30 TREES OF THE NORTHERN UNITED STATES 



growth then form and often become quite large before 

 autumn. 



There are many examples among the smaller plants, 

 but rarely one among the trees, of indefinite anmial 

 growth; that is, the plant puts forth leaves and forms 

 stems throughout the whole growing-season. The' com- 

 mon Locust, the Honey-locust, and the Sumacs are illus- 

 trations. 



BUDS. Buds are either undeveloped branches or un- 

 developed flowers. They contain within the scales, which 

 usually cover them, closely packed leaves ; these leaves 

 are folded and wrinkled in a number of different ways 

 that will be denned at the end of this chapter. 



POSITION AND NUMBER. While the axils of 

 the leaves and the ends of the stems are the 

 ordinary places for the buds, there are many 

 peculiarities in regard to their exact position, 

 number, etc., that render them very interesting 

 for winter study. Sometimes there are several 

 to the single leaf. In the Silver Maple there are 

 buds on each side of the true axillary one ; these 

 are flower-buds, and during the winter they are 

 larger than the one which produces the branch. 

 The Butternut (Fig. 14) and the Walnut have 

 several above each other, the upper one being 

 the largest and at quite a distance from the 

 true axil. In these cases the uppermost is apt 

 to grow, and then the branch is said to be extra- 

 axillary. In the Sycamore the bud does not 

 show while the leaf remains on the tree, as it is 

 in the hollow of the leafstalk. In the winter 

 the bud has a ring-like scar entirely around 

 it, instead of the moon-shaped scar below as 

 in most trees. The Common Locust has several 

 Fig.u. buds under the leafstalk and one above it in 



