LARCH, a genus (Loris) of coniferous trees characterized by a pyramidal habit of growth; small linear leaves arranged in dusters upon the older branches, singly and spirally upon the young twigs, often conspicuous pis tillate flowers which develop small, erect, glo bose or oblong cones, the attenuate scales of which are not deciduous at maturity. The species, of which there are about a dozen, are natives of the colder parts of the northern hemisphere. The best-known one in the United States is the American larch, hack matack or tamarack (L. laricina), which grows generally in wet, peaty soils and shallow swamps, or occasionally upon drier upland soils, from Hudson Bay to Pennsylvania, and west ward to Manitoba and Illinois. It attains a height of 60 or more feet, and has nearly horizontal branches. Its wood is hard and very durable, but light in proportion to its size. Being very straight and slowly tapering, the trunks are much used for telegraph poles, scaf fold-supports, fence-posts, railway-tiep, and in ship-building. It isless planted for ornamental purposes than the following species because its branches are less pendulous and less leafy.
The European larch (L. deeidua) grows usually upon dry uplands and a wide range of soils, but rarely in moist ground. Its range is from the mountains of southern Europe to the far north, where it is among the few hardy trees; in Asia it has a similar distribution. In height it exceeds the tamarack, often reach ing 100 feet, and since it is of rapid grbwth, and is used for an even larger number of pur poses than the preceding, it is often planted for commercial purposes, windbreaks and for ornament. The timber which is rich in resin
and is practically exempt from insect attacks is valuable for wet situations, It is little used for planks because it warps badly. Since it does not ignite readily and does not splinter it was largely used in wooden battle-ships. Its bark, which contains tannin, is somewhat used in preparing leather; its stern yields Oren burgh gum resembling gum arabic; and its leaves in warm climates exclude Branson manna, a sweetish, turpentine-flavored manna (q.v.).
The other species more or less resemble the foregoing in habit and uses. The most beauti ful and ornamental is probably L. leptolepis, a native of Japan. It attains height of 70 and 80 feet and is remarkable for the brilliant au tumn colors of its foliage. All the species except the Himalayan larch (L. griffithii), which seldom exceeds 40 feet in height, are hardy throughout the United States. The tim ful and ornamental is probably L. leptolepis, a native of the Pacific Coast region from Oregon northward, is considered the best yielded by coniferous trees. The tree is the largest of the genus, often reaching a height of 150 feet.
The only insect seriously harmful to the larch is a sawfly (Nematus erichsonii), whose young hatch in early summer from eggs previ ously inserted into the young shoots, and im mediately begin feeding upon the leaves. This pest is occasionally sufficiently numerous to de foliate large tracts of forest.