Wet year prompts weed challenges in crops

Uncharacteristically wet weather this year has left many producers across the state with a growing weed problem, according to a Texas A&M AgriLife Extension Service expert.

Scott Nolte, Ph.D., AgriLife Extension state weed specialist and associate professor in the Texas A&M Department of Soil and Crop Sciences, Bryan-College Station, said widespread drought during previous seasons allowed producers to keep weed growth in check. However, moisture is becoming a challenge this year due to weed growth and producers’ inability to control it.

“Some areas, like the South Plains, have had good moisture, but it has kept them out of their fields,” Nolte said. “They don’t typically have that this time of year, so they have been delayed probably a month getting cotton planted.”

Another problem, he said, is some production areas were dry early, and preemergence herbicide applications did not get good activation. Now, producers are relying on postemergence treatment, but it has been difficult to access fields between rains to spray or cultivate.

Delayed canopy production allows weed growth

Good growing conditions in the Coastal Bend helped crops to reach canopy faster than usual, which prevented many weeds from establishing themselves. But not all areas were able to plant the crops on schedule.

Canopy development typically reduces the amount of sunlight available for weeds to germinate and grow, Nolte said. But repeated rainfall and delays in planting put canopy development behind the rapid growth of weeds in some regions.

Now, producers need to make postemergence herbicide applications to clean up weeds after preemergence herbicide applications were no longer effective and plantings were delayed. 

“Typically, we have drier conditions going into July, and it slows weed growth down, giving the canopy time to close up, which takes care of this problem,” he said. “In areas with more rainfall than normal, we’re getting a lot more germination of weeds later in the middle of July.”

If weeds get above the crop canopy in cotton and sorghum, Nolte said producers will face issues during harvest. Producers also need to control those weeds before they produce seeds that could germinate next season.

Weeds to watch for

Producers in the Coastal Bend and areas around College Station are seeing more sedges this year because the rainfall has been steady and above normal, Nolte said. Sedges thrive in high humidity and moist conditions.

Other weed problems reported are Palmer amaranth, some jungle rice and glyphosate-resistant johnsongrass, he said. Johnsongrass causes more issues in years with abundant moisture.

“Roundup is not going to work if they have the resistant johnsongrass, so they just need to know if that is the problem going into the next season,” Nolte said. “Because if they try and spray glyphosate to control it next year, and it doesn’t work, they’re going to be a couple of weeks behind in control. The weeds will get established and be more difficult to control when they are bigger.”

Also, dicamba is not an option this year, he said. Depending on the crop they planted and what they are allowed, 2,4-D, glyphosate or glufosinate will be the treatment choices. Glufosinate is working better in high humidity and good soil moisture this year, Nolte said, although the weeds need to be smaller for it to be effective.

Pay now or pay later

In cotton, the most critical time to control weeds is in the first three to four weeks, when weed competition will reduce the yield the most, Nolte said. But keeping the crop clean before full canopy is also important.

With lower crop prices and higher costs, budgets are tight, and many producers are trying to control their inputs, he said. They may be tempted to leave late-season weeds because they don’t impact yields that much.

But weeds left unmanaged this year will continue to be a problem next year.

“Any weed left will have the potential to produce seed, and that problem is going to be there next year,” Nolte said. “Then you’re going to have higher weed pressure and have to spend potentially more on weed control.”

AgriLife Extension district reporters compiled the following summaries:

Panhandle

Scattered showers fell across the district. Overall soil moisture levels were reported as short to adequate, and overall crop conditions were fair to good. The delayed wheat harvest was wrapping up. Some corn had begun to tassel, and humid, mild conditions were excellent for pollination. Producers were cultivating and spraying fallow fields behind harvested wheat. Most grain sorghum fields had excellent stands and adequate subsoil moisture to support growth and development until heading. Rangelands were green, and most pasture grasses were in the seed development stage and maturing. Cattle gains on grass were excellent. Pasture and range conditions were fair to good.

South Plains

Spotty showers fell throughout the week and subsoil moisture was good. Cotton was squaring, and sorghum was starting to head out in the earlier-planted fields. Hay grazer and other crops looked good. Pastureland and livestock were in good condition across most areas.

Rolling Plains

Late spring and early summer rains continued to benefit the district; however, topsoil moisture was quickly drying up. Cotton crops, Sudan grass and hay were looking good in most counties. However, with all the previous rains, weed control was a challenge. In addition, multiple counties were reporting a rapid increase in the grasshopper population. Livestock were still in a great grazing position heading into the hottest months of the year.

North

Flooding occurred in some areas, and temperatures were warm with high humidity levels. Cotton looked good, although some fields were slightly behind in development, and some plants were lost to flooding. Hay conditions remained good. Rice conditions were fair to good. Corn matured through the dough stages in most fields and some varieties were drying down rapidly. Sorghum was heading, maturing and turning color. Soybeans were maturing through bloom/flower stages, and some had completed pod set. Insect populations were present but not dramatically high for any crops, except for grasshoppers in pastures, which were increasing to treatable levels. Forage and hay crops were in excellent condition due to additional rainfall. Some producers were working on their second cutting of hay. Range and pasture conditions were mostly good to excellent and continued to improve due to rain. Livestock conditions were excellent. Summer annual weeds were maturing rapidly and exhibiting rapid growth rates with the heat and rainfall. Cattle looked good with more grass than they can eat this time of the year.

