6 SOILS OF THE EASTERN UNITED STATES. 



grain crop to assist in the preservation of the humus content of the 

 surface soil. Such cropping systems have already been adopted in 

 all of the older settled communities and the effect has been to main- 

 tain or even to increase the naturally high-producing power of the 

 Carrington clay loam. This is notably the case in the dairying and 

 stock-raising regions of Iowa and Wisconsin, where stable manure 

 is carefully saved and applied to the ground as it is prepared for the 

 corn crop. Applications of 10 to 12 loads of stable manure to the 

 acre, once in five or six years, are adequate for its maintenance in an 

 excellent condition of fertility. 



The strong tendency to grow large areas of small grains has led 

 to the shallow plowing of this soil in certain areas. The depth of 

 plowing should be increased gradually from the present practice of 

 plowing 4 or 5 inches deep until an average depth of 8 or 9 inches is 

 attained. If the plowing is done in the fall and the ground is allowed 

 to compact during the winter months, good results will follow. 

 Spring plowing should usually be to a less depth and it is usually 

 desirable to roll the ground in addition to the customary fitting with 

 the plow and harrow. In all cases every effort should be made to 

 secure a well fined and compacted seed bed. 



LIMITATIONS UPON SPECIAL CROPS. 



In southern Wisconsin, near to special city markets, considerable 

 areas of the Carrington clay loam have come to be devoted to the pro- 

 duction of cabbage as a late truck crop. The areas of the type best 

 suited to this special crop are those lying at the lower altitudes and 

 originally marked by somewhat deficient drainage and consequent 

 accumulation of excessive amounts of organic matter in the surface 

 soil. These areas, somewhat more mucky and moist than the general 

 average of the type, are well suited to the growing of cabbage, onions, 

 and even celery, where the local market permits of these special 

 crops. The Danish Baldhead is the variety of cabbage chiefly grown 

 for shipment to the city markets, while other varieties are grown for 

 local use and for manufacture into sauerkraut. Yields of 12 to 15 

 tons per acre are secured and increasing acreages of this crop are 

 being annually planted. Good artificial drainage of portions of the 

 type rather more mucky than the average is necessary for suc- 

 cess with this crop. The occasional liming of the land devoted to 

 cabbage production is also to be recommended. Rotation of crops 

 and fertilization with stable manures are even more essential than 

 when the soil is given over to grain and grass growing. 



Some of the more elevated and better drained areas of the Car- 

 rington clay loam have been used for the setting of home orchards 

 with good results. Hardy apples, pears, and cherries succeed when 

 thus planted, but the type can not be recommended as an orchard 

 soil for commercial development. 



