Controlling the Weed, Buckhorn Plantain, in Hay Fields and Pastures

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Have you ever bought or made hay and the pretty green bales have had long black broad leaves mixed into them? If so, it is most likely that those black leaves are from the Buckhorn Plantain. This is one of many plants, or weeds, that cattlemen and farmers struggle to keep out of their pastures and hay fields. Some fields end up with a lot more weeds than the intended grass that was originally planted. What causes this? Why do livestock owners care? How can a person keep Buckhorn Plantain from growing where it causes problems?

The truth is, it is impossible to grow a “pure” stand of grass. There will always be plants that volunteer from the “seed bank”, or from neighboring fields. We call these volunteers… weeds!

So why do we bother to control weeds?
1) Weeds have the potential to cause injury or death to livestock if the weed plants are toxic.
2) Weeds can reduce growth of good grass & hay production causing animals to eat less.
3) Weeds can interfere with hay drying.
For these reasons, weed control is very important.

Weeds can be controlled by taking the following steps. First, identify the weed or weeds. This allows you to determine if you even need to control the weed at all. Next, strengthen the desired grasses’ ability to compete against weeds by using lime and fertilizers. The amounts of these materials should be determined by soil testing, using the soil test boxes, forms, and instructions from your Cooperative Extension office. Once your soil pH and nutrient levels have been optimized, you can move on to other available methods, if needed. These methods include grazing management, mechanical (mowing and burning), biological, and chemical controls. The effectiveness of these control methods depends on timing and using these control methods in combination when necessary.

In this example we have identified our pesky weed. It is the Buckhorn Plantain, and it is one that needs to be kept out of our pastures. It has a large root, and is hard to destroy. This is a weed that cattle tend to not eat. It grows at the exact same time as fescue; so it ends up mixed in with harvested hay every year. Because there is no effective biological control for Buckhorn Plantain that we are aware of, the only real control tool we have beyond a good strong stand of pasture grass, is chemical control.

By definition, chemical control is the use of herbicides that kill weeds by inhibiting the plant growth process. Select an herbicide based on desired forage species, weed species present, cost, and ease of application. It is very important to apply herbicides at the correct time and rate. Consider spot spraying weeds if that is practical.

The best time to control weeds with herbicides in general, once they have already emerged from the soil, is when they are young and are actively growing. That time varies according to whether the weeds in question are cool-season weeds or warm-season weeds. The best cool-season weed control window is from October through December and if needed, it can be repeated from February through April. Warm-season weeds are best controlled from April to mid-July for most species. Buckhorn Plantain is a cool-season plant. The best time to spray it is in November. The 2020 NC Agriculture Chemical Manual (NC State University) recommends many sprays, but a cheap and effective one is 2,4-D ester. If the spray does not kill the weed, spray again in March. The 2,4-D ester product evaporates at 70˚F; therefore, spray when predicted temperatures are between 45˚F and 70 ˚F for 3 consecutive days. You will want temperatures as high as possible within that range, so the plant will draw in the herbicide. If the weatherman gets it wrong and temperatures go above 70˚F, the spray can evaporate and be carried by the wind to your wife’s flower beds, trees, or any broad leaf plant and destroy it. So check the wind direction for those 3 days and make sure they are blowing in a predicted direction that will not hurt plants. I use the Air Sports Net website. Click on weather and use the forecast box with your zip code. Look at wind predictions for 3 days since 2,4-D will evaporate for 3 days after spraying. Also, you will need a period without rain for at least 6 hours after spraying. I prefer to not have any rain for 24 hours after applying. Text me or call at 405.219.1902 if you have questions. Remember, always read and follow herbicide label directions, and pay attention to any grazing and haying restrictions. The label is the law!

Check out the N.C. Cooperative Extension of Lincoln County webpage for any food or agriculture questions, or call 704.736.8461.

Glenn Detweiler, Area Livestock Agent