiments with two-week and six-week cuttings, found that yield for the six-week cutting was 43 percent to 58 percent greater than yield for the two-week cutting. Additionally, quackgrass performed better with white clover than with orchardgrass, and yields were 23 percent higher under a quackgrass/white clover mixture than when either species was grown alone.
"We found that quackgrass was quite persistent under both cutting regimes, and appears to be a rather tolerant species adapted to co-habitation. The grass is pretty robust under most production conditions," said Barker, an assistant professor with the Department Horticulture and Crop Science. "There does not appear to be much potential to control this species with close defoliation or with competition from another species."
Barker speculated that the differences in quackgrass performance point to the type of grasses the plant was sharing resources with. White clover is a legume and exhibits growth characteristics that support co-habitation. For example, whereas quackgrass grows vertically, white clover grows horizontally, contributing to differences in the way the plants capture light. On the other hand, orchardgrass is a grass and shares similar morphology with quackgrass, which could explain the competitive nature of the species in the field.
"We are not recommending a grower plant quackgrass or propagate it, but in a pasture where quackgrass is widespread, there could be an opportunity to take advantage of the forage characteristics of the plant that make it compatible with other common pasture species," said Barker.