40 BULLETIN 680^ U. S. DEPARTMENT OF AGEICULTUEE. 



GENERIC CHARACTERISTICS OF YEW TREES. 



The yews belong to a generic group technically known as Taxus. { 

 They comprise both trees and shrubs, and while as a group they are 

 very distinct from other Gymnosperms, they are not strikingly 

 distinct as species. For example, there is great similarity in the i 

 appearance, structure, and qualities of the wood of different species, i 

 and also in the general appearance and form of their foUage and j 

 fruit. The characteristics mainly rehed upon to distinguish the 

 different species are the shape of the plant, habit of growth, and 

 some minor differences in the form and color of the leaves. The 

 arborescent representatives of this group are world-renowned trees. 

 The wood of one species of yew tree inhabiting Europe, Asia, and 

 Africa was long used by ancient tribes for bows, wliich were the 

 most important implements of war. In modern archery the wood 

 of this yew tree still holds the highest rank among bow woods. 



The yews are evergreen plants, their leaves remaining on the 

 twigs for many years. In form the leaves are flat, narrowly lance- 

 shaped, and sharp-pointed. They are arranged somewhat spirally 

 on the branches, but by a twist at their bases they usually appear 

 to grow in two lines, on opposite sides of the twigs ^^ (PI, XIII). 



The male and female flowei-s of the yews are borne on different 

 trees (exceptionally, flowers of both sexes sometimes occur on 

 different branches of the same tree). Male or poUen-bearing flowers 

 are small, yellowish, budhke bodies produced singly and rather 

 abundantly on the under sides of the branches, while the much less 

 numerous female flowers, small greenish bodies, occur similarly on 

 the branches. The latter develop into fruits (PI. XIII, a), which^ 

 ripen in one season and usually fall to the ground shortly after 

 maturity. The ripe fruit ^^ is a thin-skinned berryhke body, with a 

 bright coral-red, sweetish, mucilaginous pulp, in which a single hard 

 seed appears to be embedded nearly to its point. The seed-leaves 

 are regularly two in number. 



The purple or brown bark of yews is very thin. The exceedingly 

 narrow-ringed, dense wood varies in color from a clear rose-red to 



56 The main vigorous shoots of the compact columnar forms of the European yew tree produce leaves 

 with a spiral arrangement, but the ordinary form of this tree bears leaves apparently in two lines. 



57 The seed and leaves of the common European yew tree ( Taxus baccata Linn.) are known to be deadly 

 poison to human beings and animals when eaten. It is believed that the poison resides in the seed and 

 also in the leaves, from both of which W. Marme obtained by chemical analysis a white, crystalline, 

 poisonous powder named "taxine." Symptoms of poisoning from this plant are semiunconsciousness, 

 cold clammy skin, convulsions, difficult, breathing, dilated pupils, and attempted vomiting. (U.S. Dis- 

 pensatory, sixteenth and nineteentheditions.) While nothing appears to be known concerning the effect of 

 eating the fruit and foliage of our native yews, the very close relationship of these to the European yew tree 

 would indicate that the seed and foliage of our yew trees are similarly poisonous and should, therefore, 

 be avoided. The sweetish pulp of yew fruits is not poisonous, for the mountaineers of northwestern 

 India are said to eat this part of the fruit of Taxus baccata, while cattle of the region are said to eat the 

 foliage and twigs of this plant without injury. It is probable, however, that most browsing animals 

 rarely eat enough of the foliage to get the deadly effect. (Fide Brandis, For. Fl. Brit. Ind. 541.) 



