Conservation Evidence strives to be as useful to conservationists as possible. Please take our survey to help the team improve our resource.

Providing evidence to improve practice

Individual study: Vegetation control by steam treatment in boreal forests: a comparison with burning and soil scarification

Published source details

Norberg G., Jäderlund A., Zackrisson O., Nordfjell T., Wardle D., Nilsson M. & Dolling A. (1997) Vegetation control by steam treatment in boreal forests: a comparison with burning and soil scarification. Canadian journal of forest research, 27, 2026-2033


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Prepare the ground before tree planting Forest Conservation

A replicated, randomized, controlled study in 1991-1996 in boreal forest in Sweden (Norberg et al. 1997) found that site preparation treatments increased the growth rate of planted Scots pine Pinus sylvestris seedlings. Seedling height was higher in scarification (300 mm) than control plots (250 mm), and highest in steamed plots (steamed: 350 mm; burned: 280). Stem basal area (mm2) differed among all treatments (control: 29; burned: 43; scarification: 55; steamed: 73). In August 1992, five plots (0.6 × 0.6 m) of each control (untreated), burned (ground vegetation and litter burned using a propane burner), scarification (humus layer removed from the mineral soil) and steamed (amount of steam equivalent to 13 L of water evenly sprayed over each plot for 2 minutes) treatments were replicated in 40 blocks that were clearcut in 1991–1992. In June 1993, one scots pine seedling was planted in each plot. Data were collected in 1996.