Understory vascular plant responses to retention harvesting with and without prescribed fire

Abstract

Wildfire is the predominant natural disturbance in the boreal forests of western Canada. Natural disturbance based forest management involves the use of retention harvesting to retain stand structural diversity after harvest; however, unlike fire, this partial harvesting technique does not cause combustion of the forest floor. Application of prescribed burning to areas treated with retention harvesting might emulate the influence of wildfires more effectively than harvesting alone. We compared understory vascular plant diversity, abundance, and composition between forest stands subjected to dispersed retention harvesting (10% retention) with and without prescribed burning 1, 6, and 11 or 12 years after burning. Untreated forest was included as a reference. Research was conducted in conifer-dominated, mixedwood, and deciduous-dominated boreal forest stands in northwestern Alberta, Canada. In deciduous-dominated stands, burned areas of retention harvested stands had higher species richness and greater cover than did unburned areas. In all three forest cover types, effects of harvest with and without burn on species richness, cover, and composition were still evident a decade after disturbance. Fire-adapted species benefited most from the prescribed burn treatment. The combination of prescribed burning with retention harvesting can be considered a useful option in forest management that aims to emulate natural disturbance.

Fire Regime Has a Greater Impact Than Selective Timber Harvesting on Vegetation in a Sub-Tropical Australian Eucalypt Forest

“…Combined effects of fire and selective cutting on vegetation were also minor in Sudanese savanna woodlands [55] and for eucalypt forests in southern Australia [15]. However, stronger interactive effects of fire and timber harvesting have been reported elsewhere e.g., [14,56,57]. Barefoot et al [56] reported that overstorey thinning coupled with prescribed fire resulted in increases in ground flora richness, diversity and cover in mixed Pinus-hardwood stands in Alabama, USA.…”

Disentangling the direct and indirect effects of canopy and understory vegetation on the foraging habitat selection of the brown bear Ursus arctos

“…Given the dominant understory species generally differ among ecoregions where brown bears inhabit (e.g. Hokkaido, Japan: dwarf bamboo (Hiura et al 1996), Alberta in Canada and Sweden: berries (Nilsson and Wardle 2005, Franklin et al 2019), Carpathian Mountain, Poland: ferns and berries (Ciarkowska and Miechówka 2019)), evaluation of the role of the understory in brown bear ecology and management should carefully consider regional differences. Additionally, understanding spatial patterns of habitat selection can assist prediction of bear–human conflict (Northrup et al 2012).…”

Detection of standing retention trees in boreal forests with airborne laser scanning point clouds and multispectral imagery

“…Besides tree‐level attributes, the positioning of retention trees plays a crucial role in the effectiveness of retention trees, both within a stand (e.g. grouped vs. single tree retention and vicinity to intact stands, Franklin et al, 2019; Gibbons et al, 2008) and in the wider landscape (Mori et al, 2017; Vandekerkhove et al, 2013).…”