CHAPTER X 



BUDS; GROWTH OF STEMS; PRUNING; PROPA- 

 GATION BY STEMS 



Buds 



Nature of Buds. — Buds contain a partially developed portion 

 of a stem with leaves and also flowers, when present, in an em- 

 bryonic state. A close study of buds, like those of fruit trees, 

 shows that the stem portion contained is 

 very short and that the leaves and flowers, 

 although they may be seen with a micro- 

 scope of low power or often with the naked 

 eye, are very rudimentary. Buds are often 

 defined as undeveloped shoots. The most 

 important thing about a bud is that it con- 

 tains the meristematic tissues upon which 

 growth in length (primary growth) and the 

 formation of new leaves and flowers depend. 

 For this reason, when the bud on the end of 

 a branch is removed, the branch can grow no 

 more in length at that point. {Fig. 182.) 



Buds are common to all plants, but they 

 are most noticeable in perennials, such as 

 Hickory bud. a, furry trees which have dormant periods occurring 

 inner scales; h, outer during the winter season in temperate re- 

 scales; Z, folded leaf; m, gions or during dry seasons in warm coun- 

 apical meristem; r, re- ^^-^^^ rj.^^ ^^^^ ^^ ^j^^^^ ^^^^^ ^^^ ^^^^^ 

 gion to which the scales . , , , ^^ i -ii 



are attached. Modi- ^^ resting huds and are usually covered with 

 fied from Andrews. scales which protect the inner portions from 

 drying and other destructive agencies. The 

 scales overlap, forming a covering of more than one layer, and 

 are often made more protective by becoming hairy or waxy. Bud 

 scales are closely related to leaves and, in most cases, are simply 

 modified leaves. Sometimes, however, they are modified stipules 

 which are leaf appendages. 



204 



Fig. 182. — Lengtl 

 wise section through a 



