The development of pine cones in the Scots pine. (1) In the spring the dark-colored branches of the pine put out new green shoots. Here are two shoots that have grown in the New Year. (2) The pine had two kinds of flowers: one with stamens, which produce the pollen, and one bearing ovules which receive the pollen and later develop into seeds.
A conifer is a cone-bearing tree, generally evergreen. Conifers are classified as Phanerogams, because they reproduce by means of flowers, and are included in the order Gymnophermae (see gymnosperm), bearing flowers without a corolla and seeds not enclosed by fleshy fruit. Familiar conifers are the Scots pine, yew and juniper (these two being unusual in not bearing true cones), Norway spruce, silver fir, larch, Cypress, cedar and the American redwoods and sequoias, which are the largest trees in the world,, reaching heights of up to 99 meters (325 feet).
Pines are extremely useful trees. Among other things they produce resin, which can be collected by making incisions in the bark so that the resin oozes out. A maritime pine 60 to 70 years old can produce about 15 pounds of resin a year. By distilling the resin, turpentine and rosin or colophony are obtained. From turpentine varnishes and furniture and linoleum polish are made, and rosin is used in soap manufacture.
Timber from pines is used in building, for telegraph poles and other purposes, and a great deal of wood is pulped to make paper. The branches make excellent firewood.
The seeds of the stone pine are edible and are used by confectioners.
Pine trees found in Britain
Scots pine (Pinus silvestris)
The only native British pine tree. Great forests of this tree once grew in Scotland, but they have almost all been cut down. The trunk is slender and reddish in color and when the tree is mature only the topmost branches bear leaves. The lower branches die and fall as the tree grows.
Mountain pine (Pinus montana)
This native of Europe is found mainly in the Dolomite Mountains in northern Italy. It may grow as a tree of over 70 feet or as a bush, creeping along the ground, and can ten cover an area 50 feet in diameter. Its resin contains an oil that is used in medicine.
Black pine (Pinus nigra)
A native of Central Europe and the countries round the Mediterranean. It is distinguished from the Scots Pine by its dark color and grey (never red) bark.
Cembran or Swiss stone pine (Pinus cembra)
This is a native of northern Siberia and the high Alps. The fine needles, clustered in fives, and the large wingless seeds distinguish it from other European pines.
Stone pine (Pinus pinea)
A native of the Mediterranean countries and grown only as an ornamental tree in Britain. The trunk is reddish and scaly and branches only at the top, giving the tree an umbrella-like appearance. The edible seeds, under the name of pine kernels, are important for use in confectionery.
Maritime or cluster pine (Pinus pinaster)
Another Mediterranean species which grows best near the sea. In Britain it is planted in south and west England and flourishes particularly near Bournemouth. The cones are large and the tree yields resin more abundantly than any other pine.
European silver fir (Abies pectinata)
A native of the mountains of southeastern and central Europe and not really at home in the British climate, the Silver Fir has nevertheless been extensively planted in Britain both for timber and as an ornamental tree. The Latin name 'pectinate' means 'comb-like' and refers to the arrangement of the needles on the shoots.
Norway spruce (Picea excels)
Not a native of Britain, but by no means a recent introduction, as most of our foreign conifers are; Spruce was grown here in mediaeval times, probably before 1500. It is now one of our most important trees in economic forestry, and as Christmas trees the young trees are familiar to everyone. It is said to live up to 400 years.
Larch (Larix deciduas)
Introduced as an ornamental tree in the sixteenth century, the European Larch has been of importance in British forestry, but the hardier Japanese larch (Larix leptolepis) is taking its place. Larches are exceptional among conifers in losing their leaves in the winter. The timber is especially useful for under-water construction.