AN ECONOMIC-ANALYSIS OF ALTERNATIVE NITROGEN-FERTILIZATION METHODS FOR SUGAR-BEETS

Sugarbeet (Beta vulgaris L.) producers face unique challenges in N fer tilizer management because of the relationships among price, sucrose c ontent, and root yield. This study evaluates the economic efficiency o f N fertilizer applications using broadcast, knife band, and point inj ection application methods. The most profitable rate of N was examined for each application method under goals of profit maximization, root yield maximization, sucrose-yield maximization, and recoverable sucros e-yield maximization, This study was based on production data collecte d at the University of Wyoming Research and Extension Center at Powell from 1991 to 1993. The experiment was conducted as a randomized compl ete-block design with four replications of each treatment. Treatments consisted of a control (no applied N) and factorial combinations of fo ur N rates (80, 160, 240, and 320 1b N/acre in 1991 and 60, 120, 180, and 240 lb N/acre in 1992 and 1993) with each application method, Resp onse functions relating the amount of N applied to gross returns, root yield, sucrose yield, and recoverable sucrose yield for each of the t hree application methods were used to derive the optimal amount of N t o be applied. Point injection returned $966/acre above fertilizer and beet hauling costs while broadcasting and knife banding returned $899/ acre and $872/acre, respectively. Profit maximizing N rates were 187 l b/acre for point injection, 187 lb/acre for knife branding, aod 220 lb /acre for broadcasting. The goal of maximizing profits returned the gr eatest income above fertilizer and beet hauling costs. Maximizing root yield returned the least income above fertilizer and beef hauling cos ts and required the most N, Maximizing sucrase or recoverable sucrose yield returned income above fertilizer and best hauling cosh and used fertilizer levels that fell between those of maximizing profit and roo t yield.