EXERCISE 33 

 THE OPENING OF A BUD 



Materials. Trees and shrubs in the field. During the winter, buds 

 may be caused to open by standing cut branches in water, but the 

 buds do not usually develop completely. 



Directions for work. In spring, at the time when buds are 

 about to open, select a conveniently located tree, or several of 

 them, with large buds. Observe the buds each day and make 

 written notes of changes observed, examining the same buds 

 each time. Continue until the shoots are several inches long. 

 A very interesting and valuable record may be secured by photo- 

 graphing the selected buds daily. The camera should be close 

 to the buds in order to secure a large image. 



What is the history and the final fate of the scales ? When 

 the bud is fully opened, is there left on the twig any mark 

 which shows the former position of the scales ? Do the scales 

 on any of the trees examined become more leaflike during the 

 period of observation ? 



What is the history of the growing shoot during the period 

 of observation ? How many inches, or what fraction of an inch, 

 per day does it lengthen when growing most rapidly ? Does 

 the number of new leaves increase during this period of rapid 

 growth, or have all the leaves been formed by the time the 

 shoot emerges from the bud ? In what way does the new shoot 

 differ from older shoots on the same tree ? Are there living 

 leaves on the older parts of the stem at this time ? 



Enter your daily observations, with dates, in your notebook, 

 and write a careful summary of the important facts connected 

 with the opening of a bud. 



References 



BERGEN and CALDWELL. Practical Botany, chap. vi. 

 BERGEN and CALDWELL. Introduction to Botany, chap. vii. 



[39] 



