HOOD EIVEK-WHITE SALMON RIVER AREA. 23 



light grayish brown in color and entirely free from either rock or 

 gravel. 



The stream-laid or alluvial soils of the area are represented by the 

 Wind River, Columbia, and Winans series, and by a nonagricultural 

 type mapped as Riverwash. 



The soils and subsoils of the Wind River series are light brown or 

 light reddish brown. The series occupies Jiigh terraces, sometimes 

 several hundred feet above the present valley bottoms, and is 

 underlain by a stratum of gravels or of basaltic rock, although this 

 is not generally encountered within the depth of 6 feet. Of tliis 

 series the stony loam, gravelly sandy loam, sandy loam, loam, and 

 fine sandy loam members have been recognized. These soils are of 

 considerable importance, and occur in both the Hood River and 

 "WTiite Salmon River Valleys. (PI. V.) In one or two instances 

 glacial till deposits occur as a substratum beneath some of the types 

 and a part of the stratified gravels and sands found sometimes in the 

 subsoils may be glacial outwash deposits. 



The soils of the Columbia and Winans series and Riverwash are 

 confined to the stream bottoms, and are of recent alluvial origin. 

 The Columbia series is represented only by the Columbia fine sandy 

 loam. This is a light grayish brown or buff-colored soil underlain 

 by stratified alluvial deposits which vary in texture. The parent 

 material is derived from a ^\^de variety of quartz-bearing and quartz- 

 free rocks, and most of it has probably been transported long dis- 

 tances. The type occupies the present flood plain, and much of it 

 is subject to overflow, but where sufficiently elevated above the level 

 of the stream it is cultivated. 



The Winans series occupies narrow areas of low terrace and bottom 

 lands in the Hood and White Salmon River Valleys. The soils and 

 subsoils are typically light brown or grayish brown in color and 

 underlain by a substratum of stream-laid gravels. The series is 

 represented by two types, a gravelly sandy loam and a loam. As 

 mapped, however, these two soils include some undifferentiated mate- 

 rial which in a more detailed survey, or if occurring in more exten- 

 sive bodies, would be recognized as distinct soil types. The parent 

 material is derived predominantly from basaltic rocks and much of 

 it has been transported but a short distance. 



The gravelly sandy loam is confined to narrow, irregular bodies 

 along the Hood River, and usually occupies areas of low terraces 

 above the present level of the stream channel. This type is very 

 graveUy, the gravel consisting both of glacial and water-worn rock. 

 The formation of the soil is largely due to the reworking by alluvial 

 agencies of bodies of glacial till. The surface is moderately sloping, 

 except immediately along the river, where the land surface often 

 drops abruptly to the level of the stream. The type is traversed by 



