Terravent TM: Soil fracture patterns and impact on bulk density

Abstract

Soil compaction is reported to be a limiting factor in many urban tree plantings. The TerraventTM was developed to decompact and aerate soil through the soil injection of high-pressure nitrogen gas. The purpose of this project was to determine the soil fracture patterns created by the Terravent and to determine if soil bulk density is reduced. Replicates of six fractures were made at three sites. Bulk density and the degree of fracturing were measured. No significant differences in soil bulk density were found between treated and nontreated areas. Fracture patterns were generally horizontal to convex shaped with a mean width up to 22.2 in. (56 cm), typically 9 in. (23 cm) below the soil surface. Other means of alleviating soil compaction are thought to be more effective.