OBSERVATIONS ON SOIL MOISTURE. 181 



marked wlien the six-inch samples are considered alone. The influ- 

 ence of cultivation was felt, however, quite strongly even at the depth 

 of twenty inches. 



GARDEN SOIL — CULTIVATED, UNCULTIVATED, MULCHED — IN GRASS. 



In order to get more uniform conditions than could be had in the 

 orchard, three small plots were laid out in the gardeu. The garden 

 was plowed to a medium depth early in the spring. On June 6 a 

 mulch of coarse horse manure was spread on one plot. The mulch 

 was three inches thick after having settled for two months. Another 

 plot was cultivated about tiiree inches deep, on an average once in two 

 weeks during the summer. A third plot was left uncultivated. The 

 weeds wCTe cut off at the surface of the ground with a sharp hoe as 

 soon as they appeared. The three plots together covered a space about 

 three rods long by two rods wide. Adjoining these plots was the 

 head-land of the garden, a strip about one rod wide, covered with an 

 old, thick June grass sod. Next to this was a field of alfalfa two 

 years old. The land here was quite level. This, together with the 

 small size of the plots, rendered the conditions of the five plots quite 

 uniform. 



Determinations of the soil-moisture of these plots was made June 

 15, June 25, July 27, and September 6. Two sets (six samples) gave 

 the average per cent of moisture for each plot at each date. The re- 

 sults are shown by the curves (Fig. 3). It will be seen that the 

 mulched plot gave the highest and most uniform per cent of water. 

 The cultivated plot came next, and the uncultivated third. The al- 

 falfa and June grass gave very much lower per cents of moisture. 

 On June 15 and June 25, the samples twenty inches deep gave almost 

 no difference in per cent of water between the plots cultivated, uncul- 

 tivated, and mulched. This was no doubt because the mulch had 

 been applied so recently. By July 27 the effect of the cultivation 

 and mulch was readily seen in the twenty-inch samples. 



POTATOES — MULCHED VS. CULTIVATED. 



A small plot of potatoes was mulched with three indies of straw at 

 the time of planting. Another plot was given shallow cultivation. 

 On June 25 the per cent of water in the cultivated plot was 19.6; in 

 the mulched plot, 21.6. 



