“I like to remind farmers two of their highest returns on investment are scouting and crunching numbers,” says David Widmar, senior research associate at Purdue University. Scouting protects profits. For example, catching northern corn leaf blight early can save up to 30% of your yield.
It’s important to understand the severity and spread of a disease to make the right cost-saving decisions about fungicide use. You don’t need to treat acres without problems, but treating the right acres can save yield.
The location of the disease on the plant could mean the difference between spraying a fungicide or holding off. “You can have a disease like northern corn leaf blight on leaves below the ear leaf and not treat, especially if conditions aren’t conducive for spreading,” says Damon Smith, University of Wisconsin assistant professor of field crop pathology. “But only 10% of northern corn leaf blight damage on a corn ear leaf can result in some yield loss.”
Timely fungicide application can save 4 bu. to 15 bu. per acre, according to Iowa State University research. If you see fungal disease on the third leaf below the ear leaf or higher on 50% of corn plants at tassel, consider a fungicide application, crop experts say.
“We’ve had a hard time justifying [fungicide expense this year],” Smith says. “We’ve looked at the probability of return on investment—it’s only 60% you’ll get a positive return when disease is active with corn between $3 and $4.” That doesn’t mean you should avoid spraying, just use more scrutiny. As you make these decisions, keep your crop budget up to date. “We make budgets but don’t revisit them,” says Widmar, also a partner with Agricultural Economic Insights. July is a good time for you to revisit your marketing plan. Specifically:
- Update budgets to reflect reality
- Know cost of production to date
- Scout to learn real yield potential
- Sell based on the above factors
“You have to lock in a $4 floor for corn,” Utterback says. Summer, mid-May to July is the best time to sell corn. Soybeans tend to hit their high in July and August, he says.