82 PLANT LIFE ON THE FARM. 
Bud Formation. —In the higher perennial plants, 
among which are included many which come under the 
notice of the farmer, asexual multiplication is effected by 
means of buds. When a bud is to be formed, growth in 
length is checked, the stem or the branch ceases length- 
ening, the outer leaves often become reduced to a scale- 
like condition, while the inner, central, and younger 
ones remain in an undeveloped state until the warmth of 
spring calis them into growth, when they gradually 
lengthen into shoots, as in fruit and timber trees. While 
the buds remain fixed to the trees which gave them 
origin, their growth and development is a process of ex- 
tention or branching merely. Similarly the process of 
“tillering ” is simply due to the formation and develop- 
ment of buds and shoots from the nodes or knots at the 
base of the stem of the wheat, and is to be regarded as a 
process of branching rather than of actual multiplication. 
Such branches are formed more readily in proportion as 
the seed is not buried deeply. The same process of 
growth which is desirable in a cereal or in clover is 
highly objectionable in the case of ‘‘ weeds,” such as 
docks, thistles, and plantains. The imperfect measures 
often taken to exterminate these often tend to increase 
the mischief by bringing about the formation of many 
new buds. hen buds become detached naturally, or 
are severed from the parent artificially and made to grow 
—as when a gardener takes a “slip,” ‘‘ buds” a rose, or 
“‘ grafts” a fruit tree—the process is really one of multi- 
plication. So, when a farmer plants a ‘seed potato,” 
which yields him, it may be, forty-fold, he really plants, 
not a “seed,” nor a root, but a peculiar form of bud 
called a tuber. 
Tubers,—A potato, in fact, is an underground branch, 
or connected series of buds, forming a swollen subter- 
ranean shoot, In this are stored up the starch and other 
