WINTER BUDS 329 



cold winter or a dry season), and the shoots of a woody 

 perennial must be protected from drying up during 

 that period, and this is effected by another secondaiy 

 meristem, the cork-cambium. 



The main structural features in which a woody 

 perennial differs from a herbaceous plant are therefore 

 three. First, it produces secondary vascular and 

 supporting tissue. Secondly, it has means of protection 

 (bark) of its general shoot surface during the unfavour- 

 able season. Thirdly, its aerial buds (winter buds) 

 are protected during the same period. 



Winter Buds. At the tips and on the sides of the 

 younger portions of the branches of a tree or shrub 

 buds are to be seen during the winter covered with 

 brown scales. These bud scales are modified leaves 

 which were formed at the end of the last growing season, 

 and they completely cover in the delicate tissue (apical 

 meristem) in the interior of the bud. The winter bud 

 scales are largely composed of cells with corky (water- 

 proof) walls, and other (gland) cells are often present 

 which secrete a resin or gum that glues the scales 

 together and thus renders the bud additionally water- 

 tight. This arrangement not only prevents the tissues 

 within from drying up, but also stops rain from soaking 

 in and rotting the tissues. 



Within the bud are young, partly developed foliage 

 leaves, and sometimes, in addition, a group of ready 

 formed flower buds (inflorescence). 1 In the case of 

 fruit trees, such as the apple and pear, those winter buds 

 which contain the young flowers are called fruit buds, 

 because, of course, it is the potential production of fruit 

 from the flowers which interests the fruit gardener. 



1 Compare the buds on the crocus corm and in the tulip bulb, which 

 are also winter buds, though borne on an underground shoot. 



