SYLVICULTUKE. I 



II. Eastern sub-tropical forest. It shows evergreen Oaks, Mag- 

 nolias, Persea, etc., besides the Pines, the soil being too poor for the 

 formation of a large wintergreen broad-leafed forest. The winter 

 temperature averages 53 degrees Faht. ; precipitations are heavy; 

 relative humidity is 75 degrees. Sabal palmetto is a characteristic 

 weed. Bald Cypress and Cuban Pine are characteristic trees of the 

 region. Among the other Pines, the Long Leaf Pine is the most 

 important, associated in the north and west with Pinus clausa, 

 echinata, taeda, serotina, glabra. Liquidambar, Nyssa and Fraxinus 

 platycarpa occur in swamps at the edge of which southern White 

 Cedar frequently appears. 



III. Eastern winter bald forest of the moderately warm zone. 

 It is fringed at the south, north and east by a broad belt of Pines, 

 which belt connects this region at the south with the sub-tropical 

 forest, at the north with the Fir and Spruce forest of the moderately 

 cold zone. It is divided into a northern and a southern half by the 

 39th degree of latitude. Each half shows an Atlantic, a central 

 and a prairial sub-region. 



a. South Central sub-region. Traversed by the Mississippi, the 

 sub-region is characterized by high temperatures, large precipita- 

 tions and fine soil, which allow of the best development of broad- 

 leaved woods found in the world. Twenty-three Oak species, eight 

 Hickory species, two Walnuts, Buckeyes, Chestnut, Gums, Cotton- 

 woods, Yellow Poplar, Sycamore, Beech, Maple, Elm, Red Cedar, etc., 

 stand in a dense undergrowth formed by Dogwood, Kalmia, Rho- 

 dodendron, Hazel, Cherries, Hawthorn, Buckthorn, Witch Hazel, etc. 



In this sub-region the heavy seeded broad-leaved trees obtain 

 the maximum of size, quality and number of species at altitudes 

 running up to 3,000 ft. Higher up the number of species diminishes. 

 At 5,000 ft. only Red Oak, Chestnut, Beech, Buckeye, Sugar Maple 

 (resembling north central subdivision) are found, and at 6,000 ft. 

 the Spruces and Firs (southernmost sentinels of moderately cold 

 /one) set in. 



b. South Atlantic Sub-region. It comprises the Eastern foot- 

 hills of the Alleghanies (Piedmont Plateau) and part of the Coastal 

 Plain. Temperature 3% degrees Faht. less, soil poorer, precipita- 

 tions less abundant than in the South Central Sub-region, hence much 

 Pine (taeda, mitis, rigida, virginiana). Only ten Oak species; White 

 Cedar swamps; broad-leaved flora otherwise as in South Central, 

 but of rather inferior development. 



c. South Prairial Sub-region. Extending from the 92nd to the 

 102nd degree of longitude, the forest appears poorer than the annual 



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