1911 Encyclopædia Britannica/Tamarisk

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TAMARISK. The genus Tamarix gives its name to a small group of shrubs or low trees constituting the tamarisk family Tamaricaceae. The species of tamarisk and of the very closely allied genus Myricaria grow in salt-deserts, by the sea-shore, or in other more or less sterile localities in warm, temperate, subtropical, and tropical regions of the eastern hemisphere. Their long slender branches bear very numerous small appressed leaves, in which the evaporating surface is reduced to a minimum. The flowers are minute and numerous, in long clusters at the ends of the branches or from the trunk. Each has 4-5 free sepals, and as many petals springing with the 4-10 stamens from a fleshy disk. In Tamarix the stamens are free, while in Myricaria they are united into one parcel. The free ovary is one-celled, with basal placentas, and surmounted by 3-5 styles. The fruit is capsular, and contains numerous seeds, each usually with a long tuft of hairs at one end. The great value of these shrubs or trees lies in their ability to withstand the effects of drought and a saline soil, in consequence of which they grow where little else can flourish. On this account the common tamarisk, T. gallica, is planted on sea-coasts, and affords shelter where none other could be provided. Some species produce galls, valued for their tannin, while the astringent bark of others has occasionally been used for medicinal purposes. The ashes of the plant, when grown near the sea, are said to contain soda. For tamarisk manna, see Manna.