Immediate tree uprooting after retention-felling in a coniferous boreal forest in Fennoscandia

Abstract

We studied the immediate effects of retention-felling on the occurrence of tree uprooting in two different types of boreal spruce forest in Finland to determine whether susceptibility to uprooting is dependent on the biotope. During the first post-treatment year, 7.1% of the trees in the paludified forest type and 1.8% in the upland forest type were uprooted. During the 2 following post-treatment years, uprooting percentages increased considerably (39.3% in the paludified type and 11.5% in the upland type in year 2; 48.3% in the paludified type and 15.2% in the upland type in year 3). Norway spruce (Picea abies (L.) Karst.), the dominant species in both forest types, was the species most susceptible to uprooting. The high uprooting rate in the paludified groups was probably caused by an interaction between the rocky ground and moist overlying peat layer with the shallow root system of P. abies. As paludified forest biotopes are generally recognized to have high biodiversity, the use of green-tree retention in these biotypes may enhance the continuum and survival of sensitive species. Moreover, because of the high level of uprooting, green-tree retention in paludified forest types can quickly and more naturally help restore levels of coarse woody debris.

Windthrow after group and dispersed tree retention in eastern Canada

“…This is consistent with all other studies of windthrow following variable retention harvesting (Bebber et al, 2005;Hautala and Vanha-Majamaa, 2006;Steventon, 2011). It thus seems clear that retention cuts increase the risk of windthrow compared to stands situated within an intact forest matrix.…”

“…Green tree retention can lead to higher levels of windthrow compared to untouched forests (Bebber et al, 2005;Bladon et al, 2008;Busby et al, 2006;Hautala and Vanha-Majamaa, 2006;Scott and Mitchell, 2005). While gradual tree mortality can provide a desired input of dead wood over the medium term, high levels of mortality in the years immediately following cutting may impact species that depend on standing live trees and compromise the longer term recruitment of dead wood (Thorpe and Thomas, 2007).…”

“…Hautala and Vanha-Majamaa (2006) reported windthrow losses varying between 15% and 48% of the number of stems for Norway spruce (Picea abies (L.) Karst.) after three years, depending on soil type.…”

Tree retention as a conservation measure in clear-cut forests of northern Europe: a review of ecological consequences

“…The smaller the patches (the range was 1/16 to 1 ha), the higher the recorded mortality. Hautala et al (2006) monitored tree dynamics on spruce-dominated patches in southern Finland. In their study area, the size of the retention patches affected tree uprooting only slightly.…”

Cost-effective strategies to conserve boreal forest biodiversity and long-term landscape-level maintenance of habitats

“…Our models on the dead-wood dynamics in the GTR patches may miss some important aspects. For example, it has recently been shown that the amount of CWD may be higher in GTR patches than in comparable mature forests, probably because windstorms increase dead-wood formation in edge-prone GTR patches (Hautala and Vanha-Majamaa 2006;Jönsson et al 2007). Thus, GTR may promote the distribution of key forest attributes in a landscape.…”