Root Competition: Towards a Mechanistic Understanding

Current evidence suggests that competition belowground is a ubiquitous phenomenon in many natural and semi-natural types of vegetation. In reviewing 23 studies that separated root and shoot competition under controlled conditions, Wilson (1988) found that root competition was usually the more intense form of interaction. Even in relatively productive soils where plants produce large canopies and competition for light may be expected to be an important factor, root interactions may still play a significant role. Several studies (Belcher et al. 1995; Gerry and Wilson 1995; Cahill 1999) have confirmed the significance of belowground interactions in competition under field conditions.