IOO 



Trees, Stars, and Birds 



sometimes somewhat obliquely, and the edges of the 

 annual rings running lengthwise of it. 



If we cut the trunk lengthwise but not near the center, 

 we make a tangential section. A tangential section 

 exposes the ends of the pith rays and cuts obliquely 

 through the annual rings. In such a section the annual 

 rings appear wider than in a radial section. 



In a board the transverse section shows at the ends ; 

 the flat surfaces of boards show either a radial or a tan- 

 gential section or a section intermediate between them. 

 The patterns in an ash board. Find if possible an 

 ash board or a desk or other 

 piece of furniture made of ash. 

 The annual rings will show 

 plainly because, where conditions 

 are favorable, ash grows fast and 

 makes wide rings and also be- 

 cause ash wood is ring-porous 

 and there is a strong contrast 

 between the springwood and the 

 summerwood. If the wood has 

 been finished, the springwood 

 will be darker because the large 

 pores are filled with the dark 

 filler. 



In a radial section the edges 

 of the annual rings will be seen 

 as lines lengthwise of the wood 

 (Fig. 62). In a tangential .. sec- 

 tion the pattern is more com- 

 plicated, but it can be understood 



American Forestry 

 FIG. 62. An ash board. 

 Can you explain the mark- 

 ings in the board ? 



