Picea

The name red spruce derives from the generally reddish brown appearance of the forest in its natural range, where in the eyes of local foresters it is distinguishable from the darker black (P. mariana) and lighter white (P. glauca) spruces. All three species grow in the same area of eastern North America. The range of the red spruce is the most Atlantic of the three. At its southern limit it grows as a mountain species on the upper slopes of the Appalachians.

The red spruce has been grown at Mustila since 1914. The oldest plantation was from seed of New Hampshire provenance, and was one of the most successful trials of American spruce made at Mustila. It thrived for almost a century until the whole stand died in the years 2009-2011. An individual old specimen can still be found in the Ropakko grove, where its typical profile is easily distinguished, especially in winter. New red spruce plantings were made in 2010 towards Nokkala, using two separate Canadian provenances.

The alternative name for this species honours Peter von Glehn, a botanist of German-Baltic origin who worked in Russia. It has a long history at Mustila, having been among the species planted as seedlings from seed sent from Japan in 1908 by the Dane Johannes Rafn, the Arboretum’s ”court purveyor”. The stand, now over 100 years old, is still in fine condition, which can’t be said of many of the exotic spruce planted at Mustila. However, the visitor is more likely to see the Glehn spruce as a young tree, in the 1995 plantings along the Northern Slope road.

Glehn spruce is a maritime species, starting seasonal growth over 2 weeks later than the native species (Picea abies). This protects the tender new growth from late spring frosts. As an ornamental garden tree it has been almost totally forgotten, unfortunately, nor has it even been tried as a Christmas tree. The structure of its branches is beautiful, gently uplifted in the crown as with many east-Asian trees, while the short, deep green needles, which have a slightly bluish tinge, are attractively dense and bushy. The sturdy trunks are red-brown. For anyone who enjoys the beauty of conifers it is worth the slight effort involved in following the seldom-used path along the southern edge of the larch plantation to the north-east corner of the White-Cedar Valley, where the old Glehn spruce grow at the edge of the forest opening.

The white spruce of the South Dakotan Black Hills differs enough from its relatives that it is usually given its own varietal name. The cones are shorter, the needles a beautiful blue-grey, and the whole habit of the tree is tight and extremely attractive, which is why it is used in America as a Christmas tree and a garden ornamental.

Because this local variety could also be suitable for small gardens in Finland, a large batch of seeds was ordered in 1993 from seed collector Dean Swift. The collection was made in the Black Hills National Forest at between 1200-1500m elevation, where the climate is very cold but rather more continental than in Finland. The resulting trees have been growing since the year 2000 in a small stand in the western part of the Arboretum. After some early problems they have developed into densely beautiful young trees with bluish needles. It seems that the Black Hills spruce, adapted to a continental climate, is best suited to the eastern parts of Finland. To date, their northern hardiness limit is undefined.