EFFECTS ON TREES OF AN ILLUMINATING GAS IN THE SOIL

Abstract

Problems concerned with trees injured by illuminating gas accidentally leaking into the soil may be said to have commenced in 1807 when the first public street gas lighting system was installed in Pall Mall, London (10). Although various phases of the problems presented when illuminating gas is seeping into soil in which the roots of plants are growing have been investigated by botanists, chemists, and others for at least seventy years, no general agreement has been reached upon the exact manner in which vegetation is injured, killed, or otherwise influenced. A brief survey of the literature consulted is given to establish the present status of the general problem. Neuman in 1842, according to Girardin (12), described the poisoning of elm trees by gas. By 1864, Girardin, in Lille, France, was studying the soil for the cause of severe injury to Italian poplar trees located near a leaking gas conduit. About this time injuries to street trees were being reported from a number of European cities. The cause of the injury, and death of shade trees on several of the chief thoroughfares in Berlin brought about an extended controversy. This was described by Laissus and Heim (16). Some thought that gas in the soil was responsible; others thought that unfavorable conditions of water supply, nutrition, high temperatures, and other factors were chiefly responsible for the conditions of these trees. It was suggested that the soil around the roots of the trees should be inclosed by impervious cylindrical walls to avoid the action of illuminating gas, from leaking conduits, on the trees. In 1900, Wehmer (25) described the injury of elm trees in the vicinity of a gas leak in Hanover, Germany, and included an illustration showing the leafless condition of the tops of the trees and the sloughing off of large patches of the basal bark. In 1903 (18), at Yonkers, New York, considerable trouble was experienced owing to gas injuries upon shade trees. The writings of Stone (21, 22, 23, 24), from 1906 to 1916, gave evidence of the frequent instances of injuries to trees in New England which were attributed to the escape of illuminating gas in the soil. In recent years, in the United States field cases of gas in the soil affecting tree growth unfavorably have rarely been reported in the scientific literature. Accidental occurrences of this type are more frequent than is generally supposed. When they involve a conspicuous shade tree or extensive injury to a number of trees in a small locality the necessity for information upon the factors involved, accurate diagnosis, and possible remedial measures become urgent.