When Weldon, N.C., Crop Consultant Daniel Fowler first saw the lush, green crops in an area called Mush Island, he saw an opportunity to make a good thing better, and he’s done it.

Working with Weldon, N.C., farmer Ellis Taylor, Fowler has developed a set of GPS-driven, computer generated maps that provide data that allows the North Carolina farmer to put varying rates of fertilizer exactly where it’s needed most.

Standing in the middle of a 750 acre cotton field on Mush Island, which is adjacent to the Roanoke River near Weldon, Fowler explains everything on the farm is zone sampled. He looks for crop response, clay galls, sandy spots in the soil and any other problem areas, and those are the first areas that are zoned out.

Then, he looks for soil types and anything in aerial photography that shows differences in plant growth is his starting point for creating zones. In the 750 acre plot of land, he says, there will be an average of about three acres per sample.

“Compared to a 2.5 acre grid, I feel like I can have a little larger average sample size, because I’m breaking up the variability in the soil,” he says. All the topography maps are generated using GPS technology.

We take soil samples and take soil data for analysis. Then, we look at the growers planned crop for that field in the next growing season, and we determine fertilizer rates. On Taylor’s Mush Island farm, Fowler says things got a little complicated because of some new irrigation equipment.

The grower did not want to put nitrogen through the pivot. His thinking is fertigating would deteriorate the irrigation equipment and reduce the number of years he could use it efficiently.

However, he did want to put a different rate of nitrogen under the pivots and outside the pivots. The combination of rates under and outside the pivots created a challenge that Fowler and Taylor have converted into an opportunity to maximize fertilizer use and profits.

“We had a two-fold challenge, Taylor says. “We were trying to figure out how to put more nitrogen on corn last year under a new 400 acre irrigation pivot. And, we wanted to shoot for 200 plus bushels per acre under the pivot and 120-140 on dryland.”

Taylor says he didn’t want to over-apply nitrogen on the dryland corn. “In the past, growers overcame the problem by running nitrogen through the pivot, but I just wasn’t comfortable doing that. So, we were looking for a way to solve that problem.

Near waterway

“And, we’re right beside a river, and I like to have nitrogen under the ground, not on it. I’d seen an article in Farm Press where some growers had converted the KBH nitrogen rig over to a variable rate rig. So, I approached Daniel to look into some ways to do something similar on our farm,” Taylor says.

“We went variable rate with the fertilizer spreader truck. Ellis takes his computer out of the spreader truck and puts into his tractor. He has rigged up a pump to allow him to variable rate liquid nitrogen. “We don’t get much triple super(triple super phosphate, analysis, 0-45-0, is highly effective in eliminating phosphorus deficiencies in most crops, under most soil conditions) in our area. The most common fertilizer blend used in the area is DAP,” Fowler explains.

DAP fertilizer is a combination of phosphate rock and sulfuric acid, which is combined to form phosphoric acid, which is then mixed with ammonia to produce DAP, a dry granular product.  Typical DAP blends are composed of 46 percent phosphorus and 18 percent nitrogen.

“In areas in which we need phosphorous beyond what the soil gets with a starter fertilizer, we apply DAP. In the past, the nitrogen component has been in excess. Now, we are taking some of that N and putting less in the top-dress in zones that need more nitrogen. If we have a sandy spot in the field, we are able to add some nitrogen to that area.

“Conversely, Mush Island is prone to producing too much growth. In areas of the field in which we are prone to get more rank growth, we can take N away from that zone,” Fowler explains.

All these benefits came about because the grower wanted to put more nitrogen under his pivot than outside his pivot. Technology provided an outlet for him to do that and more.

“I came out here with a hand-held computer and marked the center of the pivot to the outside of the pivot and under the end-row gun. He told me how many feet the end-gun would throw water. So, we are now able to put a target rate of nitrogen for the season under the pivot, a target rate of nitrogen under the end-row gun and a target rate outside the pivot,” Fowler says.

“I’m fortunate to be working with a grower like Ellis. He’s very technology oriented and always wants to try new things that will make his operation run a little smoother. I work with him on all his crops,” he adds.

“Daniel is giving me a prescription file for fertilizer. My family has been in the cotton ginning and fertilizer business for a long time, so I have a fertilizer house.

Fertilize a year ahead

“The prescription file allows me to buy my fertilizer a year ahead, if I can find a good price. But, I was guessing at what blend I needed. Now, we can dial in what blends we need and it really allows us to farm a big farm like we used to farm a few acres,” Taylor says.

The variable rate fertilizer process for 2012 has already begun. Fowler began soil sampling immediately after Taylor harvested his corn crop. As soon as cotton was picked, he came in and sampled cotton land. By the time spring planting comes, the grower will know almost exactly how much nitrogen he will be applying in which fields.

“The big advantage to using zone sampling and variable rate fertilizer application is it allows the grower to put more nutrients where they need to be and we are doing it cheaper,” Fowler says.

The net result is less money spent on fertilizer, but that’s not the goal the only goal. In some cases growers may spend more money using variable rate technology, but they get the maximum benefit from the fertilizer dollars they are spending,” he adds.

“There are some growers who look at variable rate as a way to save fertilizer dollars, and I think that is a short-term way to look at it. If you can save a few dollars, use the technology, improve your problem areas, it is a great opportunity to dissect a farm and go back to farming large acreages much like we used to farm small acreages,” Fowler says.

The North Carolina consultant got his start after graduating with a degree in agronomy from North Carolina State University. He worked for then North Carolina Cotton Consultant Larry Pendleton in Scotland Neck — in the heart of Carolina cotton country.

In 2001, Pendleton took another professional route in agriculture, which started Fowler and three other crop consultants (Mary Wilkes, Grant Stayton and Bert James) on their professional careers. Fowler started out on his own, moving his operation from Scotland Neck to Weldon, N.C.

In addition to cotton, Fowler works with corn, soybeans, peanuts and tobacco. This year, or at least the end of it has been a tough one, he says. Hurricane Irene and Tropical Storm Lee combined to drop heavy and almost continuous rain on the area. The heavy late-season rainfall and often flooding, combined with damage from wind from both storms, created a mess with crops this year, he says.

rroberson@farmpress.com