Many of you know my friend and colleague Deidre Harmon. Deidre’s favorite question is “what is your favorite forage”? You might think that my favorite is tall fescue, but actually for many years my favorite forage has been Dallisgrass. Dallisgrass is a summer perennial grass that is native to Argentina. At one time it was commonly planted across the region in pure stands and especially in mixtures, but in recent years almost no one has intentionally planted it.
I began to notice a high level of Dallisgrass in some of our pastures about 25 years ago. If it was planted it was before we bought the farm in 1978. It is possible that the seed was brought in via purchased hay.
We experimented with fertilizing those pastures nitrogen during June and really could produce a lot of forage when summer rains came. When we were in drought times, and the drought did break in summer, dallisgrass was the first thing to come out and thrive. In many of our pastures there are now high levels of legumes (especially red clover) with tall fescue and orchardgrass in spring, and then Dallisgrass, crabgrass, purple top and other warm season grasses dominate during late summer.
When we first started managing for Dallisgrass we had occasional problems with Dallisgrass Staggers. The most memorable outbreak was following a summer drought. We fed the cows for about a month during August. One pasture being rested grew a lot of Dallisgrass seedheads which became infected. When it finally rained we turned the cows into that pasture and within two days we had 10 cows showing severe trembling or staggering. All these were young cows, with no old cows showing any symptoms. As I walked through the herd I saw other young cows going around selectively eating the infected seedheads. Several of these had muscle tremors in their necks. Most older cows were grazing more normally.
We immediately moved the cows to another pasture without much Dallisgrass. Most of the cases resolved in a few days, but one 3-yr old cow was severely affected. She struggled to stay on her feed, and we had to pull her out of a pond and a creek on separate days. She eventually recovered after a couple of weeks, and my parents named her Lazerina. She grew to be an old and productive cow.
The second time we experienced the problem was with one of our bulls. He was bad to fight, so he was in his own 1-acre pasture. There were some scattered seedheads which we didn’t pay much attention to as he had plenty of grass. I went into the pasture to look at him one day, and as I walked by him he startled and fell flat on his side before getting up and looking at me sideways. He had muscle tremors on his neck and on his side. I went straight for the bush hog and clipped the pasture. The next day the bull was fine and the problem did not reoccur.
Over the years I have learned to avoid this problem. Pastures with Dallisgrass are grazed aggressively during summer to prevent old seedhead development. This also provides high quality forage. I scout the pastures and if there is a lot of honeydew on my pants, or if there are over 10% of the seedheads showing visible infection we clip to about 12” before grazing. We clip the bull pasture several times throughout the summer.
I still worry when dealing with borderline situations. One of our finisher groups is grazing an area there a lot of Dallisgrass seedheads have developed. Even though these heads are getting old, only a few (1%) show the classical infected look. I am still worried, so I am giving the cattle daily sections so that they
will stomp down a lot of the seedheads rather than wandering around selectively grazing them. So far we have had no problems, but I still watch these cattle carefully daily for early signs of tremors.
Dallisgrass has been a critical part of our mixed pasture system at Triple Creek for many years. It helps us dilute the effects of toxic tall fescue while providing high quality summer forage. Dallisgrass staggers is something I don’t ever want to see again, so we put some special attention on preventing this malady.
~ Matt Poore, NC State and Chair of the Alliance for Grassland Renewal
The Alliance for Grassland Renewal is a national organization focused on enhancing the appropriate adoption of novel endophyte tall fescue technology through education, incentives, self-regulation and promotion. For more resources or to learn more about the Alliance for Grassland Renewal, go to www.grasslandrenewal.org
The Alliance for Grassland Renewal 