Belzoni, Miss., farmer Willard Jack can think of lots of ways to consistently produce high yields. But if the fertility isn't right, he's just spinning his wheels.
“Fertility is one of the basics,” said Jack, who raises rice, cotton, corn and soybeans. “If it isn't right, then nothing you do the rest of the year matters — the variety you choose, whether you irrigated, your disease control, insect control.”
Jack didn't come to this conclusion by accident, having been raised on a farm operation “where my father was very much a stickler on soil fertility.”
The philosophy was re-enforced during his college days “because I had some good soil scientists train me. I learned that fertility is not something that you look at a year at a time. You have to plot where you are and plan where you're going.”
Jack and other growers who consistently get high yields have several things in common, according to fertility experts.
“They realize there are some variables they can't control, but fertility is one that they can,” said Lanny Ashlock of Cullum Seed and formerly Extension soybean specialist at the University of Arkansas. “They are definitely are not going to be found short in those areas that they can do something about.”
According to Cliff Snyder, southeast director of the Potash and Phosphate Institute, Conway, Ark. “They pay attention to the details. They like managing information in addition to managing the crop. And they want to know what the numbers mean.”
For Jack, the numbers start at 6.0. “I look at fertility in a little different light than some people,” he said. “We keep our soil at a neutral pH. It doesn't have to be right at 6.0. But lime is one of the basics. Until you get your lime right, there's no sense in going further. That's the first thing we work on in soil fertility.”
Another key is to soil test regularly, which Jack does. “From there, we go to our P and K. Depending on the soil test, we may get by with lower levels in certain crops.”
On the other hand, it doesn't hurt to have a little extra. “It's like money in the bank. If you put it in, you can draw it out when you need it. If you're going after top yields, you may not need it every year, but if it's there and the weather conditions are favorable, you can draw it out. So I try to keep both our P and K levels on the higher side.
“All that really means is that we carry a buck or so an acre in interest just to keep our levels up. We don't get into any trouble, and if the water and everything is available to make the crop, fertility is not our limiting factor.”
Jack also considers fertility somewhat of a hedge against weather extremes. “No doubt about it. If you eliminate any fertility deficiencies, that's just one more stress that you're taking away. I'm not comfortable saying that if it's dry, a little more will help. It sure won't hurt, and if you do get good growing conditions, you can make a better crop.”
Holly Grove, Ark., farmer Tim Smith calls fertility, “the cheapest insurance we can buy. The better your fertility, the better the plant is and the better it can handle stress.”
Like many growers these days, Smith is concerned about reducing costs and becoming a more-efficient farmer. The conversion to no-till has created some opportunities to do just that.
“Since I'm no-tilling and planting right back on those same rows year after year, I've gone to banding all my fertilizer and placing it where I want it,” said Smith, who is about 70 percent no-till. “If there's any carryover to the next year, I've got the plant's root system going right through it again.”
On corn and soybeans, at planting “we'll place our phosphate right in the furrow. Then 2 inches off the row and 2 inches deep, I'm placing my potash, and on corn, a little nitrogen at planting.
“On my soybeans, I'll come back on my second shot of Roundup, and I'll foliar-feed with 2 or 3 gallons of the potash.”
Smith has also changed to a fertilizer product that's not as tough on the earthworms and microorganisms which thrive in no-till. “I use a product that comes out of Lansing, Mich., called liquid culture fertilizer. It has no salt, which really protects the organic life, the seed and the roots, and it has a neutral pH.
It took Walnut Ridge, Ark., farmer Rob Roberts farmer a few years to appreciate the value of fertility in his soybean crop.
Roberts, who farms about 820 acres, divided evenly between rice and soybeans, had always soil sampled in front of rice and followed university recommendations.
“We never really did anything in front of the beans, and I guess that goes back to the time when beans were treated like a stepchild. But that's changed over the last 10 years.”
Roberts has been grading his land for irrigating and draining rice. “When we got it all land-formed, we started irrigating beans. But we weren't seeing the yield jump that we were expecting. It was better, but it wasn't what we thought we could do with the setup we had.
“We realized we were giving the plant plenty of water, but we weren't putting any fertilizer out in front of the beans at that time.
“When you soil sample in front of your rice, the university gives you the following year's recommendations for soybeans. So we started putting out a minimal amount of potash out in front of the beans.
“We gradually increased the amount of fertilizer and now we're seeing the yield increases. It also has a lot to do with the varieties, but we've seen a tremendous yield increase.
“When I came out of college in the late 1980s, we were probably in the mid- to upper-30s on our irrigated ground,” Roberts said. “We in the lower- to mid-60s now. That's a tremendous jump. But it's a combination of things — better irrigation practices, drainage and going from almost no preplant fertilizer to 0-45-90 in front of all our bean ground.”
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