146 THE CONNECTICUT POMOLOGICAL SOCIETY. 



it is not available to the apple trees. The trees are starving 

 in a land of plenty. 



2nd. The sod-mulch does not conserve moisture. The 

 chief study in the Auchter orchard for the summer of 1907 

 was that of the water content of the soil in the two plats. One 

 hundred samples of soil were taken at different times during 

 the summer and under conditions safe-guarded in every way 

 possible, to determine accurately the amount of moisture in 

 the soil. The anal\scs showed, approximately, that the water 

 content in the tilled soil during the past summer was twice 

 as great as in the sod plat, thereby substantiating what has 

 long been claimed, that tillage is a better means of conserving 

 moisture than mulching. 



The difference in the moisture conditions of the two soils 

 is enough to account for the differences in crops and trees 

 in the two plats. Trees must have water. If an apple tree 

 bears ten barrels of fruit, there are about 83/2 barrels of water 

 in the tree's output. In a full-grown apple tree, it is esti- 

 mated that the total leaf area is about 1,000,000 square inches. 

 Mr. F. C. Stewart of our Station has counted the stomata, or 

 pores, on a square inch of the apple leaf, and finds that a fair 

 average is about 130,000 per square inch; or, for the leaf area 

 of the whole tree, 150,000.000,000 pores. Now to supply the 

 demands of its ten barrels of apple children while these 150,- 

 000.000.000 pores are constantly giving moisture, is enough 

 to drive a tree to drink, and the apple tree becomes a hard 

 drinker. When, in the heat and drought of summer, the 

 apple tree is compelled to share its scant supply of water with 

 the thirstv horde of hangers-on found in an orchard sod, the 

 trees must suft'er. Still further, a diminished water supply 

 entails a cutting off of the food supply. Plant-food enters 

 the tree as a solution, and an apple tree suffering .from lack 

 of water, as a necessar\- consequence, suff'ers from a lack of 

 food. A thirsty plant is a hungry plant. 



3d. The sod-mulch soil is less well aerated. In the 

 experiments we are carrying on, I have not attempted to 

 secure evidence on this point. It is obvious that sod inter- 

 feres with the air supply in the ground beneath it, and it is 



