• Effects of Sewage Sludge on Yield and Quality of Wheat Grain and Straw in an Arid Environment

      Day, A. D.; Thompson, R. K.; Swingle, R. S.; Department of Plant Sciences, University of Arizona; Department of Animal Sciences, University of Arizona (University of Arizona (Tucson, AZ), 1987)
      A 6-year experiment (1978) through 1983) was conducted at the Mesa Agricultural Center, Mesa Arizona, U.S.A. to study the effectiveness of dried sewage sludge as a fertilizer source for the production of grain and straw from 'Zaragoza' wheat (Triticum aestivum L.). Three fertilizer treatments were applied each year before planting on a laveen loam soil, a member of the coarse-loamy, mixed, hyperthermic Typic Calciorthids. The treatments consisted of: (1) suggested rates of nitrogen (N), phosphorus (P), and potassium (K) in Arizona-160, 81, and 0 kg ha⁻¹ of N, P₂O₅, and K₂O; respectively; (2) 10 Mg ha⁻¹ of dried sewage sludge to supply N in amounts equal to the suggested rate; and (3) inorganic fertilizer to provide N, P, and K in amounts equal to those applied in the sewage sludge-160, 310, and 36 Kg ha⁻¹ of N, P₂O₅ and K₂O; respectively. Average number of days from planting to harvest, plant height, grain yield, grain volume-weight, and grain/straw ratio were similar for wheat grown with all fertilizer treatments. In vitro dry matter disappearance (IVDMD) and total protein concentration in wheat grain were similar for all fertilizer treatments. In vitro dry matter disappearance and total protein concentrations in wheat straw grown with sewage sludge alone were higher than they were in straw from wheat grown with suggested N, P, and K from commercial fertilizer. Wheat grain and straw from all fertilizer treatments contained relatively low concentrations of cadmium, zinc, copper, lead and nickel. Concentrations of N, P, K, Na and total soluble salts were higher in soil fertilized with dried sewage sludge for 6 years than they were in the original soil.
    • Effects of Soil Materials, Mulching Treatments, and Soil Moisture on the Growth and Yield of Western Wheatgrass for Coal Mine Reclamation

      Day, A. D.; Ludeke, K. L.; Department of Plant Sciences, University of Arizona; Ludeke Corporation (University of Arizona (Tucson, AZ), 1987)
      A 3-year experiment was conducted in the greenhouse at Tucson, Arizona to study the effects of three soil materials, three mulching treatments, and two soil moisture treatments on the growth and forage production of western wheatgrass (Agropyron smithii Rydb.) when used in the reclamation of coal mine spoil. The three mulching treatments were: (1) No mulch. (2) Barley (Hordeum vulgare L.) straw mulch, and (3) Russian thistle (Salsola kali L.) mulch. The two soil moisture treatments consisted of: (1) Optimum (60 cm total) and (2) Stressed (30 cm total). There were significant differences in number of stems per pot, plant height, and forage yield between soil materials, mulching treatments, and soil moisture treatments. The Gila loam soil, barley straw mulch, and optimum soil moisture treatment produced the highest number of stems per plot, the tallest plants, and the highest yield of forage. Plants were more vigorous and produced more forage when soil mulch (incorporated organic matter mulch) was used than when soils were not mulched. Barley straw and Russian thistle were of similar value as mulching materials. Within soil materials and within mulching treatments forage yields were significantly higher with optimum soil moisture than they were when moisture was limited.