Author
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JUNG G A - 1902-05-00 |
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SHAFFER J A - 1902-05-00 |
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EVERHART J R - 1902-05-00 |
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Submitted to: Crop Science
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 10/8/1993 Publication Date: N/A Citation: N/A Interpretive Summary: Research investigations were initiated in Pennsylvania to evaluate the potential of a new grass, Grasslands Matua prairie grass, from New Zealand to extend the fall grazing season. It is well established that extending the grazing season lowers dairy and animal production costs. Matua prairie grass has a bunch type growth habit, and it produces palatable flowerheads in every crop. Early trials with Matua in New Zealand showed that this grass was sensitive to grazing management. However, little information was collected on response to fall management. Our studies concentrated on the effects of time and frequency of herbage removal in fall, as well as the severity of herbage removal on Matua's herbage production and winter survival. When Matua was allowed to accumulate herbage from late August to December, herbage yields peaked at 4.0 t ha-1 in late October/early November in two of three years. Single clippings in late fall or none at all often resulted in poor winter survival, slow recovery in spring, and low spring yields. Clipping above 7.5 cm markedly reduced fall herbage yield, but single clipping above 7.5 cm in mid-fall improved spring yield. To optimize production of Matua prairie grass in fall and spring, it is recommended that one summer rest period be extended to allow natural reseeding and that two or three fall harvests/grazings be taken to increase stand density and winter survival. Technical Abstract: Dairy and animal production costs can be lowered by extending the fall grazing season. Investigations were initiated in 1986 to evaluate the potential of Matua prairie grass to extend the grazing season and to survive Pennsylvania winters. Plantings were made on Hagerstown silt loam (fine, mixed, mesic Typic Hapludalf) in May 1986 for Experiment 1 and June 1990 for Experiment 2. Experiment 1 concerned time of fall harvest and harvest severity effects on fall yields, tiller density, winter survival and spring yield. Experiment 2 concerned the interaction of harvest frequency and severity on the same parameters as for Experiment 1. The experimental design used in Experiment 1 was a strip plot design with harvest date as whole plots and stubble height as subplots, with four replicates. A randomized complete block design was used in Experiment 2, with a factorial treatment structure and five replicates. Fall yields of Matua prairie grass peaked each year in late October/early November, with 4.0 t ha-1 yields in two of three years (Exp. 1). Two years mean fall yields were reduced 20%, 40% and 60% as clipping height was increased from 7.5 cm to 12.5 cm, 20.0 cm or 25.0 cm, respectively. Spring yields were high from plots clipped in September and decreased as fall harvest was delayed. Spring yield from plots harvested in December were only 20 to 25% of yields from plots harvested in September. When Matua was cut to a 25.0 cm stubble in fall, time of fall harvest was of no consequence. But clipping to a 20.0 and 12.5 cm stubble resulted in linear decreases in spring yields as fall harvest was delayed from September to November, and clipping to 7.5 cm gave a quadratic response, with a minimum at mid- November. Matua plots that were harvested once in late fall or not at all |
