Alfalfa Variety Trial on Heavy Soil in Graham County Arizona, 1999

Twenty four alfalfa varieties with fall dormancy ratings of 8 or 9 were tested in a replicated small plot trial on a heavy clay loam soil on the Safford Agricultural Center. This was the fourth year of the study. WL 91-224F was the highest yielding variety in 1999, but that still left it in second place behind Cuf 101 for the four year average. WL 91-224F yield was 8.35 tons per acre which is very close to its four year average of 8.32 tons per acre. CUF 101 only had the heaviest yield in one out of the past four years, but its high 1998 yield gave it the highest average yield over the four years of the study, at 8.37 tons per acre per year. Heat units with thresholds of 77o F and 41o F are included for each cutting in the study