Last year was the slowest, wettest, most frustrating harvest across the Corn Belt in 35 years. Farmers in North and South Dakota tried to finish harvesting corn in January with snow still on the ground. This fall, parts of the Corn Belt, particularly the southern and central sections, will likely see the fastest harvest ever.
What that means is that some practices that worked well in 2009 worked well this year and some didn't, and vice-versa. Last year Dave Nanda, a crops consultant now with Seed Consultants, Washington Court House, House, inspected a field of corn in late June and cautioned the farmer to be ready to apply fungicide. He was starting to see gray leaf spot on lower leaves. However, then it turned cool and wet for about five weeks. When Nanda, Indianapoluis, returned in late July, the disease had made virtually no progress. The farmer, taking Nanda's advice, didn't spray, and was later happy he didn't. Although there were no comparison strips, compared to the same hybrid raised close by, he's convinced a fungicide would not have boosted yield, at least not enough to justify paying for it.
This year was the opposite. Instead of conditions becoming less conducive for disease, in some areas they became more conducive as the season unfolded. Lots of heat and humidity featured such rouges as gray leaf spot and northern corn leaf blight. While northern corn leaf blight typically is worse in the northern half of Indiana, for example, it was found as far south as Jefferson County this year.
One of Greg Knewbuhler's clients in Allen County applied a fungicide and left a check strip. His crop was already showing many signs of northern corn leaf blight and gray leaf spot when Kneubuhler checked it at pollination time. Since the farmer had ground –application equipment, he was able to spray the field, yet leave a check strip.
The combine revealed a 30-bushel per acre difference in treated over untreated Kneubuhler cautions, however, that this was an unusual situation. Two diseases ganged up on the corn early. Plus it's probable that the hybrid was susceptible to the diseases in the first place.
Bottom line is that just because a fungicide increased yield 30 bushels per acre in one field one year, doesn't mean the pay-off will be stat strong every year. "It says what happened this year, not what happens every year. Next year may be a whole different story. In fact, if the last few years are any indication, odds favor next year not anything like this year in terms of precipitation amounts or temperatures.