Moisture of the Soil. 493 



cation at the siuface we must look for it below. The binding 

 property of lime is well known from its use in the trades. In 

 its passage down through the particles of sand, it does not pro- 

 ceed far before it probably begins to bind the grains together, and 

 there is formed a layer somewhat impervious to water (Fig. 147). 



Frequent and small applications of lime have been found most 

 beneficial. From twenty to forty bushels per acre will usually 

 be found to give the best results. On marshy and boggy lands 

 which have recently been drained, but still remain sour and full 

 of undecomposed organic matter, the benefit derived from apply- 

 ing lime is very great. It breaks down the vegetable matter, 

 neutralizes the acid and makes plant food available. In this 

 case, its action upon the plant food in the soil is more important 

 than its agency in the conservation of moisture. 



Windbreaks to save moisture. — The drying effects of the wind 

 are well know^n, when it has unbroken sweep over a farm. The 

 loss of moisture from this cause is very great. Windbreaks are 

 not only a protection in winter, but they serve equally w^ell in 

 summer to protect the fields. The hedge-row around a field is 

 not, then, entirely useless, since it serves its purpose as a con- 

 server of moisture. (See our Bulletin IX.) 



Selection and management of crops in relation to soil moisture. — 

 Crops should, as far as possible, be adapted to the conditions 

 best calculated to furnish them with a sufficient supply of mois- 

 ture. The grasses and grains thrive best on loamy or clay soils 

 w^here the moisture is held and not allowed to pass away by per- 

 colation. On sandy and gravelly soil crops should be grown to 

 which frequent culture can be given, for in this way we may aid 

 in bringing water to the reach of plants. On sandy soils so 

 treated, some catch crop should be grown which can be plowed 

 under for green manure, thus serving to keep up the humus of 

 the soil. The practice of growing crops, especially grains and 

 grasses, in an orchard, cannot be too strongly condemned. (See 

 Bulletin 102.) The soil should be left bare in early summer, not 

 only that we may harrow and cultivate and thus conserve 

 moisture and set free plant food, but because the loss of mois- 

 ture from the growing grain crop is so great as to deprive the 

 fruit trees of the amount necessary for their use. Crop an or- 



