SILVICULTURE OF EASTERN FRANCE 



513 



Climate. — The climate resembles in many ways that of the vicinity 

 of Washington, D. C. The annual rainfall is about 35 inches ; with the 

 drier season in the summer and snow in the winter becoming 5 to 10 

 inches deep, but rarely lasting as a cover for the ground more than a 

 week or two at a time. Summer temperatures are much less extreme. 

 The relative humidity is high and fogs are frequent. 



In the so-called mountain forests under consideration, the difference 

 in elevation and climate cause no differentiation of types, and the 

 topography and aspect cause only minor variations in the proportion of 

 species. 



Type. — The type may be called the beech-oak-hornbeain type, since 

 these are the predominant and characteristic species. In the larger val- 

 ley bottoms there is also a hazel-alder type, with an overstory of oak 

 and ash, which may be mentioned in passing, but will not be further 

 considered. 



Within the beech-oak-hornbeam type, a variety of species occur; they 

 are indicated, together with their relative silvical characteristics, in the 

 following table : 



Differences in topography, aspect, and soil depth and moisture ac- 

 count for the variations within the type. On the draw bottoms and 

 lower slopes, ash becomes relatively abundant both in the coppice and 

 the overstory. Oak and mountain ash are hardly noticeable. On the 

 north and east slopes with moderately deep, moist soil, beech may 

 form a nearly pure overstory, with hornbeam predominant in the cop- 



^ Species. — Beech, Fayus sylvatica; oak, Qncrcus pcdiinculata; hornbeam, 

 Carpinus betulus; ash, Fraxinns excelsior; maple, Acer campestris ; mountain 

 ash, Sorbns aria. Snrhus tnrminalis, Sorbus auctiparia, Sorbus domestica; lin- 

 den, Tilxa parzn folia; cherry, Pruinis domestica; pear, Pints communis; apple, 

 Mains communis. 



