Study areas

This study was carried out in the counties of Oppland and Hedmark in south-eastern Norway (~61°N, 11°E, Fig. 1). Within these study areas, forest stands were located in Stor-Elvdal, Åmot and Rendalen municipalities in Hedmark, and Gausdal, Sør-Fron, Nord-Fron, Sel and Vågå municipalities in Oppland. The vegetation was primarily boreal forest [38] below the commercial timberline, managed for Scots pine and Norway spruce (Picea abies) timber and pulp production. Pine stands regenerate naturally, so the young pine stands in this study contained commercial and non-commercial tree species, both of which provide forage for moose. The site productivity index for pine in both areas was low to medium [39]. Stands were dominated by Scots pine, Norway spruce, and downy birch interspersed with silver birch, grey alder (Alnus incana), rowan (Sorbus aucuparia), aspen (Populus tremula), willows (Salix spp.) and juniper (Juniperus communis). The field layer vegetation was dominated by dwarf shrubs such as Vaccinium spp. The Hedmark study area was situated between 250 and 1100 m above sea level with 30-year mean summer (May–September) and winter (October–April) temperatures of 10.6 °C and −5.8 °C, respectively, in the valley bottom. The 30-year mean annual precipitation was 628 mm and the mean snow depth (October–April) was 39 cm [40]. The Oppland study area had a slightly higher elevation (515–920 m a s l), with a mean annual precipitation of 564 mm, winter temperature of −5.0 °C, summer temperature of 7.0 °C (30-year mean) and snow depth of 67 cm (average for the last 10 years). The study area was characterized by valleys and mountains and in both cases; moose tend to migrate down to the less snowy valley bottoms during winter. In the Hedmark area, winter density was approximately 1.3 moose per km² [41], for Oppland there were no records on moose density.

Map of Norway with study area indicated. Young Scots pine (Pinus sylvestris) stands were surveyed for moose browsing in the indicated areas in Hedmark (2010) and Oppland (2011)