What is in this article?:
- Off-season talks center on continuous corn
- Not the only issue
• Many discussions will take place this winter about the widespread yield problems with continuous corn in 2011.
• With corn seed production hit hard in some areas, possible shortages of some hybrids have been reported.
Not the only issue
“Soil management was certainly not the only issue, but we might at least keep in mind that breaking down soils with tillage almost to the point they’re ready to plant in the fall might not be that helpful come spring,” he said.
“It’s appropriate to till this fall to break up compaction again in many fields, but we should always ask ourselves if the second trip this fall is necessary.”
Dry conditions in the second half of the season usually result in less nitrogen uptake by the crop, and in accumulation of some nitrogen in the form of nitrate in the upper soil layers.
Normal precipitation between now and spring will allow much of this nitrate to move down, and some will exit through tile. But in fields where soils are dry now, where corn yields this year were lower than normal, and where we will follow corn this year with corn next year, he said growers might want to consider taking soil samples before applying nitrogen next spring.
With corn seed production hit hard in some areas, possible shortages of some hybrids have been reported. There are also reports that some winter production in South America was planted late, so seed could be late arriving next spring.
Soybean yields are not as high across Illinois as they were in 2010. The average yield is now projected at 46 bushels per acre, down from last year’s 51.5, which was an Illinois record. But yields are very high again in some areas, especially in northwestern Illinois, he said.
“We’ve heard of a few cases where the second year of low continuous corn yields has some people considering putting soybeans back into some fields in 2012, after a number of years in continuous corn,” Nafziger said.
“Having corn prices more than half the price of soybeans per bushel still favors corn at the moment, and it’s not unreasonable to hope for better corn following corn yields in 2012 than some of us had this year.”
Soybeans following five or more years of corn in a field typically yield somewhat better than soybeans in a corn-soybean rotation. He reminded growers to get soybean seed inoculated if corn has been in the field for five years or more.
Finally, a quick look at U of I data on corn plant populations reconfirms that stress conditions are not conducive to getting responses to population increases up to high levels. But high populations did not produce many of the disastrous yield losses like some saw last year.
“You might want to consider raising populations if they’re still not high enough, but don’t figure on increasing them much past the mid- to upper 30,000 range,” Nafziger said.
For more information, read The Bulletin online http://bulletin.ipm.illinois.edu/.