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the leaf area. iMeasuremeiits of leaf area were not made but the 

 merest glance through the orchard would show that there were more 

 and larger leaves on the tilled plot than on the sod-mulch plot. The 

 experienced orchardist knows that sparsity of foliage and smallness 

 of leaf can indicate but one thing, ill-health. 



So, too, there was something amiss with the color of the leaves. 

 It did not need a trained eye to detect the difference in color of fol- 

 iage in the two plots. The dark and rich green of the tilled trees 

 could be noted a half mile from the orchard indicating an abundance 

 of food and moisture and the heyday of health, while from the same 

 distance it could be seen that the foliage of the sod-mulch trees was 

 pale and sickly. Of all the signs of superiority of the tilled trees 

 the color of the foliage spoke most eloquently and more than one 

 man of the hundreds who visiied the orchard was heard to say 

 as his eyes lighted on the contrasting colors of the sick and of the 

 well trees "that satisfies me." The absence in color in the leaves of 

 the sod-mulch trees was due to a lack of chlorophyl or leaf-green. 

 Chlorophyl is essential to the assimilation of plant-food and when 

 it is lacking the trees become starved and stunted. The leaves on 

 the sod-mulch trees assumed their autumnal tints a week or ten days 

 earlier than those on the tilled trees and the foliage dropped that 

 much earlier, thus seriously cutting short the growing season of 

 the grassed trees and thereby impairing their future vitality. 



The new wood produced by the grassed trees tells a similar tale 

 of injury. It was not half that produced on the tilled trees ; the 

 twigs were not plump and well filled out; there were fewer new 

 shoots ; and the wood of the mulched trees lacked the clear, bright, 

 rich brownish tint of health so that in mid-winter one could pick 

 out mulched trees and tilled trees by the color of the wood. 



As to color there is no question but that the fruit from the sod- 

 mulch plot is much more highly colored than that from the tilled 

 plot. This difference varies with the season. ]\Iulched fruit ripens 

 from a week to two weeks earlier than tilled fruit. If the variety 

 and the season are such that the tilled fruit can remain on the trees 

 some days after the mulched fruit must be picked the difference in 

 color is much less. The lighter color of the tilled fruit is readily 

 and clearly explained. The coloring matter in the skin of the apple 

 like that in the leaves, consists of chlorophyl or leaf-green. The 

 coloring of ripening fruit is due to the changing of the chlorophyl 

 of the skin into the colored substances of autumnal tints. There- 

 fore since the sod fruit ripens earlier it colors earlier and in most 

 seasons better. 



The abnormally high color of the sod fruit in this orchard is 

 one of the most marked signs of the deleterious eff'ect of the sod 

 on the trees. Every man of experience has observed that when a 

 tree is starved, stunted, girdled, or injured, its foliage and its fruit 

 take on high color. Radiant color in fruit or leaf is often the hectic 

 flush of a diseased patient. The bright color of the fruit of the sod- 

 mulched trees may be purchased at the expense of the vigor and the 

 health of the tree. 



