68 



ECONOMIC BOTANY OF ALABAMA. 



ers of the same class, turns nearly at a right angle to its 

 former course, leaves the comparatively soft Paleozoic 

 rocks, and cuts across the western end of the Piedmont 

 region for a distance of about fifty miles, resuming its 

 original direction immediately upon crossing the fall-line 

 at Wetumpka. 



All the rivers and creeks are full of rocky shoals 

 (which are being utilized more and more for water- 

 power), and are navigable only for skiffs or other small 

 boats. The larger streams are muddy most of the time, 

 and fluctuate considerably, but they were undoubtedly 

 clearer and more constant before so much of the forest 

 was cut away. 



Climate. — The climatological data for Goodwater and 

 Opelika show that the average temperature of this part 

 of Alabama is about 63°, and the length of the growing 

 season about 235 days. The average precipitation is 

 about 52 inches, and winter and spring are a little wetter 

 than summer and fall, as in all the regions previously 

 discussed. 



Forest types. — The principal forest types are dry 

 woods on the ridges, rich woods on north slopes and 

 in ravines, wet woods along branches, and strips of river- 

 bank trees on the larger streams. The driest soils have 

 the largest proportion of pines. Long-leaf pine seems to 

 be entirely absent from the central portion of Chambers 

 County, but becomes more and more abundant with in- 

 creasing distance from that center of rich soil. 



Fire is frequent in the long-leaf pine forests, as usual, 

 moderately so among the short-leaf pines, and rare in 

 other types of forest. 



LIST OF TREES. 



