THE LONG TERM EFFECT OF UTILITY TRENCHING ON GROWTH AND OVERALL PLANT HEALTH OF SELECTED SPECIES OF SHADE TREES

Abstract

Summary New telephone lines were installed in trenches throughout the campus of the University of Illinois at Urbana-Champaign in the spring of 1987. The trenches were in close proximity to tree trunks. Annual growth and mortality data were taken on Celtis occidentalis, Liquidambar styraciflua, Acer saccharum, and Gleditsia triacanthos through 1991. Only 7 of 98 trees died during the trial period. Trenching distances of 0.5 to 3.3 m. did not predispose the trees to readily evident disease or insect infestations. Only on Celtis occidentalis was there statistically different growth between trenched and control trees for all growing seasons.