Corn and soybean growers in the Eastern North Carolina coastal plain have suffered through two consecutive seasons of excessive rain in 2013 and 2014.
Are there any lessons to be learned from these exceptional weather situations?
Ron Heiniger, North Carolina Extension corn specialist, has a couple to share relative to corn.
“The start and finish of the corn crop are the most important parts of the season in a wet year,” he says. “In a dry year, the mid-season may be a little more important.”
But to do well in a wet season, it’s very important to get the crop off to a good start. “It is so difficult to overcome a poor stand,” he says. “Skips at planting will follow you all season.”
Here are a couple of things to remember, Heiniger says:
• You don’t want corn plants that come up a day after the rest. “They will almost certainly be ‘weeds’. If they produce an ear at all, that ear will be only a third the size of ears on the other plants. The other plants will outcompete it for resources.”
• Be sure to get equal spacing of seed down the row, calibrate your planter carefully, and make sure it’s in good condition.
“One problem we sometimes see is too much pressure on the press wheel, which can cause compaction,” Heiniger says. “Or the hopper box can bounce up in the field, and you can get seed planted at different depths.”
At the end of a rainy season, he says, disease control is crucial. One way to do that is to keep corn leaves green as long as you can.
Rains affected corn yield
How rainy was it? The Gardner family in Macclesfield, N.C., had nearly as much rain this season as there was in 2013.
“We had quite a bit of rain this year,” says Kevin Gardner. “It affected our corn yield. The corn wasn’t averaging what I was hoping for.”
As in 2013, there were moments when Gardner remembered the old saying, “A dry year will scare you, but a wet year might ruin you.”
The yield impact wasn’t that bad, however — or didn’t appear to be in late September. “I think it might be a decent crop if it doesn’t get washed out by more rain,” he said then.
Gardner farms with his father, Joe, uncles, Edward and John, and cousin, Adam. In addition to corn and soybeans, they grow cotton, tobacco and some wheat.
Ripping soybean land
A good start helped Michael Gregory of Four Oaks, N.C., get a satisfactory soybean crop despite all the water.
In light of the wet 2013, he made a change in his land preparation.
Before planting, he used a V-ripper to break up the hardpan. “This helped increase yield this season, and it should also help in the following years,” he says.
Other changes were use of a foliar fertilizer and a mix of Roundup and Dual as a postemerge treatment to hold back pigweeds.
The declining price of soybeans has been a problem, and he has had to economize as much as he could on production expense.
“We try to keep costs down, but you can turn your soybeans into a summertime cover crop if you don’t put enough into it.”
Both Gregory and Gardner grow tobacco, and they derive a side benefit from it: pigweed control.
“The herbicides used in tobacco — especially Spartan and Command — really help with pigweed in whatever the subsequent crop is,” says Matthew Vann, North Carolina Extension tobacco specialist.
Now some growers are wondering if it would make sense to swap land with a tobacco grower as a means of controlling pigweed in their corn or soybeans.
“If you can find a good fit for it, it might be worth a try,” says Vann. “It could be a win-win situation for both sides. The grain grower would get a lower level of pigweed in his next crop, while the tobacco grower would probably get land with very little soilborne black shank or Granville wilt, two very damaging diseases on tobacco.”
Tobacco usually involves the use of some hand labor, and that provides an opportunity for roguing pigweed in the field.
And if you are hand weeding pigweed, Vann recommends that you pull the weeds from the soil before seed set occurs.
“Once weed seed develop, you can actually spread them by hand removal.” He also recommends that you remove the pulled weeds from the field. “In rare situations, amaranth species have been known to ‘re-root’ when left on the soil surface.”
Tillage can help
Deep tillage of tobacco has also been shown to reduce pigweed, both in the current crop and in subsequent ones.
“Deep tillage with a moldboard plow will invert the top six to eight inches of the soil profile and bury weed seed at a depth that germination can’t occur,” Vann says. “But it is advisable to leave the soil profile intact for at least 36 months post-deep tillage to reduce seed viability.”
Minimum tillage might be a good idea in order to let pigweed die a slow death.
Gregory tries to plant soybeans behind tobacco whenever he can for the weed control it provides, he says.
“I can pull pigweed in tobacco cheaper than I can spray it in soybeans, unless there is an awful lot of it,” he says. “Our workers can pull it before it gets big enough to seed.”
He uses Spartan and Command. But he doesn’t subscribe to deep tillage. “We might flip seed upside down. You could bring six-inch deep seed up to the top.”