• Scheduling Pima Cotton Irrigations Using Infrared Thermometers

      Garrot, D. J. Jr.; Fangmeier, D. D.; Husman, S. H.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
      Plots of pima S-6 cotton were scheduled for irrigation using the Crop Water Stress Index (CWSI). Irrigations were applied when CWSI levels reached 0.08 (wet), 0.34 (medium), and 0.68 (dry) units. The medium treatment had significantly higher lint yield. Preliminary test results indicate the CWSI can be useful in irrigation-management decisions regarding pima cotton production.
    • Short and Long Staple Variety Trials, Greenlee County, 1988

      DeRosa, E.; Clark, L. J.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
      Two short staple variety trials and 1 long staple variety trial were harvested in Greenlee county in 1988. In the short staple trial comparing the new and experimental New Mexico acalas with 2 other lower quality varieties, Genhains new GC 260 was the top yielding variety with 1,087 pounds of lint per acre, but it came in fifth when comparing dollar value per acre because of the premium structure for the New Mexico acalas. Two new experimental acalas, 2745 and B510, produced the highest income per acre. The short staple trial, which tested longer - season varieties, had problems with low micronaire values. The newly released 1517-88 variety produced the top yield and produced the most income per acre. Two of the experimental long staple varieties topped the yield of S-6 and 3 of the 7 varieties tested yielded over 650 pounds of lint per acre.
    • Short Staple Variety Demonstration, Graham County, 1988

      Clark, L. J.; Cluff, R. E.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
      Cotton lint yields in the variety trials in Graham county were higher than the 1987 yields by close to 200 pounds per acre. Two varieties, BR 110 and NK KNX 111 (now KC 311) yielded more than DP 90 at the Thatcher site, the highest yield being 1,569 pounds of lint per acre. In Eden, DP 90 was the highest yielding variety with 1,237 pounds of lint per acre. The New Mexico acalas didn't yield as much lint per acre as the top yielding varieties, but with 1988's premium, produced substantial income per acre. In Thatcher the highest yielding acala produced $861 per acre compared with BR 110's $910, whereas in Eden the highest yielding acala produced $736 per acre against DP 90's $717.
    • Short Staple Variety Demonstrations, Pinal County

      Malcuit, J.; Stedman, S.; Silvertooth, J.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
    • Short Staple Variety Trial, Cochise County, 1988

      Clark, L. J.; Schwennesen, E.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
      Nine acala varieties were grown in the Cochise area of Cochise county. An experimental New Mexico variety B510 was the top yielder in the test, producing 1,287 pounds of lint per acre. The top variety in 1987, 1517-77BR, was next to the bottom in the 1988 test, probably due to low plant population. Variety characteristics such as plant height, wilt susceptibility, relative maturity and lint turnout are quantified in the study along with final plant populations and lint quality. Information on cotton variety strip trials implemented in the county is also given.
    • Soil Amendments on Cotton, Safford Agricultural Center, 1988

      Clark, L. J.; Carpenter, E. W.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
      Cotton was grown in the fourth year of a soil amendment trial that evaluated 4 different soil amendments in 12 treatments on the Safford Agricultural Center. Yields varied from 1,659 to 1,392 pounds of lint per acre but none of the treatments yielded statistically different from the check. The higher yields were seen in the treatments with high and medium rates of soil sulfur, Boligrow, or gypsum, the lower yields were seen in the treatments with low rates of those amendments or with a biological amendment, but the conclusion of the study is that soil amendments did not significantly increase yields on that soil with its EC value of 2.3 dS/m. Crop and fiber quality measurements are reported here.
    • Strategies to Capture Higher Gross Revenues

      Firch, R. S.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
      Research on futures price behavior indicates that farmers may find it feasible to use selective hedging or forward contracting to increase gross receipts from the sale of their commodities. University economists have been telling farmers for many years that selective hedging-hedging only in some years rather than all years or no years -- should not be considered as an alternative to hedging every year or never hedging. If selective hedging is to be a feasible strategy for farmers, they must have some system for correctly predicting the direction of futures price changes during the production period in most years.
    • Successes and Failures in Foliar Applications to Correct Zinc Deficiency

      Mauney, J. R.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
    • Tierra Prospera Farms CWSI Irrigation Scheduling Demonstration Test

      Garrot, D. J. Jr.; Stedman, S.; Benedict, D. B.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
    • Variety and Date-of-Planting Test

      Pegelow, E. J. Jr.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
      Three upland cotton varielies--Stoneville 506, Deltapine 20, and Deltapine 77--were planted on 4 dates in 1988 at the Maricopa Agricultural Center and observed for flowering boll opening and lint yield. Results from the 1988 studies and those from similar tests in 1985-1987 are being used to determine the relationship of accumulated heat units to the timing of key stages in crop development.
    • Yield, Earliness, and Response to Pink Bollworm of a Resistant Line and a Standard Cultivar Treated with Ethephon and Untreated

      Wilson, F. D.; Flint, H. M.; Bariola, L. A.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)
      An experimental cotton line, WC-12NL (nectariless, okra leaf early maturing) was compared in large plot (2-acre) replicated experiments with a standard cultivar, 'Deltapine 61' ( nectaried, regular leaf shape, full-season), for 3 seasons, 1986 to 1984 at 2 locations, Maricopa, AZ and Brawley, CA. Ethephon ("Prep") was applied to half of each plot when the crop was ca. 60% open. Pink bollworm (PBW) eggs were counted twice weekly on bolls and the 2 cottons were sprayed separately for PBW control when the egg infestation on bolls reached the action level. Seed cotton was harvested weekly as soon as bolls started to open. Over the 3 seasons and 2 locations, WC 12NL yielded 12% more total lint, 43% more cumulative lint at the third harvest date, and required only 59% as much insecticide to control PBW as did Deltapine 61.