• Alfalfa Variety Trial in Cochise County, Arizona, 1997

      Clark, L. J.; Carpenter, E. W.; Ottman, Michael J. (College of Agriculture, University of Arizona (Tucson, AZ), 1998-10)
      Fourteen alfalfa varieties with fall dormancy ratings from 6 to 9 were tested in replicated small plot trials on the Kibler farm in Stewart District northwest of Willcox. The leading variety after three years of testing was DeKalb 189 with a dry matter yield of 8 tons per acre. Heat units with temperature thresholds of 77 °F and 40 °F are given for each cutting.
    • First Year Field Evaluation of Nine Alfalfa Varieties Planted October 1997 on the Colorado River Indian Tribes Reservation

      Rethwisch, Michael D.; Kruse, Michael; Torres, Javier; Torres, Miguel; Ottman, Michael J. (College of Agriculture, University of Arizona (Tucson, AZ), 1998-10)
      Nine alfalfa varieties, most not previously tested under field conditions in Arizona, were planted October 29, 1997 using the same setting on a Great Plains Solid Stand 13 End Wheel drill. Varieties differed in lbs. of seed/acre planted, ranging from 28.0 for CUF 101 to 21.3 for Alto. Five cuttings were obtained through August 1998. The variety Alto yielded the most hay in the first and fourth cuttings and had the highest total yield from the first five harvests. Varieties with fall dormancy class ratings of 8 usually had higher yields than varieties of dormancy 9 during the spring and early summer growing season, which was below normal in temperature, resulting in class 8 dormancies having the highest total yields thus far.
    • Alfalfa Variety Trial in Graham County Arizona, 1997

      Clark, L. J.; Carpenter, E. W.; Ottman, Michael J. (College of Agriculture, University of Arizona (Tucson, AZ), 1998-10)
      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 second year of a new study. UC 331 had the highest yield for the year but CUF 101 had the highest average yield. Heat units with thresholds of 77° F and 40° F are included for each cutting in the study.
    • Three Year Summary of Yield, Weed Infestation and Other Attributes of Five Alfalfa Varieties Planted October 1994 on the Colorado River Indian Tribes Reservation

      Rethwisch, Michael D.; Baldwin, Bill; Baldwin, Joan; Leivas, Danny; Kruse, Michael; Ottman, Michael J. (College of Agriculture, University of Arizona (Tucson, AZ), 1998-10)
      Five alfalfa varieties (CUF 101, SW 14, SW8210, Pioneer 5888, and a grower selection originating from CUF 101 and noted as Baldwin Select) that were planted in October, 1994, into large plots (0.75 acres) to obtain actual field harvest data production during the years of 1995-1997. Varietal hay yields were very similar in 1995 until mid summer, when area soil temperatures reached above 100°F at the four inch depth for a period of about 6 weeks. During the summer months Baldwin Select had significantly higher yields than other varieties tested. Statistical differences in accumulated hay yields were noted beginning in August 1995 and continued through 1997. Baldwin Select was the highest yielding variety each year, producing 8.4% more than CUF 101 during this time period, worth $247/acre more an acre than CUf 101. Alfalfa varieties were similar in relative feed value. Yellowing from Empoasca spp. leafhoppers was greatest during the 1995-1996 winter on varieties with fall dormancy ratings of 9 or greater. Weed infestations during late summer 1996 appear inversely correlated with fall dormancy class. All varieties of dormancy classes 8 and 9 were almost 100% infested with weeds during September 1997, although Baldwin Select had significantly less infestation. Differences in plant populations in late September 1997 also appear to be correlated with fall dormancy class.