544 Report of the Department of Horticulture 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." 



Any one with experience would pick the tilled trees as the healthier 

 from the condition of the new wood. 



As the experiment has progressed the dead wood in the sodded 

 trees, noted in the first report, has increased out of all proportion 

 to expectations from the first few years' work. This dead wood, in 

 the quantities present, was so certain a sign of failing vigor and 

 decrepitude that the owner at the close of the ten-year period feared 

 for the life of his trees if they were to be kept in sod. The decrepit 

 and moribund condition of sodded orchards in New York, even 

 when mulched, as indicated by dead wood, has done much to drive 

 sod mulching out of practice in commercial orchards in this State. 



FOLIAGE. 



The importance of good foliage. — In the most literal sense " light 

 is life " for plants. Foliage absorbs energy from the sun's rays and, 

 as every school-boy knows, plants have a marvelous faculty of 

 developing and placing their leaves so that the largest possible 

 amount of sunlight will be absorbed. Under the influence of the 

 sun's rays the carbonic acid of the air and the soil solution are 

 synthesized into the organic materials from which the plant tissues 

 are constructed. The foliage, then, is the assimilating apparatus 

 of the apple-tree. In a slightly different sense it may be said to be 

 the breathing apparatus of the tree. Or, in another way a leaf is 

 well called a solar engine getting its energy from the light rather than 

 from the heat of the sun. In any and all of these aspects of the 

 functions of foliage it is seen at once that the efficiency of an apple- 

 tree depends in large measure upon its foliage. What is the effect 

 of these two methods of treatment upon the foliage of the trees in 

 this experiment? 



Color of foliage. — The part of the leaf which acquires energy from 

 light is the chlorophyll, the green coloring matter, found in the 

 leaves of all higher plants. Now the amount of this indispensable 

 chlorophyll in the leaf of an apple is measured by the depth and 

 richness of the green of the foliage. Leaf-color is the readiest and 

 most delicate gage the fruit-grower can use in determining the well- 



