• Alfalfa Variety Trial in Southeastern Arizona, 1992-1993

      Clark, L. J.; Carpenter, E. W.; Cluff, R. E.; Ottman, Michael (College of Agriculture, University of Arizona (Tucson, AZ), 1994-12)
      Twenty alfalfa varieties with Fall Dormancy ratings of 8 or 9 were tested in a replicated small plot trial on the Safford Agricultural Center. The leading variety after two years of cuttings is Mesa (formerly known as 84D92, an experimental from MBS, Inc). Two other varieties with FD ratings of 6 and 10 were included in the study for comparison. Heat units with thresholds of 77° F and 40° F are included for each cutting in the study.
    • Effect of Planting Date, Nitrogen Fertility and Postemergence Herbicides on Lesquerella Production

      Nelson, J. M.; Dierig, D. A.; Hart, G. L.; Ottman, Michael (College of Agriculture, University of Arizona (Tucson, AZ), 1994-12)
      Lesquerella is a potential crop plant that produces seeds containing hydroxy fatty acids similar to those in castor beans. An important step in the commercialization of this plant for Arizona farms is the development of an efficient agronomic production system. Research on cultural practices for lesquerella was conducted during the 1991-92 and 1992-93 seasons. Results of planting date experiments indicate that early fall planting dates are superior to late fall or winter dates in terms of dry matter production and seed yield. Lesquerella produced a marked response to nitrogen (N) in tests comparing different N rates. In a postemergence weed control test, several herbicides gave good control of small winter weeds.
    • Nitrogen Fertilizer Movement in the Soil as Influenced by Nitrogen Rate and Timing in Wheat Production, 1991

      Ottman, M. J.; Vigorito, N.; Ottman, Michael (College of Agriculture, University of Arizona (Tucson, AZ), 1994-12)
    • Durum Quality is Related to Water and Nitrogen Management

      Ottman, M. J.; Doerge, T. A.; Ottman, Michael (College of Agriculture, University of Arizona (Tucson, AZ), 1994-12)
    • Small Grains Variety Evaluation at the Maricopa Agricultural Center, 1994 (Preliminary)

      Ottman, M. J.; Hareland, G.; Ottman, Michael (College of Agriculture, University of Arizona (Tucson, AZ), 1994-12)
    • Small Grains Variety Evaluation at the Maricopa Agricultural Center, 1993

      Ottman, M. J.; Hareland, G.; Ottman, Michael (College of Agriculture, University of Arizona (Tucson, AZ), 1994-12)
    • Nitrogen Fertilizer Movement in the Soil as Influenced by Nitrogen Rate and Timing in Wheat Production, 1992

      Ottman, M. J.; Vigorito, N.; Ottman, Michael (College of Agriculture, University of Arizona (Tucson, AZ), 1994-12)
      Durum wheat was grown with deficient, adequate, and excessive rates of ¹⁵N-labeled nitrogen fertilizer in order to document fertilizer nitrogen movement in the soil with differing nitrogen management. Crop water use increased with nitrogen rate due to increased vegetative growth. The amount of excess water applied increased with a decrease in nitrogen rate. Soil bromide concentrations at harvest suggest that the maximum potential depth of leaching was 3 to 6 feet. Most of the fertilizer applied in this study was recovered in the top 2 to 3 feet of soil. Fertilizer nitrogen rate and timing resulted in some differences in recovery of labeled fertilizer in the soil and plant, but did not contribute significantly to the depth of fertilizer nitrogen leaching.
    • Nitrogen Fertilizer Movement in Wheat Production, Higley

      Ottman, M. J.; Husman, S. H.; Ottman, Michael (College of Agriculture, University of Arizona (Tucson, AZ), 1994-12)
    • Alfalfa Irrigation Termination, Maricopa

      Ottman, M. J.; Roth, R. L.; Ottman, Michael (College of Agriculture, University of Arizona (Tucson, AZ), 1994-12)
      Alfalfa irrigation is often withheld as a water conservation measure in Arizona. The objective of this research was to test the hypothesis that alfalfa can be permanently damaged by withholding irrigation water. Irrigation was terminated during the summer (July or August through September) or summer through winter (July or August through mid -March) on a Casa Grande sandy loam at Maricopa. Irrigation termination at Maricopa was not detrimental to stand although hay yields were depressed from 1.47 to 1.28 tons per acre following the second cycle of summer irrigation termination and from 1.57 to 1.23 tons per acre per cutting following summer through winter irrigation termination. Alfalfa water use was reduced by irrigation termination even after irrigation was resumed. Total nonstructural carbohydrates in the roots were never less than the control during irrigation termination but decreased relative to normally irrigated alfalfa when irrigation resumed.
    • Safflower Variety by Date of Planting Trial, Safford Agricultural Center, 1993

