Productivity of Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) in coastal areas of northern Sweden
Productivity of Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) was
studied on 12 sites in coastal areas of northern Sweden. On each site, sample
plots were placed in adjacent Norway spruce and Scots pine stands with similar
ages in between. Basal area, tree height, Site Index, volume production,
simulated maximum mean annual increment (MAImax) and tree vitality were
compared for the two species. Average basal area at the time of measurement
was 30.4% larger for Scots pine stands than for Norway spruce stands. The
difference between the two species in basal area increment during the last 10
years was related to stand age. Basal area increment of Scots pine was larger
than Norway spruce for young stands, and smaller than Norway spruce for older
ones. Average height was 2.3 m higher for Scots pine stands than for Norway
spruce stands. Height growth in the last year was also higher for Scots pine. Site
Index (SI) for the two species was similar on most sites except for three sites,
where SI for Scots pine was more than 10% larger than for Norway spruce. Total
volume production for Scots pine stands was 29.9% higher than for Norway
spruce stands. On average, simulated MAImax was 13.8% higher for Scots pine
than for Norway spruce, and age for reaching MAImax was 16 years later for
Norway spruce than Scots pine. Tree vitality was higher for Norway spruce than
for Scots pine largely due to browsing by moose. Total damage rates were 16.0%
and 4.6% for Scots pine and Norway spruce, respectively. The results from this
study indicate that Scots pine has higher productivity than Norway spruce in
coastal areas of northern Sweden. However, as is suggested by the comparison
between the current results and those from a previous study in the interior
northern Sweden, spruce is more recommendable in coastal areas than in
interior locations from both the productivity and economic point of view. Yet,
market fluctuation, climate change and/or other social matters should also be
considered for selecting regeneration species.