THE DRAINAGE OF FARM SOILS 193 



unmanageable when dry, and sticky when wet. 

 They are not what would be called wet soils, 

 neither are they shallow, but they are not mellow 

 and they run to extremes, either very dry or very 

 wet. It is impossible to work them early in spring. 

 Heavy rains put them in such a condition that 

 they cannot be cultivated for several days after the 

 crops begin to need tilling. The surface bakes 

 and cracks. Such soils are improved by plowing 

 under a green-manuring crop, by under-drainage, 

 or by both. In many cases the addition of humus 

 is sufficient to bring the soil into good heart; in 

 extreme cases under-drainage must be called to the 

 aid of humus. 



Land drainage is not chiefly concerned, as many 

 suppose, with carrying off surplus water from very 

 wet soils. Drainage adds far more to the value 

 of farm soils, and to the profits in cropping them, 

 by improving soils that are shallow, or in bad tex- 

 ture, or but slightly wet, than by removing excess 

 water from very wet soils. Many thousands of 

 acres of swamps, meadows and marshes have been 

 brought under profitable husbandry by drainage; 

 but me combined area of these is very small com- ^ 

 pared with the hundreds of thousands of acres of 

 farm lands that are not excessively wet, but that . 

 have been greatly improved by the same means. ^ 

 Drainage, and especially under-drainage, is of 

 greatest service upon land already under cul- 

 tivation, but which is not yielding maximum crops 

 because of inequalities in the water supply. Far- 

 mers should make a critical examination of 

 each field in this respect, regardless of the 

 length of time that it has been cultivated. 

 Deficiencies may exist that never have been 

 suspected. 



