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THE OAKS— QUERCUS, (Tourn.) L. 



This genus, which consists almost entirely of trees, comprises about 

 300 species in the world. The Oaks are world famous on account 

 of their wide distribution, physical sturdiness, great strength, and 

 the high commercial value of their wood. Most of them attain a 

 great age and are aggressive competitors in the constant struggle 

 which is going on in the forest. They can be reproduced by sprouts 

 or by seed, naturally or artificially. Their modesty recommends 

 them from a silvicultural ix)iut of view since they will grow in habi- 

 tats which are moist or dry, sterile or fertile, cold, temperate or 

 tropical, at low altitudes or at high altitudes up to the timber line. 

 They prefer the temperate climate. 



Economically this genus is one of the most important among the 

 trees. Its wood is used extensively and is especially adapted for 

 high grade work. The bark is rich in tannin, while that of a few 

 European species is used for cork. The galls which are caused by 

 insect stings are also often rich in tannin. The nuts are used in 

 some places as food for man and swine, and occasionally when 

 roasted form a substitute for coffee. 



The leaves are alternate, simple, and usually slied in autumn. A 

 division of the Oaks known as the Evergreen or Live Oaks, sheds 

 the leaves at the end of the second or third season. The flowers, 

 stamiuate and pistillate, appear on different parts of the same tree 

 and often on different parts of the same branch. The staminate or 

 male flowers are shiall and arranged singly on a long slender and 

 drooping anient which emerges from the buds on the twigs of the 

 previous year's growth. The pistillate or female flowers are small, 

 inconspicuous, urn-like bodies which appear singly or in groups from 

 the base of the developing leaves of the season. The flowers are 

 fertilized by the wind and develop into a nut-like fruit known as an 

 acorn. The fruit is distinctive in having a scaly, often bristly cup 

 separated from the thin-shelled nut which it partly or almost wholly 

 encloses. In autumn the nuts may fall to the ground while tlie cups 

 persist on the tree, or the nut and cup may fall together. The acorns 

 may germinate immediately after falling to the ground, but 

 usually they remain dormant until the following spring. The 

 seed-leaves of the nut remain in the shell and furnish nourishment 

 to the developing seedling. A long tap root is characteristic of an 

 oak seedling. This makes them difficult to transplant in a nursery 

 or to plant in the place where they are to develop into large trees. 

 A large part of the first two seasons' growth of many of our Oaks 

 is concentrated mostly in the development of a root system. The 



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