- Flowering winter wheat very sensitive to freeze damage.
- Cold, wet slowing crop emergence, development.
- Wet soil leaves plants vulnerable to seedling disease, seed rot.
Arkansas’ row crop farmers will be keeping a wary eye on the thermometer Friday and Saturday (May 3 and 4) as a front that has already brought record lows and snow to the state, fills the air with its coldest punch yet for the young month of May.
Jason Kelley, Extension wheat and feed grains agronomist for the University of Arkansas, said there are worries among winter wheat growers because the crop is flowering, the crop’s most sensitive stage for freeze damage. “Temperatures down to 30 degrees just for a little while could cause significant damage. Fortunately most forecasts are calling for lows that will be above freezing; hopefully we can dodge another bullet.”
The National Weather Service at Little Rock was forecasting Friday night’s low at 36 degrees. In northwest Arkansas, a freeze watch was issued through Saturday morning.
Kelley, and Jarrod Hardke, Extension rice agronomist, noted how different spring 2013 was from spring 2012.
“Last year we were starting to irrigate corn by now,” Kelley said.
For rice growers, “we’re talking about a two-month shift from one year to the next,” Hardke said. “I’ve never seen such a difference in back-to-back years. Last year it was a desert, and this year, you need a boat.”
Even without a freeze, the cold and wet is still causing headaches for row crop growers. The wet conditions have slowed planting for farmers and the cold has slowed plant development for nearly all crops.
Blake McClelland, Extension cotton verification coordinator, said that very little of the state’s cotton has been planted, but “any that has been planted will be in danger of root tip damage and seedling disease from the combination of cool wet soil. As of right now, the forecast for next week looks much more favorable for cotton planting.”
Hardke said rice planting has been uneven around the state, so weather effects would be highly variable. “Soil temperature is a problem with rice,” he said Friday morning. “Rice is planted more shallow than other crops; typically an inch deep or less. Other crops are more buffered from changes in air temperature.” Hardke hopes the last few weeks of warmth would mean warm soil and protection for rice still in the ground.
Seed rot is another issue with the saturated soils. “For anything newly planted, we hope that it has a fungicide seed treatment on it, which will help it get through these conditions,” he said.
A little over 10 percent of the soybean crop has been planted, much of that acreage is south of Pine Bluff.
“The cool, wet weather is not good for just-planted seed to emerging soybean plants, but at least we won't see freezing conditions,” said Jeremy Ross, extension soybean agronomist. “The cooler conditions will delay emergence, which could enhance seedling diseases. Hopefully, most of the soybean crop planted at this point has a fungicide/insecticide seed treatment to help combat some of these soil pest problems.
“We still have a long ways to go with soybean planting. We just need some dry weather.”
Corn and sorghum
Kelley, who also looks after the state’s corn and sorghum crops, said the cold rain isn’t good for either. “Much of the early-planted corn has already had at least one light frost earlier in the season, so another round of cold will slow growth down even more. Emergence of corn or grain sorghum that was planted within the last week will be slowed, and while we hope stands will be okay, the full impact is still to be seen.”
Both Kelley and Extension Weed Scientist Bob Scott said that while fields are in need of weed control, “corn that is cold and stressed is more prone to herbicide injury.”
Read Scott’s post on cold, wet and herbicide injury here.
For more information about crops or gardening, visit www.uaex.edu or contact your county Extension office.