106 BOTANY 
for existence over others not possessing it in the same 
degree. Begonias are often propagated by buds pro- 
duced on their leaves. The leaf is sliced and fixed to 
the damp earth of the pot, when the edges of the cut 
produce buds and roots that give rise to new plants. 
In the poplar, as has been remarked, such buds may 
form suckers from the root. Some trees, like the 
walnut, produce accessory buds in the axils of their 
leaves. Usually only the chief or central bud matures, 
but, if anything happens to this, one of the accessory 
buds develops to take its place. This is nature’s pro- 
vision against loss through wind, frost, or other cause. 
The buds of many trees are, in winter, covered with 
leathery bud scales, and even in some eases with a 
eummy or resinous coat which protects the tender 
leaves and growing point against cold and drought; 
for, in winter, when the leaves have fallen, water does 
not pass freely from the soil. Such scales are found 
on the ash and other trees, while in the willow they 
are replaced by a dense growth of hairs. 
After the leaves have fallen in autumn, the buds 
remain dormant throughout the winter; but, when 
spring has come, the seales fall off, and, beginning at 
the base, the leaves unfold. At the same time the 
internodes lengthen, and, in the axil of each tender 
leaf, a new bud appears, in its turn to lie dormant 
through the winter, and develop in the spring. 
Before leaving this subject we must note that all 
buds do not develop into leafy shoots. Some are 
flower buds and produce, instead, flowers, which, after 
all, are themselves but branches clothed with groups 
of leaves that have been specially arranged and 
modified for reproduction. 
Budding and Grafting are horticultural operations 
by which, in one case, a bud, and in the other, a twig 
called the scion, taken from a plant it is desired te 
propagate, is fixed to and made to unite with a stock 
