The Trees of Vermont 203 



KEY TO THE WOODS OF VERMONT 



In the following key, the Roman type calls attention to characters which 

 may readily be distinguished by the naked eye or by the use of a hand lens, 

 and should not be interpreted as indicating more important characters. The 

 italics represent characters that can be studied only with a compound 

 microscope. 



The word in parenthesis indicates the section, cross-, radial-, tangential- 

 or longitudinal-, which shows the point in question to greatest advantage. 



a.' Pores (cross) visible and conspicuous, at least with magnifier, i. e., 

 wood composed of three to sLv kinds of cells, ivhich are not uniform 

 in structure and usually not arranged in definite radial rows; 

 resin ducts and resin cells (cross) absent; rays (cross) for the 

 most part conspicuous. 



h. Growth rings (cross) defined by zones of large pores in the 

 spring wood alternating with the denser summer wood ; pores in 

 summer wood small, or few and scattered. 



c. Rays (cross), or part of them, broad, easily distinguishable 

 by the naked eye at three feet distance ; on close inspection, 

 rays of two kinds, broad and fine. 



d. Pores (cross) abruptly diminishing in size from spring 

 wood to summer wood; tyloses (longitudinal) present, 

 usually abundant in all large pores, 

 e. Pores (cross) of spring wood 1-3 rows deep. 



/. Pores (cross) of summer wood arranged chiefly in 

 single, radial rows, seldom joined tangentially, the rows 

 extending to the periphery of the growth rings, 



Quercus bicolor, 

 ff. Pores (cross) of summer wood arranged chiefly in 

 double, radial rows, often joined tangentially, the rows 

 rarely extending to the periphery of the growth rings. 

 g. Radial rows of summer-wood pores (cross) rela- 

 tively wide ; large rays about ^^ inch apart, 



Quercus macrocarpa. 

 gg. Radial rows of summer- wood pores (cross) rela- 

 tively narrow ; large rays about y^ inch apart, 



Quercus alba. 

 ee. Pores (cross) of spring wood 3-5 rows deep, 



/. Radial rows of small pores (cross) chiefly in several 

 rows, becoming wider toward the periphery of the 

 growth rings ; walls of summer-wood pores thin, 



Quercus prinus. 



1 aa. See page 211. 



