76 NATURAL HISTORY OF THE FARM 
and structure and color of the pith will often furnish good 
characters. 
One who is learning them should employ his senses of 
touch, taste and smell as well as his sight. The toughness 
and pliancy of hickory twigs are revealed to our fingers. By 
biting twigs, distinctive flavors may be discerned in most 
twigs. Tulip tree is bitter, and sweet birch is deliciously 
aromatic. The buds of linden are mucilaginous when 
chewed. The twigs of walnut and sassafras have a smell that 
is instantly recognizable. There is no difficulty at all about 
knowing the principal kinds of trees if one will take the 
trouble to note their characteristics. 
Study 9. Recognition Characters of Deciduous Trees in 
Winter 
The object of this study is to learn to recognize a dozen or 
more common native trees. The apparatus needed by the 
student is only a lens and a knife: collective use may per- 
haps be made of an axe or a hooked pole. 
The program of work should consist of a short excursion 
among the trees, first where growing in the open, to observe 
their outlines, and later, into the woods. The species 
selected for examination will be studied as to the characters 
indicated by the column headings of the table on pages 74 
and 75. 
The record of this study will consist in: 
1. The completed tabulation. 
2. Simple outline sketches of twigs: 
(a) Of ash and birch or elm. 
(b) Longitudinal sections of walnut or butternut. 
(c) Cross sections of oak and linden. 
