Off to a Good Start

Charles Johnson

11/4/2008

Get your cotton crop off to a vigorous start if you want to have the best possible finish. Agronomists agree that the first 40 days of growth is critical to push the crop to its optimum.

Your crop needs to be stress-free during that time for peak production. That means protecting it from seedling diseases, weeds and insects, as well as doing a good job of managing your soil nutrients and water.

If you’re growing crops in addition to cotton, that early management comes at a busy time. With cotton farmers in many areas now also paying attention to corn, soybeans, grain sorghum, rice, vegetables and other enterprises in the spring, managing cotton’s needs becomes more complex.

“A lot of things are competing for our time as cotton producers,” says Bill Robertson, National Cotton Council manager of agronomy, soils and physiology. “Many planted wheat this past season. They’re managing a harvest crew at the same time they’re getting the cotton crop started. They’re also watering corn then and planting soybeans. The labor pool is so limited that we have to think about how time impacts resources. Cot- ton farmers now have to take into account the demands for resources and how their crops and resources mesh.”

A bad start can leave you spinning your wheels all season long. “I’ve seen guys get into trouble with limited water, just to take one example,” Robertson says. “Once they get behind on a big pivot, they get further and further behind as the weeks go by because they just can’t catch up with demand. Also, the high demand for water on corn is right when they need to start cotton, so they get late on cotton. It gets complicated. You have to think through your logistics.”

Fertility focus. Springtime promises to be even more hectic than usual in 2009. High fertilizer prices mean more farmers will protect that investment with spring application, bypassing the fall option. That could be a good move, reducing chances of leaching or volatilization, says Tom Barber, Arkansas Extension cotton specialist.

“If I spend all those dollars on fertilizer, I want to know I’ve got it out there,” Barber says.

“One thing I’m focusing on is trying to put fertility out close to the time it’s needed so there’s less chance it will be lost. If you can make fall fertilizer applications and keep it there in the fields, fine. But we have to realize that it might cost us, and that cost is getting higher,” he adds.

High input costs will force farmers to pay closer attention to fertilizer.


“It’s absolutely critical to soil sample. You can’t afford not to,” Robertson says. “Fertilizer is too expensive to make assumptions, and you have to push that crop to maximize yield. My advice is to sample by soil types and productivity zones. Consultants are spending a lot of time this year working on fertilizing by productivity zones, and a lot of them have more than paid for their efforts by saving on fertilizer costs. We have to get smarter on sampling. If you’re not getting fertilizer out where you need it most, that’s going to hit you in the pocketbook right off. And if you put out too much fertilizer, at these prices you just can’t afford that. So it’s important to closely manage what you’re doing.

“If you’ve picked up a farm where the farmer let phosphorus and potassium slide, you have to work on it, and you have to know that you don’t build it back in a year,” Robertson explains.
Once you put fertilizer on the fields and get the planter rolling, there’s plenty you can do to protect the crop and get it off to a good start. You want healthy seedlings and strong roots, along with uniform stands and the right plant population.

All of that starts with good seedbed preparation and planting. Working fast is natural in the spring, but precision is more important than speed, agronomists say. If you’re going with reduced rates of ever-more-costly seed, timing and efficiency can save as much as 25% in seed and technology fees.

The publication “The First 40 Days,” published by the National Cotton Council and the Cotton Foundation, recommends uniformly spaced seeds planted into warm soil (temperatures of at least 65¢ªF) 4" deep for three consecutive days and adequate soil moisture. If planting into cooler soil, it’s necessary to increase the seeding rate. Plant population should be between 30,000 and 60,000 per acre. Go thinner than that and maturity will be delayed until later in the season.

It may pay to wait for optimum planting conditions. Delaying planting as much as four weeks might only delay flowering one week, some research indicates. Plant to a depth of 1" to 1½".

Seedling diseases like Rhizoctonia solani, Pythium and fusarium reduce U.S. cotton yield to the tune of about $200 million annually. Cool, wet soil puts young seedlings at greatest risk. That makes both planting in good soil conditions and seed treatment doubly important.

“All of the seed I plant is treated two or three ways for Rhizoctonia, Pythium and other soilborne organisms,” explains Craig Heinrich, who farms near Slaton, Texas. “As we’ve gone to seed with technology traits, that’s just how it comes, and that’s good. We want those seedlings to be protected.”

That all goes hand in hand with management of early season pests, including nematodes, mites, thrips and fleahoppers. At-planting systemic insecticides can help stop all of these pests. Agronomists do caution against what they term as a convenience application—over-the-top programs for pests such as aphids and plant bugs—since this approach can flare secondary insects. Coapplying insecticides with herbicides is also less than optimal because nozzles may not be the best way to target insect pests.

Preplant herbicide programs can help as well. Some insect populations can build on standing weeds. Tarnished plant bugs, for example, do well on marestail; spider mites thrive on pigweed. Scouting fields for insects is key, even in early season.

For nematodes, sampling is necessary to determine the extent of the infestation. Root knot, lance and reniform nematodes all cause problems in various parts of the Cotton Belt and
attack cotton differently. Post-harvest sampling can help you make zone maps for nematode management, cutting costs and pinpointing treatments. If you’re planting cotton in a field where nematodes are a problem, use seed treatment nematicides or preplant fumigants.

Crop rotation can also help manage nematodes. Growing other crops might help break the nematode cycle. Peanuts don’t host root knot, reniform or Columbia lance nematodes. Reniform nematodes don’t live on corn. Grain sorghum is not a host for reniform or sting nematodes. Many types of nematodes attack soybeans, but root knot-resistant soybean varieties are available.

“We don’t have the big questions about rotation we once did,” Robertson says. “People were apprehensive about planting cotton into corn stubble, but that’s not as big an issue as it was once thought to be. Rotation is certainly beneficial with herbicide programs, disease pressure and also the impact it has on fertility.”

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You can e-mail Charles Johnson at cjohnson@farmjournal.com.