As the year progress, our ranchers and farmers have initiated soil management and weed control programs into their ranch/farm. A common question I get later in the year is often related to weed control failure. As Ag producers start planning weed control programs, it is very important to identify weeds as they emerge in their fields. Sometimes weed identification can be challenging specially in early stages of the weed (many plants look alike when small) many times needing flowers or inflorescence for identification. A common basic herbicide strategy is to use a general herbicide to kill broad leaf- weeds. Many non-specific herbicides are based in 2-4D, a restricted use herbicide in the state of Texas. According to the National Pesticide Information Center (NPIC) 2,4-D is an herbicide that kills plants by changing the way certain cells grow. 2,4-D comes in several chemical forms, including salts, esters, and an acid form. The toxicity of 2,4-D depends on its form. The form also affects what will happen to 2,4-D in the environment and what impacts it may have, especially on fish. 2,4-D is used in many products to control weeds, and it is often mixed with other herbicides in these products. 2,4-D was first used in the United States in the 1940s. Products containing 2,4-D may be liquids, dusts, or granules. The liquid forms may be concentrated or ready-to-use. There are over a thousand products with 2,4-D in them that are sold in the United States. 2,4-D kills broadleaf weeds but not most grasses. 2,4-D kills plants by causing the cells in the tissues that carry water and nutrients to divide and grow without stopping. Herbicides that act this way are called auxin-type herbicides. It is often needed to do more than one application to obtain proper control, but since 2-4D is a growth hormone for plants it effect is not immediate. It is important that pesticide applicators allow several weeks after applying 2-4D based herbicides before deciding if a second application is needed. It is also important to remember to conduct weed control before temperatures get too high and weeds get into latent heat stress mode. 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].
Mario Villarino DVM, Ph.D.
Hopkins County Extension Agent for Ag and NR
1200B Houston Street
Sulphur Springs, Texas 75482
903-885-3443
