Fall Management Effects on ‘Grasslands Matua’ Prairie Grass Production and Sward Characteristics

Abstract

Ruminant animal production costs in the northeastern USA can be lowered by extending the fall grazing season. Two field experiments were initiated with prairie grass [Bromus unioloides (Willd.) H.B.K. cv. Grasslands Matua; syn. B. willdenowii Kunth] to determine effects of fall management (i.e., clipping) on forage production and winter survival. Plantings were made in May 1986 for Exp. 1 and June 1990 for Exp. 2. Experiment 1 addressed date of fall harvest and residual stubble height effects on fall yields and tiller density, winter survival, and spring yields and tiller density. Experiment 2 addressed the interaction of harvest frequency and residual stubble height on the same parameters as for Exp. 1. Fall yields of Matua peaked at 4.0 Mg ha−1 in late October to early November (Exp. 1 and 2). Mean fall yields were reduced 20, 40, and 60% as residual stubble height was increased from 7.5 cm to 12.5, 20.0, or 25.0 cm, respectively (Exp. 1). Spring yields were high from plots clipped to a 7.5‐cm stubble in September and decreased as fall harvest was delayed to November (Exp. 1). Spring yields from plots clipped to a 7.5‐cm stubble in late November were only 20 to 25% of yields from plots clipped in September. Leaving a higher residual stubble in fall compensated considerably for the deleterious effect of harvesting in late fall. Clipping to a 20.0‐, 12.5‐ or 7.5‐cm stubble in fall resulted in linear decreases in spring yields as fall harvest was delayed from September to November, and clipping to 25.0 cm gave a quadratic response, with a peak at mid‐October. Matua plots that were harvested once in late fall or not at all (check) recovered very slowly in spring and had a lower yield potential than plots that had been harvested two, three, or four times in fall. To optimize production of Matua 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 or grazings be taken to increase stand density and winter survival.

Stockpiled Prairiegrass‐Brassica Hybrid Mixtures Tolerate Repeated Defoliation in Autumn

“…Irrespective of actual herbage mass, 95% of total yield was achieved prior to the end of October. The proportion of regrowth production relative to total stand production during autumn was similar to that obtained for swards first clipped in spring (10). Depending on when and how often stands are grazed or clipped in autumn, herbage production in the subsequent growing season could be affected, although beneficial effects appear to be species‐specific (12).…”

“…Establishing prairiegrass‐brassica hybrid stands for stockpiling provided an extended duration of herbage production in autumn, some regrowth from stands stockpiled for no more than 117 days after planting, and the potential for continuing production from the prairiegrass component of the stand. The pattern and composition of nutritive value occurring in regrowth differed from that of stockpiled herbage (3) or brassica (8,18) and prairiegrass stands (2,10), reflecting differences in local growing conditions interacting with plant development.…”

“…In central Appalachia, ‘Matua’ prairiegrass grew vigorously in autumn (2), but was damaged by winter injury and succumbed to disease the following year. Mowing or grazing Matua prairiegrass in autumn improved winter survival (10), providing a source of herbage to extend the grazing season while benefiting survival. Prairiegrass cultivars with disease resistance, upright growth habit (‘Dixon’) (13), or ability to tolerate cold weather (‘Lakota’) (14) would be suited to growing conditions in many parts of the US, but response to autumn clipping is unknown.…”

Compatibility, Yield, and Nutritive Value of Matua Prairie Grass with Interseeded Legumes

“…Matua prairie grass (Matua), Bromus willdenowi , is a short‐lived, cool‐season perennial with potential for high forage production (7). Matua can extend the grazing season, since it grows earlier in the spring and later in the fall than most other cool‐season grass species (8).…”

“…The mechanisms by which Matua persists are not well known. However, natural re‐seeding and increased tiller weights and numbers contribute to its persistence (2,7,10). Defoliation management is critical to stand longevity.…”