Mississippi producers and consultants recently received late-season updates and recommendations from Mississippi State University scientists as the 2014 growing season nears its end.
About 40 people toured fields at the Delta Research and Extension Center in Stoneville Wednesday, examining row crops and gaining information on late-season management.
Jeff Johnson, head of the Stoneville center, said the event allowed MSU Extension Service and Mississippi Agricultural and Forestry Experiment Station personnel to directly extend the knowledge of the university to the people of the state.
“The producers are doing everything they can to finish this crop year strong,” Johnson said. “We held this field day to bring the latest information from our specialists to help as growers make decisions regarding their crops as harvest nears.”
Peanuts, corn, rice, soybeans, sorghum and cotton spent time in the spotlight as specialists gave updates on current management issues.
Disease pressure …
Jason Sarver, Extension peanut specialist, said many peanuts this year are being treated for Sclerotium rolfsii, which is commonly called white mold but is more correctly called stem rot or southern blight. Careful crop rotation reduces this problem.
“We want to use peanuts, but we want them in a good rotation,” Sarver said. “Two years between peanut crops is good, but three years is better. From a disease control perspective, peanuts rotate well with corn or cotton but not with soybeans.”
The white sugarcane aphid is wreaking havoc with the state’s grain sorghum this year. Extension and Experiment Station entomologist Jeff Gore said Mississippi just received approval for a treatment process in which a third insecticide application can be made to control this pest.
Tom Allen, Extension plant pathologist, said soybean rust has not been seen in the state.
“Our neighboring states have picked up a little bit of soybean rust,” he said. “We’ll continue to monitor the situation because we maintained a conducive environment for soybean rust development this summer.”
Crop Maturity …
Erick Larson, Extension grain crops agronomist, said growers need to be able to judge when a crop reaches maturity and understand grain drying to optimize efficiency and minimize harvest losses.
“Nearly all sorghum is infested with white sugarcane aphids, and this new pest secretes a sticky honey dew that can clog combines and severely restrict harvest,” Larson said. “Growers must be able to identify the appropriate growth stage to apply harvest-aid pesticides to enhance harvest without sacrificing grain quality and yield.”
Both corn and sorghum reach maturity well before their grain moisture is safe for long-term storage. Growers must factor grain moisture, potential harvest losses and their harvest capacity to develop a strategy to optimize efficiency and profit, particularly since market prices are much lower this year.
Wayne Ebelhar, Experiment Station soil fertility researcher, said corn that is too dry also loses grains, and that adds up to a profit loss.
“At 15 percent moisture, some kernels will fly off when they hit the metal of the combine,” Ebelhar said. “At 18 to 20 percent moisture, very few fall off, but if you drop corn at 12 percent moisture, kernels will scatter everywhere.”
Ebelhar suggested that growers check to make sure combines are set up correctly to prevent corn from being lost during harvest.
Darrin Dodds, Extension cotton specialist, said cotton is approaching its last effective bloom date in some areas of the state. Depending on location, that date is Aug. 18 in the north Delta to Aug. 25 in the south Delta.
“Whatever bloom is on the plant at the last effective bloom date is the one you have a good chance of putting in the picker basket,” Dodds said.
Dodds said the correct application of growth regulators is related to cotton boll retention.
“At this point in the season, you don’t need any more vertical growth on the plants,” Dodds said. “There are a number of reasons to keep height under control. One is to allow the penetration of insecticides to the plant, and another is for harvest efficiency. You can go through shorter cotton with a picker faster than tall, rank cotton.”
Soil nutrition …
Mississippi producers have had very successful, high-yielding crops in recent years. Ebelhar said these record yields mean producers should monitor soil nutrition carefully.
“When you look at how much phosphorus and potassium we’re taking out of the soils with these high yields, you understand why we need to start soil testing more frequently,” he said. “You can only take money out of the bank so long before you have to put something back.”
One way to manage soil nutrition is to leave crop residue on the field, he said.
Weed control …
Crop residues left on field surfaces also help with weed control, said Jason Bond, Experiment Station weed scientist.
“We can have about two months of summer weather after harvest until the first frost to have to deal with weeds,” Bond said. “There are not a lot of herbicide options for application after harvest.”
Bond recommended producers leave shredded corn stalks lying on the ground for as long as possible to provide a mulch covering, which prevents weed seeds from germinating.
Bobby Golden, Experiment Station agronomist, urged producers to control weeds after harvest this year in fields that will be planted to rice next year.
“Keep grasses down because they’ll be hard to control in next year’s rice,” Golden said.
Irrigation termination …
Mid-August is near the time when most producers begin to drain rice fields.
“In Mississippi, we typically drain rice when two-thirds of the panicle has turned straw-colored,” Golden said. “With a lot of uneven heading in the state, it may be difficult to make drain timing decisions this year.”
For traditional row crops, growers typically must evaluate soil moisture conditions to know when to end irrigation for the year. With this summer’s frequent rains, “you might not have control of that this year,” said Lyle Pringle, Experiment Station irrigation researcher.
He and Jason Krutz, Extension irrigation specialist, urged growers to use soil moisture sensors to determine the water content of the soil. Producers know when to irrigate for the last time when they combine soil moisture information with existing data on how much water a particular crop needs at a given point in its maturity.
Krutz said producers who haven’t yet begun to use a computerized hole-selection tool with their polypipe irrigation should gather the data now and set up their fields over the winter to increase irrigation efficiency next year.