48 FIELD OPERATIONS OF THE BUREAU OF SOILS, 1918. 



WapelJo, the county seat, and Columbus Junction, Morning Sun, 

 Letts, Oakville, and Grandview. Produce is sliij^ped from these 

 points to Chicago, St. Louis, and Boston. 



The climate is temperate and healthful. The mean annual precip- 

 itation is 34.07 inches. The average annual snowfall amounts to 

 26.8 inches. The average growing season lasts from April 24 to 

 October 16, or 175 days, and is ample for maturing all the crops com- 

 monly grown. 



In the early days wheat, corn, oats, and flax were the principal 

 crops grown, and little live stock was kept. At the present time 

 live-stock farming predominates. The principal crops are corn, oats, 

 hay, winter wheat, rye, potatoes, sweet corn, and barley. Cattle, 

 hogs, horses, and sheep are raised in large numbers. 



The sandy soils of the county are recognized as best adapted for 

 rye, melons, sweet potatoes, and truck crops; the light-colored bluff 

 soils for wheat ; and the dark-colored soils for corn and oats. 



The farms are well equipped with up-to-date machinery. Most of 

 the farmers practice a rotation, the most common one consistmg of 

 corn, corn, oats and clover (or wheat and clover), and clover. Prac- 

 tically no fertilizer except barnyard manure is used. 



The size of farms ranges from 40 to 1,600 acres, averaging 153.6 

 acres in 1910. Sixty-four per cent of the farms are operated by 

 owners, 35.2 per cent by tenants, and 0.4 per cent by managers. 

 Almost all the farms operated by tenants are rented on the share 

 system. 



Approximately 60 per cent of the county is upland, 20 per cent 

 terrace, and 20 per cent first bottom. The loessial upland soils are 

 classed in six series, the Grundy, Muscatine, Clinton, Tama, Knox, 

 and Putnam. Only one glacial soil, the Lindley silt loam, occurs in 

 this county. 



The terrace soils are derived from old alluvial material and may 

 have been capped with a thin layer of loess. Ten terrace types are 

 mapped, correlated in the Bremer, Buckner, Waukesha, and Calhoun 

 series. 



The first-bottom soils are derived from recently deposited allu- 

 vium. Nine types, classed m the Wabash and Cass series, and the 

 undifferentiated types of Muck and Riverwash, are mapped. 



The Grundy and Muscatine are quite similar prairie soils, having 

 dark-colored surface soils and mottled subsoils. They are preemi- 

 nently suited to corn, but are well adapted to oats and hay, and give 

 good yields of other general farm crops. The Grundy occurs on the 

 western upland, the Muscatine on the eastern. 



The Clmton silt loam is a fairly extensive type occurring on both 

 uplands, generally near the bluffs and the major drainage ways 

 where the topography is rather rough. In its natural state the type 



