Picea mariana - black spruce

Black spruce grows in North America in a broad belt from Alaska to Newfoundland, and as far south as the Great Lakes. In the southern parts of its range it grows mainly on mires, further north also on drier soils. This is a small slim tree with a narrow cylindrical crown. Needle colour varies: dark green, blue-green, or grey-green. The cones are small and ball-shaped, often growing in tight bunches near the crown, and remaining on the tree for several years. Black spruce can regenerate throughout most of its range by layering from branches in contact with the ground.

Black spruce grows successfully in Finland, but is a short-lived species. At Mustila, all the old plantings have died from insect attack. New plantings have been made from the 1990s onwards, e.g. in the spruce collection area in the western part of the Arboretum. Using a variety of seed sources, it is possible to find trees which are suitable to local conditions and less susceptible to insect attack. West of the Arboretum, on land belonging to Mustila Manor, there is an old plantation of black spruce from New Hampshire seed which is still in good condition.

The contribution of black spruce to Finnish forestry is limited to its use in exceptional conditions, for example plantings on cold peat bogs. But it is a useful addition for landscape use, being hardy, dense, tough and moderate in size. It has also been used occasionally as a Christmas tree in recent years.