FERTILIZER AND LIME INFLUENCE ON ENGMO TIMOTHY YIELD AND MINERAL COMPOSITION ON THE LOWER KENAI PENINSULA OF ALASKA

• Main Authors: Laughlin, Winston M., Smith, Glenn R., Peters, Mary Ann, Martin, Paul F.
• Format: Report
• Language: unknown
• Published: Agricultural Experiment Station, School of Agriculture and Land Resources Management, University of Alaska 1981
• Subjects: Caribou Hills; Engmo; Kachemak; Alaska
• Online Access: http://hdl.handle.net/11122/2438

This report contains the results of a cooperative investigation between Agricultural Reseach, Science and Education Administration, United States Department of Agriculture, and the Palmer Research Center, Agricultural Experiment Station, University of Alaska. Another forage to supplement the native bluejoint (Calamagrostis canadensis) in the Caribou Hills area on Alaska’s lower Kenai Peninsula is needed. Domestic grass growth has seldom been successful, although timothy (Phleum pratense) is more tolerant of the acid conditions found in this area than are many other grasses suited for use in Alaska. This report summarizes the results of three separate experiments evaluating the effects of lime and fertilizers on forage production and chemical composition of Engmo timothy on Kachemak silt loam (Typic Cryandept). A 3-year study showed that lime markedly improved growth and yield of tim othy in an area where domestic grasses had seldom survived. Ammonium phosphate nitrate, calcium metaphosphate, and treblesuperphosphate were equally effective as a source of phosphorus (P). In an adjacent 6-year study, each lime increment over 1 ton per acre increased the soil pH, forage yield, and nitrogen (N) uptake, and tended to reduce the crude-protein concentration in forage. Increasing N applications increased yields, crude-protein percentage, and N uptake. Native bluejoint gradually replaced the timothy on plots receiving less than 2 tons lime per acre, responded to the high N rate, and thrived with two cuttings per growing season. In a 5 -year study, oven-dry yields of both cuttings increased with N rates up to 120 lb N per acre with no further increase at 180 lb N per acre. Each increasing N rate each year increased the crude protein and nitrate (N 0 3 -N) concentrations of both cuttings. Nitrogen rates exceeding 60 lb N per acre increased the mean seasonal P uptake and tended to increase the P concentration. Mean seasonal potassium (K) uptake varied with N rate as follows: 120>180 and 240> 60 lb N per acre. Each ...