Recent Research Indicates Plant Community Responses to Intensive Treatment Including Chemical Amendments
Abstract Plant community responses to several factors (planted species, competition control, and nutrients) that influence stand development were tested in a factorial experiment on a flatwoods Spodosol. A moisture gradient across replications, augmented by irrigation, permitted testing of afourth factor (moisture regime). There were differences between slash pine (Pinus elliottii var. elliottii Engelm.) and loblolly pine (Pinus taeda L.) crown development, but no response to moisture gradient. Pines and other plants responded dramatically to continuing competition control andrepeated fertilization. Nonpine crown cover was reduced from 100% on plots without herbicides to less than 10% on treated plots. Pine crown cover at 5 years averaged 73% with both fertilization and competition control versus 11% on control plots. Both pine and nonpine cover changed significantlyacross bed, furrow, and interbed niches, and niche interacted with chemical (fertilizer and herbicide) treatment. Competition control dramatically reduced plant species richness; modal number of species observed on 5 m transects was reduced from 10 on plots without herbicides to 2 on plotsrepeatedly treated. South. J. Appl. For. 13(3):152-156.