60 FIELD OPERATIONS OP THE BUREAU OF SOILS, 1910. 



VINA CLAY LOAM. 



The soil of the Vina clay loam consists of a light-brown, very 

 smooth textured clay loam with a tendency' to puddle and crack 

 slightly over a considerable proportion of its area. This material may 

 extend to a depth of C) feet, but is typically underlain at depths below 

 24 inches by a slightly lighter colored clay loam or heavy loam, some- 

 times carrying small quantities of gritty material. At times a few 

 small waterworn, volcanic gravel occur in the surface soil, but never 

 in quantities sufficient to alter field conditions. Everything con- 

 sidered, both the soil and subsoil are remarkably fine in texture and 

 inclined to compact. These characteristics do not prevent the soil 

 from becoming quite friable with proper tillage. At a minimum 

 depth of about 5 feet, usually much more, is found the volcanic con- 

 glomerate underlying the Tuscan series. It can scarcely in any 

 instance seriously affect the agricultural value of the type. 



This type is rather an important one, occurring in several extensive 

 bodies on the east side of the Sacramento River. It usually occurs as 

 rather broad tracts just below the marked terrace separating the 

 upland Tuscan series from the alluvial valley of the Sacramento. It 

 lies at a general elevation only slightly above the soils classified with 

 the Sacramento series. Along the contact with the Tuscan series 

 distinct lines of division appear, but in separating it from other tj^pes 

 the boundaries were more or less arbitrarily drawn. 



The Vina clay loam typically has a level surface marked by shallow 

 depressions and abandoned waterwa3's. The type is subject to inter- 

 mittent ovei'flow by flood waters of the small streams as they emerge 

 from their small canyons into this plains region. The surface drain- 

 age is sluggish. 



The t3'pe is entirely alluvial in origin, being the finer material laid 

 down in quiet water by the lateral drainage ways along the sides of 

 the great alluvial plain. The material is derived largely from the 

 Tuscan series of soils. 



In a natural state the Vina clay loam supports valley oaks of large 

 size. Luxuriant gi'owths of wild oats yield hay upon such portions 

 as are not under cultivation. Grain growing constitutes practically 

 the only use of this type at present and without irrigation the produc- 

 tion of this crop alone must continue. Good yields are the rule. It 

 is not believed that much headway toward intensive cropping can be 

 made without irrigation. Beyond doubt the soil is admirably adapted 

 to a variety of crops, making small holdings possible. Such irriga- 

 tion development as has taken place in the vicinity of Los Molinos in- 

 dicates that the type is well suited to alfalfa, the stone fruits, and a 

 great variety of general farm crops. It is a good soil and practically 

 its entire area is suited for subdivision into small farms whenever 

 irrigation is provided. 



