In a grower research trial in Bancroft, Wisc., and a study conducted at the University of Georgia (UGA), Nitamin^®Steady-Delivery® liquid fertilizer from Georgia-Pacific increased marketable carrot yield and improved harvest efficiency when compared to the local grower standard programs of fertilizing with UAN or ammonium nitrate, respectively. The carrots that were fertilized with Nitamin liquid fertilizer also produced fewer splits and culls, resulting in increased crop quality.

Nitamin, developed by scientists at Georgia-Pacific, is a slowly-available nitrogen source that delivers the Optimal Nitrogen Diet™ to crops. Unlike commonly used quick-release fertilizers that convert most of their nitrogen to useable forms within the first few weeks, the patented NitaminSteady-Delivery fertilizers deliver nitrogen to crops at a rate that they can effectively utilize throughout the growing cycle, while minimizing nitrogen loss through leaching and volatilization.

In the Wisconsin grower study conducted on Patrykus Farms, owned by Mr. Dave Beggs in Bancroft, Wisc., with assistance fromTH Agri-Chemicals and Royster-Clark, a mid-season application of Nitamin liquid resulted in a yield increase of three tons per acre and a higher percentage of marketable carrots, compared to the standard UAN application. On August 3, 2005, Nitamin liquid was applied to a total of 90 acres through the pivot irrigation system at a rate of 67 lb. of N/acre. An adjacent field received 32% UAN solution applied at an equivalent rate. Prior to the August application, both plots received a total of 80 lb. N/acre from various quick-release N sources. No additional nitrogen was applied after the final sidedress application. Differences between treatments were observed within the first few weeks after the initial application. The carrots in the Nitamin treated fields had greener foliage and larger top growth (photo 1). By early September, the canopy in the Nitamin field had completely filled in the rows (photo 2) and the carrot roots were visibly thicker (photo 3). Because the carrots in the Nitamin field were healthier, fewer fungicide applications were required.

Photo 2. Grower standard fertilizer program on left and Nitamin program on right. Notice that Nitamin plants are fuller and bushier and the larger tops fill in the middle row area whereas bare soil can be seen with the grower fertilizer program. Also notice plant height differences in both photos.

Photo 3. Nitamin treated carrots are positioned on the right and the grower standard treatment on the left. Notice larger size vegetative growth and thicker roots in Nitaminfertilized carrots. This field was approximately three weeks from harvest.

Differences between treatments were observed within the first few weeks after the initial application. The carrots in the Nitamin treated fields had greener foliage and larger top growth (photo 1). By early September, the canopy in the Nitamin field had completely filled in the rows (photo 2) and the carrot roots were visibly thicker (photo 3). Because the carrots in the Nitamin field were healthier, fewer fungicide applications were required.

According to Mr. Beggs, estimated mechanical harvester loss was reduced by 10% to 15% with the use of Nitamin because the stronger tops allowed more carrots to be pulled from the ground. The Nitamin carrots were also more uniform in size and length.

Upon delivery to the processor, the carrots from each field were graded to determine the amount of “useable” and “waste” carrots. Evaluations from three separate truck loads showed that carrots from the Nitamin field had an average of 3.8% more useable carrots. (See figure 1 below.) If the industry average yield was 40 tons/acre, this 3.8% increase would result in 1.5 tons more useable carrots per acre.

“I normally use tissue sampling to determine when to apply the fertilizer the plant needs at a specific stage of growth,” Mr. Beggs says. “The drawback is that by the time the tissue sample tests return, I have lost the opportune time to apply the necessary fertilizer on my crops. In carrots, too much fertilizer can cause growth cracks or too much top growth. Too little fertilizer can cause poor top growth, disease and poor uniformity. The side effect of having too little or too much fertilizer directly influences my crop yields.”

Beggs added, “When we harvested the carrots, the ones treated with Nitaminfar exceeded my expectations. My plants were healthier, so my fungicide applications decreased. Not only was I able to get savings in my chemical/fertilizer inputs but I had a 3% increase in my useable product ratio. Next season, I may put down lessseed per acre since the harvest potential with Nitamin is greater than the standard program.”

Tom Vander Heiden, marketing manager with TH Agri-Chemicals, routinely monitored the trial. Vander Heiden said,“Many growers in this region harvest from August through November, so the tops could endure at least two to three hard frosts before harvest. Having a healthy carrot canopy is essential for mechanical harvesting since the plants are pulled rather than dug from the soil.”

Jim Wargo, the research agronomist with Georgia-Pacific noted that,“Weak top growth means fewer carrots make it out of the field, resulting in more waste and lower harvestable yield. In order to make it in the processing market, a grower must have a high plant population of large size carrots with tops strong enough to withstand pulling.” (See photo 3.)

