Effect of fertilizer on seed yield of alfalfa under irrigation in Saskatchewan

Abstract

The impact of fertilizers containing macro- and micro-nutrients on seed production of alfalfa under irrigation in Saskatchewan was assessed. Trials were conducted on a Sutherland clay loam at Saskatoon, SK, from 1986 to 1991, and in a commercial field on Asquith sandy loam near Outlook, SK, from 1990 to 1993. Nutrients (primarily combinations of P, K, S) were applied at establishment (in-row with seed, side-banded, or broadcast and incorporated prior to seeding), and/or broadcast on the soil surface each year. Seed yield at both sites was excellent for the region, and application of fertilizer had little or no impact on yield. At sites with adequate initial soil fertility, as indicated by soil testing, alfalfa may not require added fertilizer to maintain high levels of seed production.