In the economy of the northern nations of Europe P. sylvestris is an important tree. In Scandinavia and Russia houses are chiefly constructed of its timber; and log-huts are made of the smaller trunks and lined and roofed with the bark. The inner bark is twisted into ropes, and, in times of scarcity, is kiln-dried, ground up and mixed with meal.
Vast numbers of Scotch firs are raised in nurseries for artificial planting; the seed is sown in the spring, being just covered with earth, and the seedlings transplanted in the second year into rows for further culture, or taken direct to the seed-bed for final plant ing; sometimes the seed is sown where the trees are intended to grow. A plantation of young Scotch firs requires frequent and careful thinning as the young trees increase in size; but pruning should be avoided as much as possible, except for the removal of dead wood.
In Great Britain P. sylvestris is subject to many insect depreda tions : the pine-chafer, Hylurgus piniperda, is destructive in some places, the larva of this beetle feeding on the young succulent shoots, especially in young plantations; the fir-weevil, Hylobius abietis, eats away the bark, and numerous lepidopterous larvae devour the leaves; the pine-sawfly is also injurious in some sea sons. The removal of all dead branches from the trees and from the ground beneath them is recommended, as most of these insects lay their eggs in the decaying parts of the bark and among the dead leaves.
In common with other pines, P. sylvestris is subject to the at tacks of various fungi. Trarnetes radiciperda attacks the roots and penetrates to the stem, causing rotting of the wood. The dis ease is difficult to eradicate, as the mycelium of the fungus travels from root to root in the soil. Rotting of the wood at the base of the trunk is also caused by Agaricus melleus, which spreads in the soil by means of its long purple-black, cord-like mycelial strands known as Rhizomorpha. Much damage is often caused by species of Peridermium, which often invade the soft portions of the inner bark to such an extent as to "ring" the stem or branch, or to cause an abnormal formation of turpentine which soaks into the wood and stops the upward passage of water; this causes the parts above the diseased area to perish.
Plantations in England are generally ready for final cutting in from 6o to 70 years, and many are cleared at a much earlier stage of growth, especially when protected from injury by pests. In
England the pine is largely employed as a "nurse" for oak trees, its conical growth when young admirably adapting it for this purpose; its dense foliage renders it valuable as a shelter tree for protecting land from the wind ; it stands the sea gales better than most conifers, but will not flourish on the shore like some other species. This pine is planted for ornament in the Eastern United States where it has become sparingly naturalized ; it has also proved of value in afforesting treeless lands, as in the National forest in western Nebraska.
Large quantities of turpentine are extracted from this pine in Sweden and Russia by removing a strip of bark, terminating below in a deep notch cut in the wood, into which the turpentine runs, and from which it is scooped as it accumulates; but the product is not equal to that of the silver fir and other species. Tar is prepared largely from P. sylvestris ; it is chiefly obtained from the roots.
Closely allied to the Scotch pine, and perhaps to be regarded as a mere alpine form of that species, is the dwarf P. Pumilio, the "krummholz" or "knieholz" of the Germans—a recumbent bush, generally only a few feet high, but with long zigzag stems, that root occasionally at the knee-like bends where they rest upon the ground. The foliage much resembles that of the Scotch fir, but is shorter, denser and more rigid; the cones are smaller but simi lar in form. Abounding on the higher slopes of the Bavarian and Tirolese Alps, it is a favourite shelter for the chamois; the hunt ers call it the "latschen," from its recumbent straggling habit.
The red pine, P. resinosa, of south-eastern Canada and the northern border of the United States from Minnesota eastward (so called from the colour of its bark), is a tree sometimes 120 ft. high, with a trunk 3 ft. or more in diameter. The somewhat glau cous leaves form dense tufts at the ends of the branches, and are 4 or 5 in. long; the ovate blunt cones are about half that length. The tree is of quick growth and the wood strong and resinous, but it is less durable than Scotch fir although much employed in ship building.