More on herbicide drift issues in Midsouth rice

In Tuesday’s RiceFax, one of our Extension contacts referred to the “irregular” nature of the suspected glyphosate drift damage he and others were seeing. We didn’t go into any explanation about what that meant. Space simply didn’t permit it.

A Mississippi farmer who called us this morning said that he also found that the damage in his own fields doesn’t look like previous episodes of herbicide drift damage.

“Before now, I might find that a corner or edge of one field had been really blasted by Roundup that blew over the property line,” said the grower. “This time, though, it’s kind of in streaks moving across the field. The rice looked okay up until we fertilized and flushed it, then it started turning brown.”

Extension workers have since looked at his rice and concluded that the damage was caused by glyphosate drift.

We’re hearing reports of the material moving quite a distance, upwards of four miles in at least one suspected case. As the farmer told us today, the damage was apparent as he drove down the road. “When I came to a tree line, it was still green, but on the other side of the tree line the vegetation turned brown again,” he said.

Nathan Buehring, Mississippi Extension Rice Specialist, has seen this same browning effect along roads in other affected areas.

Buehring and his colleagues have been trying to determine why drift damage is so much worse this year than in the past two seasons. One idea is that plants were already stressed due to cold temperatures and either too much moisture or too little, and that made them more susceptible.

Johnny Saichuk, Louisiana Extension Rice Specialist, also believes that atmospheric conditions may have promoted some of the long distance movement and streaking. In his Louisiana Rice Field Notes this week, Saichuk wrote: “When sprayed materials hang up in a layer of fog…it can be carried in unexpected patterns and destinations beyond normal considerations.” The result, he said, can be the irregular, streaked patterns being widely reported this year.

Growers in California’s Sacramento Valley probably see this kind of effect more than growers do in the Delta, which isn’t hemmed in by mountains. In 1998, one ag chemical company extensively tested a new rice herbicide in California rice and had no drift issues. The next year, though, conditions were different, and the compound moved a good deal, damaging fruit and causing a new set of problems for rice growers there.

In Mississippi, alone, 10,000 acres of rice will likely have to be replanted, and the number could go as high as 15,000, Buehring estimates. Another 20,000 acres has been affected to some extent by drift. The farmer who called us today said he was finding that at least some of the injured plants – initially assumed to be dead – are showing faint green growth, and their roots appear to be healthy. There’s every chance that at least some of those plants will rebound, he said. That further complicates the situation because the damaged plants will be starting over again almost as seedlings while rice that wasn’t hurt – or hurt as much – already is several inches tall. That will make for uneven stands and complicate management and harvest.

Drift issues have caught wide attention among both farmers and regulators in Mississippi. The state department of agriculture has been pulling staff out of other parts of the state to deal with complaints. Lester Spell, the state’s elected ag commissioner, was in the Delta, himself, last Saturday.

The long-term fear is that this year’s problems could lead to further regulation or limitations on how materials are applied.