The review examined primary field studies of the effects of prescribed burning on biodiversity in boreal and temperate forests in protected areas or under commercial management.
Searches generated a total of 12,971 unique records. After screening for relevance, 244 studies (from 235 articles) were included in this review. Most studied forests were located in the USA (172/244), with the rest located in Canada, Europe and Australia.
Eighty-two studies reporting 219 comparisons were included in the quantitative synthesis. Within the meta-analyses for each group of taxa, we identified a small to moderate volume of evidence, and heterogeneity was ubiquitous. Prescribed burning had significant positive effects on vascular plant richness, non-native vascular plant richness and, in broadleaf forests, herbaceous plant richness. Time since the burn, forest type and climate zone were significant moderators predicting the effect of burning on herbaceous plant richness. No other significant relationships were identified.
Rather than making any general recommendations on the use of prescribed burning for biodiversity restoration, the authors provide an evidence atlas of previous studies for researchers and practitioners to use.
They also observe that outcomes are still difficult to predict, and any restoration project should include a component of monitoring to build a stronger evidence base for recommendations and guidelines on how to best achieve conservation targets.
Prescribed burning may have harmful effects on taxa that are conservation-dependent and careful planning is needed.