      Clark, L. J.; Carpenter, E. W.; Ottman, Michael (College of Agriculture, University of Arizona (Tucson, AZ), 1994-12)
      Five safflower varieties were planted at five different dates on the Safford Agricultural to determine which date of planting and variety would be best for this part of the high desert of Arizona. The earliest date, February 2nd, had the highest yield across all varieties and there was no statistical difference between any of the varieties. Oil content of the seed also seemed to be highest with the earlier plantings.
    • Durum Wheat Variety Trials on the Safford Agricultural Center, 1994

      Clark, L. J.; Carpenter, E. W.; Ottman, Michael (College of Agriculture, University of Arizona (Tucson, AZ), 1994-12)
      Twenty two varieties of durum wheat were tested at the Safford Agricultural Center in 1994. One of the experimental lines, PH888-216, had the highest yield at 4152 pounds per acre. This yield was nearly 38% higher than Aldura, which has been the standard variety for many years. Durex was the highest yielding registered variety with a yield nearly 23% over that of Aldura.
    • Wheat Variety Trials on the Safford Agricultural Center, 1994

      Clark, L. J.; Carpenter, E. W.; Ottman, Michael (College of Agriculture, University of Arizona (Tucson, AZ), 1994-12)
      Thirteen varieties of wheat were tested at the Safford Agricultural Center in 1994. An experimental variety, BR6053 was the highest yielding variety in the trial with a yield of 4453 pounds per acre.
    • Barley Variety Trials at the Safford Agricultural Center, 1994

      Clark, L. J.; Carpenter, E. W.; Ottman, Michael (College of Agriculture, University of Arizona (Tucson, AZ), 1994-12)
      Ten varieties of barley were tested at the Safford Agricultural Center in 1994. Gustoe, the standard variety for the area, was the highest yielding variety in the trial.
    • National Dry Bean Nursery Trials in Bonita, 1992-1993

      Clark, L. J.; Marcarian, V.; Carpenter, E. W.; Cluff, R. E.; Call, R. E.; Ottman, Michael (College of Agriculture, University of Arizona (Tucson, AZ), 1994-12)
      Results of the 1992 and 1993 National Cooperative Dry Bean Nursery Trials are reported in this report. More than 30 varieties of seven classes of beans were tested in small plot, replicated studies. Yields, seed size, harvest index, biomass production and plant populations are among the variables recorded in the trials.
    • Alfalfa Irrigation Termination, Yuma

      Ottman, M. J.; Tickes, B. R.; Ottman, Michael (College of Agriculture, University of Arizona (Tucson, AZ), 1994-12)
      Alfalfa irrigation is often withheld as a water conservation measure in Arizona. The objective of this research was to test the hypothesis that alfalfa yield and stand can be permanently damaged by withholding irrigation water. Irrigation was terminated during the summer (July through October) or winter (November through February) on a Superstition sand in Yuma. Summer irrigation termination reduced plant density from 4 to 1.5 plants per square foot and reduced hay yield from 0.76 to 0.27 tons per acre per cutting after irrigation was resumed. Winter irrigation termination had no residual effect on yield or plant density. Termination of alfalfa irrigation can permanently damage stands and reduce yield on sandy soil.
    • Nitrogen Fertilizer Movement in Wheat Production, Yuma

      Ottman, M. J.; Husman, S. H.; Ottman, Michael (College of Agriculture, University of Arizona (Tucson, AZ), 1994-12)
    • Silage Corn Variety Trial in Greenlee County, 1993

      Clark, Lee J.; Ottman, Michael (College of Agriculture, University of Arizona (Tucson, AZ), 1994-12)
      Fourteen yellow corn hybrids were compared for silage yield at the Lunt dairy in Greenlee county. Silage yields, several agronomic variables and nutritional variables are also reported. Funks G4673B was the highest yielding hybrid in the trial with a silage yield over 20 tons per acre and net energy value nearing 10,000 megacalories per acre.
    • Nitrogen Fertilizer Movement in Wheat Production, Roll

      Ottman, M. J.; Tickes, B. R.; Ottman, Michael (College of Agriculture, University of Arizona (Tucson, AZ), 1994-12)
      Labeled nitrogen fertilizer (N-15) was applied to wheat to determine fertilizer nitrogen movement in the soil at harvest. Most of the labeled fertilizer recovered in the soil was found in the surface few feet. The amount of nitrogen fertilizer detected below S feet was minimal.
    • Yellow and White Corn Variety Trials in Cochise County, 1993

      Clark, Lee J.; Ottman, Michael (College of Agriculture, University of Arizona (Tucson, AZ), 1994-12)
      Ten yellow and twelve white corn hybrids were compared in check controlled strip trials in Cochise county. The best hybrids of both types of corn yielded just over 10, 000 pounds per acre. These yields were considered very good for the white hybrids.
    • Safflower Variety Trial in Cochise County, 1993

      Clark, Lee J.; Ottman, Michael (College of Agriculture, University of Arizona (Tucson, AZ), 1994-12)