NONCHEMICAL APPROACH CAN REDUCE PRESENCE OF HERBICIDE-RESISTANT WEEDS

Arkansas research shows the heat of narrow-windrow burning destroys seeds.

- Laurie Bedord

Jason Norsworthy and researchers at the University of Arkansas System Division of Agriculture have found a potential nonchemical option for growers to diminish the distribution of weed seed to the soil using harvest weed seed control (HWSC) mainly from narrow-windrow burning.

Weed control programs need to shift toward strategies that use nonchemical approaches in conjunction with current herbicide programs if herbicides are to continue as a sustainable and effective option for growers.

Commonly used in Australia, narrow windrow burning poses a viable option to growers for commons weeds including barnyardgrass, hemp sesbania, Italian ryegrass, johnsongrass, Palmer amaranth, pitted morningglory, prickly sida, sicklepod, and velvetleaf.

An experiment was conducted at the Altheimer Laboratory in Fayetteville, Arkansas, to determine the temperature and duration needed to kill the weed seeds listed. Viability was initially determined for the seed of each weed species. Seed samples were then placed inside a high-fire kiln and subjected to 20 combinations of temperature and durations.