hemlock(redirected from Hemlock (disambiguation))
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hemlock,any tree of the genus Tsuga, coniferous evergreens of the family Pinaceae (pinepine,
common name for members of the Pinaceae, a family of resinous woody trees with needlelike, usually evergreen leaves. The Pinaceae reproduce by means of cones (see cone) rather than flowers and many have winged seeds, suitable for wind distribution.
..... Click the link for more information. family) native to North America and Asia. The common hemlock of E North America is the eastern hemlock, T. canadensis, an ornamental tree (sometimes cultivated as a hedge) with small cones and short, dark green leaves so arranged as to give the branchlets a flattened appearance. Found from the S Appalachians to N Wisconsin and SE Canada, the tree has been highly valued as a source of tanbark but is now seriously reduced in number. Its wood is soft and light. The Carolina hemlock, T. caroliniana, found on the slopes of the S Appalachians, is grown as an ornamental. Both trees are threatened by the hemlock woolly adelgid, an insect that is native to E Asia and was first found in their range in the 1960s. A hemlock that is a hybrid of the Carolina hemlock and the Chinese hemlock, T. chinensis, and is resistant to the woolly adelgid has been developed for the horticultural trade. The western hemlock, T. heterophylla, is the tallest tree of the genus. Found along the coast from S Alaska to N California, it has more valuable wood, which is used in construction work. The mountain hemlock, T. mertensiana, has a similar range but is found inland S of Canada. Both western species are grown as ornamentals. The ground hemlock is a species of yewyew,
name for evergreen trees or shrubs of the genus Taxus, somewhat similar to hemlock but bearing red berrylike fruits instead of true cones. Of somber appearance, with dark green leaves, the yew since antiquity has been associated with death and funeral rites.
..... Click the link for more information. . The poison hemlockpoison hemlock,
lethally poisonous herbaceous plant (Conium maculatum) of the family Umbelliferae (parsley family). It has rank, finely divided foliage, flat-topped clusters of small white flowers, and a hollow, purple-mottled stem.
..... Click the link for more information. and water hemlock are herbs of the family Umbelliferae (carrotcarrot,
common name for some members of the Umbelliferae, a family (also called the parsley family) of chiefly biennial or perennial herbs of north temperate regions. Most are characterized by aromatic foliage, a dry fruit that splits when mature, and an umbellate inflorescence
..... Click the link for more information. family) of the division MagnoliophytaMagnoliophyta
, division of the plant kingdom consisting of those organisms commonly called the flowering plants, or angiosperms. The angiosperms have leaves, stems, and roots, and vascular, or conducting, tissue (xylem and phloem).
..... Click the link for more information. . True hemlock is classified in the division PinophytaPinophyta
, division of the plant kingdom consisting of those organisms commonly called gymnosperms. The gymnosperms, a group that includes the pine, have stems, roots and leaves, and vascular, or conducting, tissue (xylem and phloem).
..... Click the link for more information. , class Pinopsida, order Coniferales, family Pinaceae.
the common name for North American species of trees of the genus Tsuga of the family Pinaceae. The trunk has deeply furrowed exfoliative strips of bark. The crown is conical. The needles are flat and linear-lanceolate. Hemlocks are hygro-philous but do not tolerate swamping; they do not grow well in shady areas or in regions having low humidity. They tolerate trimming well and are planted singly or in groups as barriers or to line streets. The lightweight wood is not very strong and lacks resin ducts; it is used to manufacture paper and boxes. The most common species is the eastern hemlock (Tsuga canadensis).