Leguminous Plants Increase Sycamore Growth in Northern Alabama

Abstract

Abstract Tree growth in a 2‐year‐old sycamore ( Platanus occidentalis L.) plantation in northern Alabama significantly increased over the following 4 years after three clovers and two vetches were grown with the trees. Leguminous plants were chosen to: (i) provide weed control through good ground coverage, (ii) maintain a low profile, (iii) grow during the cool season so as not to compete with the sycamore, (iv) provide cover for several years after establishment through their ability to reseed, and (v) make additional nitrogen (N) available through the fixation process. Following establishment of the leguminous plants, sycamore height and volume growth were increased as were N concentrations in sycamore foliage. Of the plants tested, Mississippi subterranean ( Trifolium subteraneum L.) and crimson clovers ( T. incarnatum L.) gave good ground coverage, maintained a low profile, reseeded themselves well, and increased the N content of sycamore foliage in addition to improving height and volume growth.