208 The Principles of Fruit-growing. 
crops, as grain and grass, for specific plant-food ele- 
ments, cannot be applied with any degree of accuracy 
to fruit crops, particularly the larger fruits, as pears, 
apples, peaches, grapes, and plums, because these dif- 
fer from the cereals, grasses, and vegetables, first, in 
their habits of growth, second, in the character of 
the produce, and third, in their relation to soil ex- 
haustion. 
“Tn the first place, farm crops, as a rule, require 
but one year for the entire processes of vegetation 
and maturation. For fruit crops, with but few ex- 
ceptions, the purely vegetative processes continue for 
at least three years, and with many kinds much 
longer, while after the fruit-bearing period begins the 
vegetative processes do not cease, but are coincident 
with the growth and ripening of the fruit. In the 
second place, the product of the harvest, namely, the 
fruit, differs very materially in its character from 
that of ordinary farm crops, which mature their fruit 
and die in one season, because a whole season is re- 
quired for its growth and development; that is, it is 
necessary that there shall be a constant transfer of 
the nutritive juices from the tree to the fruit 
throughout the entire growing season, while the 
growth for each sueceeding year of both tree and 
fruit is dependent upon the nutrition acquired and 
stored up in buds and branches, as well as upon that 
which may be derived directly from the soil. In the 
third place, the relation of fruit-growing to soil ex- 
haustion is very different from that in general-crop 
farming, because in orchards there is an annual de- 
