Popis: |
Relative plant abundance, canopy cover, and aerial biomass of shrubs on a poor condition, flatwoods range in south Florida were measured before, 1, and 3 yr after a single pass of a roller chopper or web plow when soils were dry (May 1981) and when soils were saturated (September 1981). Aerial biomass of herbaceous species was measured at the post-treatment sample dates. Abundance of saw-palmetto (Serenoa repens (Bartr.) Small) plants, the dominant shrub, was reduced 70%o by web plowing compared to 25% by roller chopping. Reductions of saw-palmetto canopy cover and aerial biomass also were greater on web-plowed than on roller-chopped plots. Runner oak (Quercus minima (Sarg.) Small) was the only other shrub which had more than 5% canopy cover before treatment. Both types of mechanical treatments controlled runner oak by approximately 50%o. However, responses of runner oak abundance, canopy cover, and aerial biomass were not significantly different between roller chop and web plow treatments. |