New YorkK AGRICULTURAL EXPERIMENT STATION. 489 
which investigations with peaches grown in pots with several 
other plants show that the peach does not thrive if its roots are 
in close proximity to those of certain other plants. 
As has been described on page 468 apple roots escape at every 
opportunity from the grass roots, establishing, where nearby 
tilled or sodless soil permits, a veritable “ dead line” between 
apples and grass. The extremely deleterious effect of the grass 
roots on the apple, and the extreme sensitiveness of the apple 
roots to grass roots, curving away from them as if they had 
perceptive organs, suggests that there may be an unknown fac- 
tor partly responsible for the effects of grass on apples. In 
this respect, however, this experiment is not crucial and it is 
best for the present to attribute the injurious action of the 
grass in the main to known factors — to disturbances of plant 
nutrition, leaving the more obscure factor until further evi- 
dence is secured. 
APPLICATION OF RESULTS. 
The well being of nearly all the plants which minister to the 
needs of man is improved by tillage. It does not appear from 
this experiment that the apple is an exception. This fruit re- 
sponds to high cultivation in the nursery row; it seems to con- 
tinue to do so when transplanted to the orchard. Results as 
positive as in this experiment can be made very comprehensive. 
They will, it is believed, apply to all varieties of apples, and 
to all fruits, for that matter, and to practically all fruit soils 
and conditions. It should not be expected, however, that sod 
will be deleterious in the same degree under all conditions. It 
should be expected, for instance, that in a deep soil, where the 
apple roots can escape from the grass roots, or in one contain- 
ing a great amount of soil moisture, the harmful effects of the 
grass will not be so marked as otherwise. The experiment 
does not show that apples can not be grown in sod. There are 
many orchards in New York which would prove the contrary. 
It suggests, however, that apples thrive in sod, not because 
of the sod, but in spite of it. The fact that there are many 
