466 Report OF THE HORTICULTURAL DEPARTMENT OF THE 
Still another indication of the superiority of the wood for 
five years from the tilled trees is found in the greater weight 
of the wood from the tilled trees. When the 240 branches 
from each plat had been. measured for annual growths the 
weights of the wood were taken. It was found to be 7.2 
pounds for the sod and 21.3 pounds for the tilled trees—strong 
testimony to the greater health of the tilled trees. 
Color of new wood.—During the dormant season there is a 
striking difference in the color of the new wood of the trees 
on the two plats. The whole tree top on the tilled land is a 
light, bright, glossy olive-green color, emphasized somewhat by 
the plumpness of the twigs and the tautness of the bark. The 
tree tops on the sod-mulch plat were darker, of a brownish 
cast and less glossy and bright, giving a prevailing color that 
distinguished the sod-mulch plat from the tilled plat a mile 
away. One cannot well describe the color of wood on healthy 
trees and that on trees which lack vigor but the practiced eye 
of the nurseryman or fruit grower discerns a difference at a 
glance. Only a look was needed at the trees in these two plats, 
- with or without foliage, to be convinced that the tilled trees 
were in the very perfection of health and that there was some- 
thing amiss with the sod-mulch trees. 
Dead wood.—In trees as old as these in this experiment 
there is always some dead wood, usually on lower branches, 
though now and then a limb succumbs seemingly without cause 
in any part of the tree top. It is a sign of failing vigor and 
decrepitude if there is much of this dead wood. As this ex- 
periment has progressed the amount of dead wood in the sod- 
mulch plat has increased until at the end of the fifth year 
there is scarcely a tree without a showing of dead branches. 
In no ease is there enough to cause fear for the life of the tree, 
but in many trees the number of small branches, dead or dying, 
makes it certain that the trees are seriously out of health. 
The root system.—Of all the organs of the tree the roots 
bore strongest testimony to the deleterious effects of the grass 
in the sod orchard. This is as might be expected; for the roots 
are possibly the most sensitive of plant structures, responding to 
