OAK FAMILV 



and increase in productiveness as they grow older. The 

 entire family is especially subject to attacks of the gall-fly. 



Quercus belongs to the long-lived trees ; the life of some 

 species is believed to reach one thousand years. There are 

 of course no records of long life in America, but there are 

 oaks in England which are believed to have been old trees in 

 the time of William the Conqueror. Pliny mentions a Quer- 

 cus Ilex which was an old tree when Rome was founded and 

 which was still living in his time. In the United States the 

 largest specimens of the genus are found in the Mississippi 

 valley. 



Remains of oak trees are found far north of their present 

 home in the miocene and eocene rocks of North America. 



American oaks naturally divide themselves into groups 

 which are characterized by the shape of their leaves and the 

 time required to bring their fruit to maturity. 



The first division comprises those species whose leaves 

 have either rounded lobes or are sinuate toothed, or entire, 

 but are destitute of bristles. These bloom in the spring and 

 mature their acorns the same season. They are called 

 the White Oak Group, or the Annuals. The White, Post, 

 Bur, Swamp White, Chestnut, Yellow, and Chinquapin are 

 Annuals. 



The second division comprises those species whose leaves 

 have pointed lobes which terminate in bristles. These 

 bloom in the spring, but the acorn does not mature until the 

 autumn of the following year. They are called the Red Oak 

 Group, or the Biennials. The Red, Scarlet, Black, Spanish, 

 Pin, Bear, Black Jack, Shingle and Willow are Biennials. The 

 leaves of the Shingle and the Willow oak are destitute of 

 bristles, but the acorns mature the second year. 



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