As of the last week of July, less than 1% of the rice crop in Texas was harvested. However, I suspect this percentage will dramatically increase during the first week of August. According to the Texas Rice Crop Survey, rice acreage in Texas is about 140,000 which is up about 10,000 acres from last year.
I have received few calls from farmers with production problems during July, so this is good news. But fall armyworms continue to plague our rice crop. I have received reports that fall armyworms are attacking the grains as well as the foliage—this is new to me. Stalk borers—sugarcane borer and Mexican rice borer—can directly feed on rice grains and grasshoppers can do the same. Also, as you know, blackbirds feed on rice grains. Another bird problem can be cattle egrets which do not feed on rice, but can break over rice panicles when they walk on a thick canopy. They feed on invertebrates, like fall armyworms and grasshoppers.
Speaking of armyworms, I recently observed fall armyworms feeding on soybean flowers/blooms. This is very unusual because normally fall armyworms do not attack soybeans—their main hosts are grasses, not broadleaves. The field in question had a pretty good infestation of crabgrass which the worms were feeding on—doing no damage to the soybeans. However, the farmer sprayed for the grass problem which forced the worms over to the soybeans. I contacted my LSU soybean colleague, Dr. Jeff Davis, who said he has observed the same problem in Louisiana soybean fields this year.
I don’t know why fall armyworms are so bad this year, but I do know the results of their feeding are causing problems in organic rice. Earlier in the year, fall armyworms ate vegetative organic rice down to the water line. This delayed canopy coverage of the rice releasing weeds to compete with the damaged rice. Specifically, legume weeds, like sesbania, have become a recent problem. I know of no effective control—other than mechanical—labeled for organic rice. Sodium chlorate is not labeled, but some organic rice farmers have asked me if salt water will desiccate the weeds. I do not know the answer to this question, but I plan to put out a non-replicated test next week. I don’t have a whole lot of faith in salt water, but we will give it a try.
Stalk borer damage is showing up in the form of whiteheads. If you did not apply Dermacor X-100 to your seed, you can still control stalk borers with pyrethroids applied at 1-2 inch panicle and late boot/early heading. For more details consult the 2014 Texas Rice Production Guidelines which you can access here on Pages 75-77.
