376 - Maximizing Net Sucrose and Profitability
Nitrogen management is a key factor in sugarbeet profitabilityin a quality – based payment system. Numerous N management trials have been conducted in North Dakota, Minnesota, and Manitoba in the last 25 years. Early trials stressed maximizing tonnage with little regard for quality. Recent research has focused on maintaining yield, increasing recoverable sugar per ton and maximizing revenue per acre.
Q1. Are current N recommendations developed in 1988 relevant for sugarbeet production for ACSC shareholders in the new millenium?
A1. Data indicates a reduction of 10-20 lb/acre in present N recommendations will increase grower profitability.
Dr. Larry Smith, the U of Mn at Crookston has conducted twelve N rate studies in the last 4 years to answer this question and others. The research was done on heavy and light textured soils, some were planted early, some late, and some had heavy rainfall some average rainfall. Dr. Smith reported on all this research at the recent university seminars. His conclusions were that less than 120-lb/acre available soil test plus fertilizer N gave:
- Highest recoverable sugar/acre
- Highest recoverable sugar/ton
- Maximum revenue per ton
- Maximum revenue per acre
Other conclusions were that:
- There may not need to be a minimum of 80-90 lb. N in the 0-2’ soil profile for optimum yield and quality.
- Present varieties respond differently to available N than those of 10 or 20 years ago.
Table one shows the main nitrogen rate effects on sugarbeet yield and quality in 1999 research at Crookston.
Table 1. Main nitrogen rate effects averaged across varieties and harvest dates, L. Smith, U of MN, 1999.
|Available Nitrogen Rate||Yield||Net Sugar||Recoverable Sugar||Gross Return|
Conclusions from table one:
- 80 and 120 lb/acre available N gave similar sugarbeet yield and quality.
- 80 lb/acre available N gave slightly greater revenue per ton and per acre.
- Excess N (160 lb/acre) reduced yield, quality and revenue per ton and revenue per acre.
Recommendations for shareholders who did not fall apply N for the 2000 crop:
- Don’t apply more than 120 lb/acre nitrogen.
- If past N use rates have been about 120 lb/acre reduce use by 10 or 20 lb/acre on at least one field in 2000.
- Apply the reduced N rate on ½ of your most uniform field.
- Contract each half of the field separately and compare revenue per ton and per acre carefully.
The 1979 Coded Varietal Trials showed a popular variety, Hilleshog Mono 309 had a 3-year average root yield of 29.1 ton/A, sugar of 14.5%, RSA of 6866 lb and RST of 236.9 lb. Under the current 1999 ACSC payment system, that variety would be worth $17.02/ton with a gross return of $495/A. Contrast that to a high sugar variety from the 1999 Coded Variety Trials that had a root yield of only 20 ton/Acre, but a sugar content of 18%, RSA of 6601 lb, RST of 332 lb., and a gross value of $38.42/T or $765/A, with 9 fewer ton to haul and process.
Dr. Larry Smith conducted additional research in 1999 to determine profitability of sugarbeet production with different N rates and varieties differing in sugar and tonnage harvested at 4 different times. Table two shows the effect of variety averaged across all N rates and harvest dates.
Table 2. The main variety effect averaged across N rates and harvest dates. L. Smith, U of Mn, 1999.
|Variety||Yield||Net Sugar||Recoverable Sugar||Gross Return|
Q2. Have sugarbeet varieties changed in the last 20 years?
A2. Conclusions from Table 2 are that the high sugar type variety produced:
- 0.7 ton/acre less
- 0.97% higher net sucrose
- 273 lb/acre higher recoverable sugar
- 19.5 lb/ton more sugar
- $4.35/ton higher revenue
- $86/acre higher revenue
To maximize revenue from higher tonnage varieties growers should definitely consider using less N fertilizer per acre. Yield per acre will remain high and sugar content per ton will increase. All shareholders are encouraged to carefully review the 1999 research on nitrogen use for sugarbeets conducted by Dr. John Moraghan NDSU and Dr. Larry Smith, the U of Mn. It’s available in the 1999 Sugarbeet Research and Extension reports or on the Sugarbeet Research and Education Board website at SBREB.org. A link is provided on the crystalsugar.com site to SBREB.org also.