[Chap. XXVI FORMS AND EXTERNAL FEATURES OF STEMS 261 



terminal and lateral buds. Dormancy during summer and autumn is com- 

 mon in buds of most trees and shrubs in temperate climates. The period 

 of this type of dormancy may often be shortened by artificial changes 

 in temperature and by the application of certain chemical compounds. 

 Numerous buds on each plant are kept dormant by apical dominance. 



