Spruce (Sitka)
Picea sitchensis
Native range
Native to a narrow zone along the west coast of North America.
Provenance choice
Provenances from Queen Charlotte Islands (QCI) or Washington were
preferred in the afforestation programmes of the last century, but
genetically improved material is now widely available.
Site requirements
Adapted to a maritime climate with high atmospheric moisture. Sites
with less than 1000 mm rainfall per year should be avoided unless the
soil is moist; the species is therefore best suited to the upland parts
of north and west Britain. This is a pioneer or early successional
species of intermediate shade tolerance. It is tolerant of exposure and
cold hardy, but suffers from late spring frosts and air pollution. It
grows best on soils of poor or medium nutrient status with good moisture
status and will tolerate drained peats and gleys. Sensitive to heather
check on very poor soils, where it should be grown in mixture with pine
or larch. Under the exposed humid conditions of much of upland Britain it is a
high volume producer whose growth is mainly constrained by wind damage.
In much of western Britain, the greater warmth and higher rainfall
projected under climate change scenarios is likely to result in
increased growth of Sitka spruce, whereas in eastern Britain drier
conditions may increase the risk of drought crack and dieback.Pests and pathogens
In some years, Sitka spruce can suffer very heavy defoliation by the green spruce aphid (Elatobium) with a significant impact on growth.
The spruce bark beetle, Dendroctonus micans, accidentally
introduced from continental Europe and which now attacks Sitka spruce
has become established in many parts of Britain. A highly effective
biological control is in place to control this pest in the form of a
host-specific predatory beetle, Rhizophagus grandis. Another non-native beetle, the larger European spruce bark beetle (Ips typographus),
is a significant pest on Norway spruce in some European countries. So
far absent from Britain, it has the potential to damage Sitka spruce
should it ever establish.
Heterobasidion (Fomes root and butt rot) affects most
commercial conifers and Sitka spruce is no exception, although in this
species it primarily causes butt rot and only occasionally kills.
However, the impact in plantations growing on peaty soils, especially
under conditions of high rainfall, is low.Timber characteristics
Can range from a creamy white, to a darker medium brown. Also tends to exhibit a subtle pinkish hue in some instances. Heartwood is rated as being slightly resistant to non-resistant to decay. Use
Common uses include timber, boxes/crates, furniture, aircraft components, musical
instrument soundboards, boat-building (masts and spars), wind turbine
blades, and virtually any application where a wood material with a good
strength-to-weight ratio is needed.
The database contains ... with this species.
loading...
