Maybe you're one of the farmers who hasn't seen a yield reduction when you grow corn after corn. But if you're like many others, and nearly all university researchers who take a close look at rotation corn after soybeans vs. continuous corn, you probably see a yield hit in the year when corn follows corn.
A year ago many figured it was worth it, even if there was a yield drag to continuous corn, since corn prices were skyrocketing and the direction for soybean prices were uncertain. Corn prices are still high, but so are soybean prices. Throw in prime wheat prices, and there could be pressure to move back toward less corn after corn in Indiana for '08. Market analysts say market forces still at work will finally determine which crop buys back the most acres for '08.
Meanwhile, even if you've got one field you're going back on corn after corn with, Purdue University's Extension corn specialist Bob Nielsen and his co-workers have assembled a set of suggestions they believe can help reduce potential yield slip in corn after corn situations. They've produced a new publication. Ask your Extension agent for it, or access it directly anytime on the Web. Nielsen maintains his own Web site which highlights corn production. Find the article that should help you reduce yield losses in corn after corn at: www.kingcorn.org/news/timeless/CornCorn.html.
One thing any hybrid you plant in a corn after corn situation will need is good seedling vigor, agronomists say. It will also need a good disease package. No-till corn after corn tends to lag even further behind in yield potential, and it's not a favorite system in Nielsen's book. But if you're going to do it, or don't have any choice because the field where you're planting corn after corn is highly erodible and no-till is required to participate in USDA programs, he offers a suggestion.
"That is definitely a situation where it would pay to scout during the season, and be prepared to apply a fungicide if necessary," the corn specialist says. While many people applied Headline fungicide last season in all kinds of tillage systems, results were inconsistent. However, no-till corn after corn fields are more suspect to disease, because several disease-causing organisms can overwinter in the corn stalk residue.
Whether that turns into infection or not will depend upon weather patterns next season. If conditions are right for leaf diseases to get started early, and march onto the ear leaf by pollination time, it's a problem that could demand action. That's when spraying a fungicide can become an economic plus.
The problem can be compounded if you don't start with a hybrid with a good disease-resistance package, the specialist notes. So make double sure you know all you need to know about hybrids you're going to plant in corn after corn situations.