Abstract:
FIELD STATIONS WERE ESTABLISHED TO STUDY THE MOISTURE CONTENT OF OHIO'S SOILS. DIFFERENT SOILS OR DIFFERENT LOCATIONS SHOWED VERY MARKED DIFFERENCES IN WATER CONTENT ON THE SAME DAY. THE QUANTITY OF CLAY IN THE SOIL SEEMED TO HAVE NO AFFECT WHATEVER UPON THE AVERAGE WATER CONTENT. THE SURFACE OF THE SOILS TESTED CHANGED THEIR MOISTURE QUICKLY FROM 2 PERCENT TO 124 PERCENT OF THEIR DRY WEIGHT DUE TO RAIN, SNOW, THAWING AND DRYING WEATHER. SUBSOILS BELOW SIX INCHES IN DEPTH CHANGE COMPARATIVELY SLOWLY IN WATER CONTENT AND OVER VERY NARROW MARGINS. SO THE DRY PORTION OF THE SUMMER OR FALL THE WATER CONTENT OF THE SUBSOIL MAY RUN FROM 60 TO 65 PERCENT OF THE WATER CONTENT DURING THE WINTER AND SPRING. CERTAIN SOILS SHOW NEARLY DOUBLE THE MOISTURE CONTENT AT ALL TIMES THAN DO OTHER SOILS. WET AND DRY YEARS MAY MAKE 30 TO 50 PERCENT DIFFERENCE IN THE AMOUNT OF WATER WHICH THE AMOUNT OF SOIL MAY HOLD. FLUCTUATIONS OCCUR IN THE WATER CONTENT OF SUBGRADE SOILS WHICH IT IS IMPOSSIBLE TO TRACE DIRECTLY TO RAINFALL, EVAPORTATION, OR OTHER SURFACE WEATHER CONDITIONS. WHEN THE BEARING VALUE OF THE VARIOUS TYPES OF SOIL WAS DETERMINED, THESE DATA OF MOISTURE CONTENT THROUGHOUT THE YEAR UNDER DIFFERENT CONDITIONS MAY BE OF GREAT VALUE. MOISTURE CONTENT IN HEAVY CLAY SOILS AT DEPTHS OF SIX INCHES TO TWO FEET WAS NOT LARGELY AFFECTED BY LONG OR HEAVY RAINS BUT IS INCREASED BY SNOW BLANKET. AVERAGE ANNUAL MOISTURE AT THESE DEPTHS IS SLIGHTLY LESS THAN MOISTURE EQUIVALENT.
Supplemental Notes:
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