44 EARTHS AND SOILS. 



earth ; — by frequent returns of grass crops ; — by repeated 

 applications of manure ; — and by irrigation, if the water 

 be full of sediment, and judiciously applied on a proper 

 form of surface." — Code of ^.Agriculture. 



Gravelly soils, like sandy ones, if dry, become soon 

 heated by solar influence, but they retain the heat longer 

 than sands. They are therefore the earliest soils, and 

 are most liable to suffer from the droughts of summer. 

 Hence the crops upon them should be upon a clover or 

 grass ley as often as practicable. 



The crops suited to these soils, are Indian corn, tur- 

 nips, clover, barley, rye, peas, oats, and, if a portion of 

 the ground is calcareous, good crops of wheat may be 

 obtained. When they are cropped with small grains or 

 summer-ripening crops, these crops should be sown very 

 early. The w^armth of the soil will admit of it, and the 

 crops may then mature before they are injured by the in- 

 tense heats of our mid-summers. If gravelly lands are 

 poor, or unfriendly to arable husbandry, they should be 

 left in wood, or planted in wood. 



3. Clay soils are tenacious, stiff, very retentive of 

 moisture, can only be well worked in favorable seasons, 

 and require extra labor in their tillage. If too dry, the 

 soil breaks up by the plough in hard clods or lumps. If 

 wet, it assumes the appearance of mortar. In either 

 case, pulverization, the main object of ploughing, is not 

 effected. Yet clay soils yield heavy crops, when they 

 are got in in good order. The great expense of tillage, 

 however, and the rich herbage which they afford, induce 

 many farmers to appropriate them mainly to meadow and 

 pasture. 



But clay soils vary greatly in texture, according to the 

 quantity of other earths which are commingled in their 

 composition ; and they vary in fertility according to the 

 quantity of vegetable matter which they contain, and the 

 nature of the subsoil upon which they repose : if the lat- 

 ter is retentive, and impervious to water, the soil will be 

 wet, cold, and unfriendly to those crops which require 

 much heat to bring them to maturity. Clay soils are of 

 all intermediate qualities between a dead barren mass and 



