HEMLOCK , the plant Conium maculatum, probably the Heb. ראש or רוש (rosh) of the Bible. Rosh is mentioned 11 times in the Bible, five together with la'anah ("wormwood"), as a simile for wickedness and for something evil and poisonous. The Authorized Version renders rosh as "gall," i.e., snake venom, but the Bible explicitly refers to it as a plant that puts out roots (Deut. 29:17) and flourishes in the fields (Hos. 10:4). Its poisonous fruits are called "grapes of rosh" (Deut. 32:32; which by transference was applied there to snake venom). It is a tall plant with which the elegist of the Book of Lamentations (3:5) sees himself surrounded and whose poison he fears. From this plant a poisonous potion was prepared (Jer. 8:14, 9:14). On occasion it was eaten, the psalmist (Ps. 69:21–22) describing the wicked surrounding him as coming to comfort him in his mourning and, instead of the mourner's meal, giving him rosh to eat. There is no exegetical or philological evidence by which to identify the scriptural rosh. A number of poisonous plants have been suggested for it as, for example, the colocynth. Among those deserving consideration, is the poppy (Papaver somniferum; see *Spices), for whose round seeds the name rosh ("head") is apt, and from the juice of which opium is prepared. This is mentioned in the Jerusalem Talmud (Av. Zar. 2:2, 40d) as a dangerous substance. Others have identified rosh with the plant Hyoscyamus aureus, which contains a poisonous and intoxicating juice. In Aramaic it is called shikhrona ("intoxicator"), a term also found in Josephus (Ant. 3:172ff.). The latter compares the crown above the gold plate of the high priest (Ex. 28:36) to its calyx, describing this plant in all its detail, the first morphological description of a plant in ancient Jewish literature.
Of all those proposed identifications the most reasonable is hemlock (Conium), a plant of the family of Umbelliferae, with a large inflorescence like an umbrella for which the name rosh ("head") is apt. It grows wild in fields and on the roadside in various parts of Israel. It contains a powerful poison.
Loew, Flora, 2 (1924), 364–70; 3 (1924), 48; J. Feliks, Olam ha-Ẓome'ah ha-Mikra'i (19682), 197–201. add. bibliography: I. Jacob and W. Jacob, in: abd, 2:816; J. Tigay, jps Torah Commentary Deuteronomy (1996), 398, n. 35.
hemlock, any tree of the genus Tsuga, coniferous evergreens of the family Pinaceae (pine 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. 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 yew. The poison hemlock and water hemlock are herbs of the family Umbelliferae (carrot family) of the division Magnoliophyta. True hemlock is classified in the division Pinophyta, class Pinopsida, order Coniferales, family Pinaceae.
poison 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. Although native to the Old World, it is now naturalized and common in parts of the United States. The poisonous principle (the alkaloid coniine) causes paralysis, convulsions, and eventual death. Poison hemlock was used in ancient Greece in executions; a famous example was the philosopher Socrates. The related water hemlock (any species of Cicuta) is similar in appearance and as poisonous. C. maculata, called also musquash-root, spotted cowbane, and beaver poison, is the common species of E North America. The evergreen trees called hemlock are unrelated. Poison hemlock is classified in the division Magnoliophyta, class Magnoliopsida, order Apiales, family Umbelliferae.
hem·lock / ˈhemˌläk/ • n. 1. a highly poisonous European plant (Conium maculatum) of the parsley family, with a purple-spotted stem, fernlike leaves, small white flowers, and an unpleasant smell. ∎ a sedative or poisonous potion obtained from this plant. 2. a coniferous North American tree (genus Tsuga) of the pine family with dark green foliage that is said to smell like the hemlock plant when crushed, grown chiefly for timber and pulp production.