I 
f 
20 The Colorado Experiment Station. 
learns what a tree properly thinned should look like. With these trees as a 
model it is surprising how close one can come to leaving just the right num¬ 
ber. I think it is possible, by careful work, to come within a box of the 
ideal. But knowing how much the tree should produce is where the experi¬ 
ence counts. Not many varieties of apples will require much thinning be¬ 
fore they are ten years old, and at this age the average 'tree should produce 
about eight boxes of fancy fruit; some will produce more and some less. 
After the tenth year a gain of a box per year would be a conservative es¬ 
timate. Of course, the yield will vary under different conditions; and, while 
this is not a rule that can be implictly followed, it is surely more accurate 
than thinning to a certain. distance. The thinner first removes defective 
or wormy specimens, and he should be supplied with a bag to carry the 
wormy ones from the orchard to be destroyed; then those from the tips of 
the limbs may as well be removed, for they seldom make fancy fruit; and, 
if possible to do it and leave the required amount, thin to one fruit on the 
spur. June and early July is the proper season for thinning apples and pears. 
Experiments have shown that it pays to thin apples. The fruit is improved in 
both size and color; the trees bear more regularly, and trees that may break 
under heavy loads are saved. Some say it is expensive to thin; but, if one stops 
to think, it really costs no more to pick fruit in June than it does in October. 
, A man can thin from ten to fifteen twelve-year-old trees per day, and the 
actual cost of thinning should not add to exceed two cents per box to the 
cost of production. It is true that the results the first season are often dis¬ 
appointing, for an unthinned tree may produce sixteen boxes of fruit that 
will grade 50 per cent, fancy, while the thinned tree of the same age only 
produces ten boxes that will grade 95 per cent, fancy. It hardly seems 
profitable, but the next year will tell, and it is safe to say that two years 
running the thinned tree will produce as much fancy as the unthinned tree 
will produce of both fancy and choice. 
Thinning Pears.—Methods of thinning pears differ little from methods 
of thinning apples; the principles are the same. As a rule, the pear tree 
will produce about as many boxes of pears as will the apple tree of the same 
age produce boxes of apples. The fruit is generally picked on the install¬ 
ment plan, and it is possible to mature a large crop of fancy fruit; and 
fruit that is small may be left until it reaches the decided size. Pears run¬ 
ning from 135 to 150 to the box are considered ideal size, and pears for 
such a pack must measure from two and one-fourth to two and three- 
fourths inches in diameter. Pears larger than three inches are really not 
as desirable for the fancy fruit trade as those of smaller size. The fruit 
stands like a pear that can be sold at a profit, two for five cents, and there 
is no profit to be made in selling the larger ones for that price, and they 
are not large enough to sell for five cents each. 
Thinning Peaches.—In growing peaches much of the thinning is done 
with the pruning shears during the pruning season, but additional hand¬ 
thinning is absolutely necessary. A good grade of peaches should run less 
than 90 to the box, and we may say it seldom pays to ship smaller fruit. A 
size that will pack less than 80 to the box is desirable. The young peach or¬ 
chard that has been properly pruned will do well to average a box of fruit 
to the tree during its fourth season’s growth, and the yield should increase 
at the rate of about two boxes per tree per year. Unless the trees have been 
exceptionally well pruned and cared for, they will rarely more than hold 
their own after the eleventh or twelfth year. The one object of thinning, 
as practiced with the stone fruits, is to produce better fruit. The thinning 
should be done before the foliage gets too heavy and before the pits begin 
to harden. By carefully thinning a few trees and estimating the number of 
fruits left, one can soon form an ideal to work by. The pruning shears may 
be used as a help in thinning, and fruiting wood not necessarily needed may 
be removed entirely. 
