THE CHARACTERISTICS OF TREES. 23 



is an error with no foundation whatever. As the Avood 

 and leaves ripen in the autumn, the roots ahnost cease 

 to imbibe crude sap, and for a while the entire structure 

 appears to part with moisture, and doubtless does so 

 through the exhalations from the ripening leaves, buds, 

 and smaller twigs, but as warm weather again approaches, 

 and the temperature of the soil increases, the roots again 

 commence to absorb crude sap and force it upward, 

 where it meets soluble organized matter changing its 

 color, taste, and chemical properties. 



If this was not the case, we could not account for the 

 saccharine properties of the sap of the maple, or for the 

 presence of various mucilaginous and resinous constit- 

 uents of the sap of trees in early spring, because we 

 find no trace of such substance in the liquids or crude 

 sap as absorbed by them from the soil. If the growth of 

 a tree continues all the season without check, there will 

 be one well defined ring of new wood deposited over the 

 entire outer surface; but in some instances drouths 

 check growth in mid-summer, and these being followed 

 by heavy rains and warm weatlier, a second growth often 

 takes place, producing a second deposit of new wood. 

 In what may be termed cool climates, it seldom occurs 

 that a second deposit is of sufficient thickness to be dis- 

 tinguished from the first, and as a rule the age of a tree 

 may be determined by the annular rings, provided, of 

 course, they are sufficiently distinct to be counted. 



THE BUDS OF TREES. 



For all practical purposes the buds of trees may be 

 divided into four classes, the terminal, axillary, acces- 

 sory, and adventitious. What are usually termed fruit 

 buds by horticulturists, may be placed in the second 

 division, because they have not generally a fixed charac- 

 ter, but are analagous to a leaf bud, and while under 



