Summer Regrowth of Tall Fescue: Stubble Characteristics and Microenvironment
1981
Stringer, W. C. | Wolf, D. D. | Blaser, R. E.
Stand thinning has been observed when N-fertilized cool-season grasses are harvested in late spring. These losses appear to be greater when hot, clear weather follows a harvest. Earlier spring cuts appear to ameliorate the stress. This 2-year investigation examined effects of spring N at 50 and 160 kg/ha; and spring cutting (biweekly, monthly, and zero spring cuts) to 5 and 10 cm stubbles on regrowth of tall fescue (Festuca arundinacea Schreb.). Stubble canopy structure, microenvironment, and stand regrowth were examined following a June harvest at which all plots were moved at their respective cutting heights (save an unharvested check). The high N rate caused greater forage yields to be present at the June harvest. Stubble leaf area index (LAI), vegetative tiller density, and live stubble yields were not affected by N rate. Cutting during spring increased tiller density and LAI. Cutting managements had significant effects on the stubble temperafure and soil temperature that were associated negatively with stubble LA1 and tiller density. There was no detrimental effect of cutting management or N rate on stand recovery except in 1975 when lodged areas of spring accumulated swards with high N fertilization had poor regrowth. Stand losses in these area was associated with only 3 to 4% noncarbohydrates (TNC) in the stubble. Lodging is hypothesized to be partially responsible for stand losses in dense stands through detrimental effects on TNC storage and other unknown effects.
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