Moisture Release Characteristics of Forested Sand Entisols In Northern Lower Michigan
1966
Zahner, Robert | Hedrich, David R.
Forest growth is better on Grayling fine sand than on Grayling medium sand. Moisture release curves were constructed for samples from these two types and for pure sand fractions separated from the samples. Examples of the fine sand soil retained 10% and the medium sand soil retained 7% water by weight at field capacity (.06 atm tension), while both soils retained equal amounts, 2.5%, of water at 15 atm tension. Of the pure sand fractions, very fine sand retained substantially more water at low tensions than did the larger fractions amounting to more than five times the amount of readily available water. The fine sand soil type contained six times the amount of very fine sand fraction than did the medium sand soil type, 12% vs. 2% by weight. Thus, much of the difference in water retention between the two examples is attributed to the very fine sand fraction, probably also accounting for much of the difference in tree growth.
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