APPENDIX. 301 



a. Pith rays small to very small, but quite distinct, 

 a/ Wood hard. 



a." Color reddish white, with dark reddish tinge in outer sum- 

 mer wood MAPLE. 



6." Color white, without reddish tinge HOLLY. 



6.' Wood soft to very soft. 



a." Pores crowded, occupying nearly all the space between pith 

 rays, 

 a.'" Color yellowish white, often with a greenish tinge in 



heart-wood TULIP POPLAR. 



CUCUMBER TREE. 

 &."' Color of sap-wood grayish, of heart-wood light to dark 



reddish brown SWEET GUM. 



&." Pores not crowded, occupying not over one-third the space 

 between pith rays; heart-wood brownish white to very light 



brown BASSWOOD. 



6. Pith rays scarcely distinct, yet if viewed with ordinary magnifier, 

 plainly visible. 

 a/ Pores indistinct to the naked eye. 



a." Color uniform pale yellow; pith rays not conspicuous even 



on the radial section BUCKEYE. 



&." Sap-wood yellowish gray, heart-wood grayish brown ; pith 



rays conspicuous on the radial section SOUR GUM. 



&/ Pores scarcely distinct, but mostly visible as grayish specks on 



the cross-section; sap-wood whitish, heart- wood reddish. . BIRCH. 



D. Pith rays not visible or else indistinct, even if viewed with magnifier. 



1. Wood very soft, white, or in shades of brown, usually with a silky 



luster COTTONWOOD (POPLAR) . 



ADDITIONAL NOTES FOR DISTINCTIONS IN THE GROUP. 



Cherry and birch are sometimes confounded, the high pith rays on the 

 cherry on radial sections readily distinguishes it; distinct pores on birch and 

 spring wood zone in cherry as well as the darker vinous-brown color of the 

 latter will prove helpful. 



Two groups of birches can be readily distinguished, tho specific distinc- 

 tion is not always possible. 



1. Pith rays fairly distinct, the pores rather few and not more abundant 



in the spring wood : wood heavy, usually darker, 



CHERRY BIRCH and YELLOW BIRCH. 



2. Pith rays barely distinct, pores more numerous and commonly forming 

 a more porous spring wood zone; wood of medium weight, 



CANOE OR PAPER BIRCH. 

 The species of maple may be distinguished as follows: 



1. Most of the pith rays broader than the pores and very conspicuous. 



SUGAR MAPLE. 



