30 
The: Colorado Experiment Station 
Diagram 4.—Percentage of Principal Varieties of Apples for Each District and for Val¬ 
ley as a Whole (Adapted from Table IV). 
Cultural Methods 
As a general thing, apple orchards are cover cropped. Alfalfa 
and clover are mostly used for this purpose. Where properly 
treated, this is undoubtedly beneficial to the trees, since it adds 
fertility and humus to the soil and keeps the soil in better condi¬ 
tion than when cultivated. Clover is the more desirable of the 
two, since it is easier to eradicate. 
Many growers in 1915 took a fair yield of hay from their or¬ 
chard cover crops. Ordinarily, this practice is to be condemned, 
but in most cases since there was no fruit crop, it did not injure 
the trees noticeably. 
Pruning 
* 
In order to produce apples of good size and color, regular 
pruning is essential. This must be done systematically and intel¬ 
ligently, but fearlessly. The object should be to thin out surplus 
wood growth, keeping the trees open to light and air, and to in¬ 
duce a low-spreading form of tree rather than a high and narrow 
one. A considerable amount of thinning may be eliminated by 
proper pruning. 
Few orchardists have paid enough attention to pruning. The 
failure has been not to prune regularly or properly, and often both 
are wanting. Many trees are headed and pruned high, so that a 
very long ladder is necessary for picking. Most of the younger 
orchards, however, are better pruned. 
