By Dr. Mario A. Villarino, County Extension Agent for Agriculture and Natural Resources, Hopkins County, Texas
From time to time, the Hopkins County Extension Office gets calls on sandbur control in pastures and hay fields In general, if you had sandbur in a field last year and were unable to control them, there is a good probability they will be back season.
According to the Noble Research Institute, there are four products recommend for sandbur control in pastures and hayfields.
For a product to be recommend, it has to meet a few basic qualifications. First, it must be labeled for the crop it is applied to. It is illegal to apply a pesticide to a crop that is not listed on the label. Second, it has to work. In this instance, it has to control a large percentage of the sandbur when correctly applied. Third, it cannot cause undue crop injury when used according to labeled directions.
There are two broad ways to control sandburs. One is with a preemergent herbicide. This type of herbicide must be applied before the sandbur seed germinate. The only labeled preemergent herbicide for sandbur control in pastures and hay fields is Prowl® H2O.
It is labeled for bermudagrass and other warm-season grasses when in winter dormancy. In southern Oklahoma and northern Texas, the most common application time is February or very early March before the grasses break dormancy. There is a 60-day haying restriction and a 45-day grazing restriction if Prowl® H2O is used. Good results can be obtained from Prowl® H2O if it is properly incorporated by rainfall or irrigation within 10 to14 days of application. It is a fairly expensive treatment.
The other three products for sand-bur control in pastures and hayfields are post-emergent treatments. This means the products must be sprayed onto an emerged sandbur plant.
Pastora® is only labeled for bermudagrass, so applying it on any other type pasture or hayfield is illegal. It must be applied to very small sandbur, and the spray must contact the sandbur plant. For that reason, the bermudagrass should be grazed or hayed very short.
Roundup PowerMax® must be applied immediately after the first hay cutting. It is labeled for use at a rate of 10 ounces per acre on bermudagrass hayfields immediately after the first hay cutting. It will also control many annual grasses other than sandbur. It is important to treat as soon as possible after the first hay cutting.
The fourth product is recommend with caution. It is imazapic, sold under the trade names Plateau® and Panoramic 2SL. The caution is this product will stunt bermudagrass growth for a period of at least 30 days. Some varieties, such as Jiggs and World Feeder, are more prone to crop injury than others. It is labeled for use in most perennial grass species, including native range.
Always follow herbicide label instructions: The label is the law.
For more information on this or any other agricultural topic please contact the Hopkins County Extension Office at 903-885-3443 or email me at [email protected]