Scattered showers are helping some farmers in the Texas Southern and High Plains, but large areas of drought still exist and water resources are being stressed to meet weekly crop needs. Recent rainfall in some South Texas areas has broken a drought cycle but could set up some pre-harvest problems for cotton and grain farmers.
Monti Vandiver Texas AgriLife Extension Integrated Pest Management agent serving Bailey and Parmer Counties, says recent crop progress has been good.
“Based on area average long term weather data from 1981-2010, crops have progressed very well over the last 10 days or so,” Vandiver says. “Slightly lower temperatures have helped moderate moisture demands a bit. A few scattered and very isolated rains certainly helped those fortunate enough to be in their paths. We are still in need of a good area wide rain as crops are demanding more moisture than most irrigation systems can supply.”
He says area weather stations have recorded 4.19, 5.46, 4.29 and 7.3 inches of rainfall year-to- date versus the 30-year area average of 10.10 inches. “This shortfall continues to tax irrigation systems at an elevated rate,” he says. “Some crops will stress more than others without timely rainfall soon.”
Potential weekly water use—crop Inches per week—show that corn needs 1.98 inches; cotton 1.95 inches; and sorghum 1.5 inches per week.
Haves and have nots
Kerry Siders, IPM Hockley and Cochran Counties, says the area has been “in pretty good shape up to this point. However, I am concerned that we are again seeing, as last year, ‘the haves and the have nots’ of irrigation water.
“Decisions about prioritizing fields that share water, or portions of fields with limited irrigation capacity and lack of rainfall must be made now to limit crop/yield losses. When I compare our cotton crop to the same time the last couple of years, we still are in a good situation if the weather would just cooperate. So I do hold out some optimism about our yield potential.”
He says cotton conditions for the average field in Hockley and Cochran Counties would be:
- Average number of total nodes is 16 (range 10 to 18);
- Fruiting branch at node 7.3 (range 5 to 9;)
- Square retention of first positions is 88 percent (range 72 to 99 percent);
- Node length is 1.1 inch (range of 0.6 inch to 2.6 inch);
- Plant populations average 39,780 per acre (range 23,500 to 59,500;
- Average blooming plant has 8.7 nodes above white flower (NAWF).
“I am seeing a few more blooms and small bolls daily. The milder weather over the past couple of weeks has allowed the plant to make very good progress in terms of both vegetative and reproductive growth. We are going into bloom with close to 9 nodes above white bloom. This places first bloom (50 percent of all plants in field with bloom) on most early fields at July 14, with most fields hitting first bloom at around July 23. This is a full week earlier than last year.”
Siders says local grain sorghumfields should be monitored for aphids, mites, head worms and midge. “No major problems have been detected or reported. Stay on top of weeds.”
He says peanut farmers should monitor fields closely for foliar diseases and pod rots. “Wrap up any fertilizing and stay on top of weeds. No major issues were reported or found this last week.”
Clyde Crumley, IPM agent for the Upper Gulf Coast, says the dry weather pattern that has persisted for several weeks has been “broken up by a series of gulf disturbances, with rainfall this past week varying from 2 inches to more than 4 inches.
“Grain sorghum and corn harvest should be occurring now, so some rain would not have hurt us too much. Unfortunately that is not always the case and we are seeing seed sprouting in the sorghum heads and some minor lodging in corn.”
Crumley says most of the area’s cotton is at physiological cutout. “The next hurdle for cotton will be protecting the bolls from insect damage. Research has shown that small bollworms will not feed on bolls that are more than 350 heat units past bloom; stink bugs will not feed on bolls past 450 heat units; lygus 350 heat units. For verde plant bugs, we are not 100 percent sure, but our best guess would be it is similar to lygus.”
Crumley sees a distinct possibility that some fields will experience re-growth. “With this restarting of the crop all of the issues that go with that are possible. In the case of cotton—where a lesser amount of rain was received and fields are well drained, where multiple treatments were applied for various insects and where a plant growth regulator was used at sufficient rates—the crop still looks good. With continued rain, boll rot is not only a concern but a real possibility.”
He says most of the crop has been made and bolls are present to the upper tier of the plant. “With all that said, we are continuing to monitor for bollworms, fall armyworms, stink bugs, spider mites, aphids, Lygus and verde plant bugs. Beneficial insect numbers in cotton are moderate to high, with lady beetle adults, larvae, big eyed bugs, and tremendous numbers of minute pirate bugs observed.”
John Norman, editor of Pest Cast Newsletter and retired Texas Extension entomologist saysmost of the week in the Lower Rio Grande Valley “was hot and dry with occasional sea-breeze-driven scattered showers thrown in for good measure. Most fields around the Valley received little or no rain, but a few isolated fields, particularly in southeastern Cameron County, received in excess of 4.5 inches.”
Norman says other spots in western Willacy County received more than 1.5 inches.
“Grain sorghum and corn harvests were continuing with most of the grain harvest finished,” he said. “Corn still has a little ways to go and cotton harvest will probably go to near the end of August.
He says many cotton fields were scheduled for defoliation this week and even more will be next week. “Harvest was increasing, but most of the area fields will not be harvested for at least another two weeks. A few fields were being irrigated for the final time this week.
He says Whiteflieswere about the only pest of concern in less-than-mature cotton.