Fir, a popular name often applied to all the true Conifers (Abietince) or restricted to the spruces (Picea) and silver firs (Abies). These two genera agree, and are distinguished from pines and larches by having their narrow, needle-like leaves arranged singly - i.e. not in tufts. Their cone-scales also do not become thickened into a woody "apophysis" at their apex. They are conical trees with regular pseudo-whorls of branches, which themselves branch horizontally so as to form a "spray." In Picea the ripe cones hang downwards and fall off whole, and the leaves are arranged all round the shoots: in Abies the cones are erect and their scales fall off separately, whilst the leaves are in two distinct rows. Of the former genus, the most important is the Norway Spruce (q.v.), P. excelsa, other species being the Black and White Spruces (P. nigra and P. alba) of north-eastern North America. Of the latter, the Silver Fir (-4. pectinata) is the type, other species being the Balsam Fir of Canada (A. balsamea), A.pinsapo, A.pordmanniana and other ornaments of our parks and gardens. The Silver Fir, a native of Central Europe, has two broad white lines along the under surface of its leaves. The wood is less resinous than spruce, but "Strasburg turpentine" exudes from its bark.
From A. balsamea Canada balsam is similarly obtained. The Hemlock Spruce (q.v.) (Tsuga canadensis) of eastern Canada and the Douglass Spruce or Oregon Pine (Pseudo-tsuga douglasii) of the Rocky Mountains, a valuable timber-tree, hardy in the British Isles,' belong to allied genera. ["Balsams, Pine, Spruce.]