The study at the University of Georgia, Coastal Plain Experiment Station in Tifton, led by Extension Horticulturist Dr. Terry Kelley, showed that applying Nitamin liquid in three equal applications during the growing season resulted in a significant yield improvement over the same amount of ammonium nitrate applied in five split applications. Both treatments had a total of 150 lb. N applied over the growing season. Nitamin treatments received one-third of the total N at planting (AP) in October, with the remaining two-thirds applied in January and March. Ammonium nitrate treatments were applied on the same schedule with additional applications in December and April. Total yield was similar for split applications of Nitamin and ammonium nitrate, but Nitamin resulted in a statistically significant increase in marketable yield. (See figure 2 below.)

The carrots were grown over the winter months, and applying all of the Nitamin at planting was not as effective as split Nitamin applications due to the long growing season. However, Nitamin applied all at planting produced marketable yields equivalent to four sidedress applications of ammonium nitrate from December to April. The lower percentage of marketable yield with ammonium nitrate was due to an increased amount of split carrots in that treatment. The steady supply of nitrogen from Nitamin resulted in less splitting, which is typically associated with growth spurts that occur from fluctuations in nitrogen availability.

According to Dr. Kelley, “Nitaminhas the potential to save growers trips across the field and provide fertilizer to the plant during times when field conditions may not allow for the most timely application of fertilizer in a standard grower program.”

Additionally, Jim Wargo said, “Results from the UGA and Wisconsincarrot trials suggest that Nitamin can be used as the sole nitrogen source throughout the season or as part of the grower’s standard nitrogen program. In either, Nitamin allows growers to guard against problems associated with season-long spoon feeding using quick-release fertilizers.”

Experimental Details

Wisconsin grower trial: Grower Dave Beggs conducted a carrot trial on the variety “Enterprise” at Patrykus Farms in Bancroft, Wisconsin. The carrots were commercially grown for processing. Planting took place from June 1 through June 5, 2005. The treatments included a grower standard and Nitamin liquid used in combination with the grower standard. The Nitamin and grower standard plots received the same fertilizer program until early August, at which time the final sidedress application was made. On August 3, 2005, 67 lb. of N from Nitamin liquid was applied to a total of 90 acres through the pivot irrigation system and compared to 32% UAN applied at an equivalent rate in an adjacent field. No additional nitrogen was applied after the August application. Prior to the final sidedress, all fields were treated the same and had received a total of 80 lb. of N/acre from various quick release N sources. Irrigation was applied every other day during the summer to maintain adequate soil moisture. All other practices were the same for both treatments throughout the season. The carrots in the experimental fields were machine harvested from October 25 through November 15.

University of Georgia: Apache carrot seeds were machine planted in October 2004 in Tifton loamy sand. The plot design was a complete block with four replicates per treatment. Plots were 6’ x 18’ and consisted of three rows in each plot. Treatments included ammonium nitrate (AN) and Nitamin liquid applied at 150 lb. N/acre. Nitamin was applied either all at planting (AP) or in three split applications with one-third applied AP and the remaining two-thirds applied in January and March. AN was applied in five equal applications with 35 lb. N applied AP. Additional applications were made in December, January, March, and April. Ten feet of the middle row was harvested on May 9 and 10, 2005 for yield evaluations.

Georgia-Pacific Resins, Inc. (GPRI) is a wholly owned subsidiary of Georgia-Pacific Corp., and is a market leader in chemical products for the paper, pulp and building products industries, as well as other industrial manufacturing processes. GPRI has been a major raw material supplier to leading fertilizer producers for over 20 years and has over 40 years of experience with urea-based polymer technology. GPRI operates 15 manufacturing facilities throughout the United States. The company also has plants in South Americaand a manufacturing presence in South Africaand China. The company's headquarters is located at 55 Park Place, 16th Floor, Atlanta, GA30303. For additional information, please visit the company’s web sites http://www.gp.com/chemical/ and http://www.nitamin.com/ or call the Nitaminhotline at 866-2nitamin.

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Note to Editor: High resolution images are available upon request.

*The University of Georgia does not endorse Georgia-Pacific, Nitamin, or the use of Nitamin.

Nitamin is a registered trademark and Optimal Nitrogen Diet and Steady-Delivery are trademarks of Georgia-Pacific Resins, Inc.

Contacts:

Caryn E. King

Manager - Market Communications

Georgia-Pacific Resins, Inc.

Tel: 404-652-8589

ceking@gapac.com

Catherine Wang

Gibbs & Soell Public Relations

Tel: 212-697-2600

cwang@gibbs-soell.com

Media Contact:
Caryn King (404) 652-4247