East

Most of the district continued to have sporadic rain showers. Subsoil and topsoil conditions were adequate. Hay production slowed due to the constant moisture. Pasture and rangeland conditions were good. Cattle market prices remained strong but with decreasing head counts. Livestock were in fair to good condition.

Far West

Another 1-3 inches of rain fell across the area, accompanied by cooler-than-normal temperatures. Several fields were excessively wet, whereas others were now dry enough to resume fieldwork. Weed control was the primary issue as growers needed to spray and cultivate. Cotton fields needed warmer temperatures and heat units. Most corn was in the dent stage, with dry-down expected soon. Sorghum was either blooming or in the soft dough stage. The melon harvest was in full swing; however, rains continued to keep harvest crews out of the fields. Pecans looked great, with heavy loads and large nuts. Pastures were greening up from the rains, and the grass was recovering better than expected from the prolonged drought.

West Central

Record-breaking rainfall continued to fall, with totals ranging from 5-15 inches over 10 days. The torrential rains left many fields underwater or too muddy to access. Cotton conditions varied, with some fields thriving and others suffering from flooding, particularly in low-lying areas, where up to 60% of the crop was lost in some places. Late planting left some cotton slightly behind schedule. Farmers began chiseling fields in preparation for wheat planting, and overall hay production slowed due to persistent wet conditions. Hay and forage crops benefited greatly from the moisture, with some producers already cutting a second round of coastal hay and preparing to harvest Sudan grass. Pecan trees showed noticeable improvement. Tanks were full or overflowing, and cattle remained in excellent condition with more grass than they could consume.

Central

Counties across the district experienced record rainfall and extremely wet conditions. The abundant rainfall filled stock tanks though flooding occurred in some areas. Corn progressed well toward maturity. Cotton was blooming and maturing bolls, with recent rains helping to maintain a fruit load despite increased pest pressure from bollworms and stinkbugs. The wet weather limited field activities, while corn and cotton needed more sunshine for optimal development. Pasture conditions improved. Hay producers resumed cutting and baling when fields dried sufficiently. Fall armyworms were reported in multiple counties. Livestock remained in good condition.

Southeast

Recent weather across the district brought persistent rainfall and high moisture levels that delayed fieldwork. Soil moisture conditions ranged from adequate to surplus across the district with many areas reporting saturated soil. Crop progress was generally positive despite weather challenges. Corn was silking in many areas, with some counties showing progress toward maturity and harvest. Rice was fully planted and emerged in some locations, with heading in progress across others, though untimely rains raised concerns about interference with flowering and an uptick in weedy rice. Sorghum was nearly fully headed and coloring, showing strong development. Cotton was fully planted and in good condition. Winter wheat and oats were completely harvested. Wet conditions and limited dry intervals slowed hay harvest operations and reduced quality, especially where previously cut hay was exposed to rain. Daily showers and thunderstorms further complicated second cuttings. Standing water in low-lying areas began to recede amid lighter rains. Pasture and rangeland conditions were mixed. Livestock conditions reflected this variation, with reports that ranged from 5% poor to 30% excellent. Overall, the rainfall supported good forage growth, and ponds held adequate water. Cattle and other livestock generally remained in stable condition despite weather-related delays in forage harvesting.

Southwest

Intense storms delivered 3.5-6.5 inches of rain and cooler temperatures. Soil moisture conditions improved with the heavy rain; however, wet conditions delayed fieldwork and harvest. Row crops looked good to excellent. Corn and sorghum harvests were both starting. Some producers expected to lose their grain sorghum due to the excessive rainfall received. Some cut hay will be lost to rotting due to a lack of drying time. Other hay fields and pastures looked good and should produce good hay yields for the upcoming winter. Pasture and range conditions continued to improve. There were some reports of armyworms in improved pastures. Livestock markets were strong to steady. There was a report of stomach worms affecting livestock and whitetail deer. Overall, livestock and wildlife conditions were steadily improving due to better pasture and browse conditions.

Coastal Bend

Rainfall kept farmers out of the fields in some areas and delayed harvest. Combines were steadily harvesting early grain sorghum and a little corn when they could get into fields; producers moved to drier fields as needed. Yields on early planted grain sorghum were decent. Rice was almost all headed. The cotton crop continued to look promising and responded well to recent rains. Haymaking was a challenge, with harvesting as weather allowed, but supplies looked good. Range and pasture conditions remained mostly fair to good with adequate rainfall, though some areas without recent rain were starting to burn up. Pastures were producing forage. Livestock were in good condition for the most part, and calves were gaining weight.

South

The area experienced triple-digit temperatures and high winds, accompanied by above-normal rainfall. Topsoil and subsoil conditions were adequate. Crops looked good with promising yields. Hay producers were cutting and baling. Peanut planting wrapped up. Producers resumed harvesting grain sorghum, sunflowers and corn. Some damage was reported to grain sorghum due to excess moisture. Cotton continued to progress and set bolls. Citrus trees were also doing well as fruit continued to mature. The cantaloupe harvest was wrapping up. Peas were being harvested. Range and pasture conditions continued to improve. The grass was green and growing. Beef cattle, livestock and wildlife were benefiting greatly and were in good condition. Beef cattle producers were scaling back on supplementation, and feed prices were still high. Beef market prices remained high as cattle supplies continued to be low. Wildlife continued to thrive. Whitetail does were fawning, and turkey and quail were beginning to hatch out.