Late-planted crops this spring and extreme weather through the summer have played havoc with corn and soybeans in many U.S. regions. This has created such problems as increased pest pressure, ear rot, lodging and other challenges. Consequently, scouting fields until harvest can greatly benefit growers, says Chuck Bremer, Pioneer agronomy information manager. Such scouting can lead to better harvest management and provide insights into 2012 seed decisions.
"Each region of the United States has experienced some type of stress this growing season," Bremer notes. "For some, that means a late start to planting due to excessive rains, while others experienced stress in the form of drought."
Late-Season Corn Management
"A late planting start, like those across the Northern and Eastern United States, invites the threat of frost before reaching black layer," Bremer says. "Should this occur, growers could consider using their crop for high-moisture corn or silage for livestock."
Drought conditions plagued areas across the South and Southeastern United States. Growers in these areas should watch for Aspergillus flavus and Fusarium ear rots.
"The best way to avoid load rejection at the elevator due to Aspergillus flavus is to adjust the combine settings," Bremer says. "If growers suspect the disease, they should adjust their combines to reduce grain cracking. This includes adjusting the cylinders, turning up the air and adjusting the screens."
If the crop goes into feed, Fusarium can cause complications on the backend. The disease can continue to grow in storage following harvest and be can be toxic to livestock. Continuous monitoring is necessary.
Growers could anticipate lodging in areas where crops were planted in less than optimum conditions and encountered drought stress. "Growers should pinch their stalks," Bremer says. "If the plant shows stress, growers need to schedule those fields for early harvest, if possible."
Another issue that continues to expand is Goss's wilt. The disease originated in Nebraska and continues to expand into Iowa, Wisconsin, Illinois and surrounding states. Plants with this disease commonly have lesions with wavy margins. The margins of lesions have a water-soaked appearance with black flecks that cannot be rubbed off the plant tissue. Growers encountering the disease should consider a hybrid with Goss's wilt tolerance next season.
Late-Season Soybean Management
The Northern United States-- west of Lake Michigan-- has the potential to see soybean aphids, as reports of the pest are surfacing. The threshold for an application is 250 aphids per plant up to the R5 stage.
Other risks for soybeans include spider mites. Indiana, Illinois, Missouri, Iowa and some areas across the North are encountering this pest. Double-crop or late-planted soybeans have greater potential to host spider mites. Soybeans planted early are past the peak feeding time and therefore are less susceptible to spider mites.
"They thrive in hot, dry weather," Bremer says. "Growers should scout the edges and corners of fields first, shaking the bottom leaves over a sheet of white paper. If a grower sees 'moving dirt' they may have spider mites."
As the season progresses, growers in Illinois and Indiana should scout for sudden death syndrome (SDS) due to rains early in the growing season.
"SDS will show up in fields with prime soils. The plant will have yellowing and defoliation in the upper leaves," Bremer says. "Typically the disease is confined to an area and will not likely take an entire field."
If a grower sees SDS in a field, he or she should consider choosing a variety with high tolerance ratings to the disease.
"Each growing season offers growers the opportunity to reflect and learn lessons," Bremer says. "It's a good time to gather data and use it to make informed seed purchases for the 2012 growing season."
You can get more information on pest and disease management by clicking here. www.pioneer.com/agronomy For more crop information you can visit Pioneer’s and DuPont’s websites. www.pioneer.com/products www.dupont.com.