Safe Herbicide Practices to Reduce Crop Damage Risk

By Blake Jackson

Herbicide drift remains one of the most common and preventable causes of crop injury. In many cases, the grower whose crops were damaged wasn’t the one who applied the herbicide often, a neighboring farm was responsible.

It’s crucial to understand that applicators are legally accountable for herbicide drift, making careful application and attention to weather conditions essential.

Spraying should be avoided when temperatures are high, winds are strong, or temperature inversions exist. Choosing the correct herbicide formulation can also significantly reduce drift risk.

Many herbicides, including 2,4-D, dicamba, triclopyr, and MCPA, are formulated as either amines or esters. While not all of these are used in vegetable production, they’re often applied to field crops, turf, and other non-vegetable areas near vegetable farms.

Understanding these formulations and selecting the right one can improve weed control while minimizing damage to non-target plants.

For example, 2,4-D-a widely used herbicide since the 1940s effectively controls broadleaf weeds but can harm sensitive plants like tomatoes, grapes, and ornamental flowers if it drifts. This drift often occurs due to volatilization, where the herbicide vaporizes and moves to nearby fields.

Ester formulations of 2,4-D tend to have higher vapor pressures, making them more volatile than amine salts. Amine formulations, though slightly less potent, are generally safer to use when drift is a concern.

Esters penetrate the plant’s waxy surface more effectively, which can enhance weed control, particularly in cool weather. However, as temperatures rise, esters become more prone to vapor drift and may even damage grasses, making amine formulations a safer summer option.

Ultimately, both amine and ester herbicides have valuable roles in weed management. Esters work best in cooler months and for hard-to-control weeds, while amines are preferable in warm conditions or when sensitive crops are nearby.

Regardless of formulation, applicators should always monitor wind speed and direction, adhere to product labels, and follow all safety recommendations to ensure effective and responsible herbicide use.

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