Apply herbicides after restoration planting
Overall effectiveness category Unknown effectiveness (limited evidence)
Number of studies: 1
Background information and definitions
Harvesting and replanting have substantial effects on forest biodiversity conservation and maintenance of long-term productivity. Herbicides have been extensively evaluated for their potential to release planted trees from competing vegetation.
Supporting evidence from individual studies
A replicated, randomized, controlled study in 1999-2006 in temperate coniferous forest in Washington State, USA (1) found that controlling vegetation using herbicides after restoration planting decreased plant species richness and diversity. Species richness (control: 24; herbicide: 17) and diversity (Simpson's index control: 0.83; herbicide: 0.35) were lower in treated plots. Data were collected in 2006 in two plots (30 × 85 m) of each control and herbicide (annual herbicide applications) treatments in each of four blocks that had been clearcut in 1999. In all plots tree trunks were removed and Douglas-fir Pseudotsuga menziesii seedlings were planted in 2000.Study and other actions tested