OREGON FARMER 51 



rotations. Barnyard and green'manures together with the growing 

 of leguminous crops such as will add large amounts of humus, 

 give splendid results. With this sort of treatment and the addition 

 of reasonable amounts of commercial fertilizers, the fertility of this 

 soil will be greatly increased and its producing strength may be 

 permanently maintained for profitable cropping. Some of these 

 lands already farmed, have grown products of splendid quality. 

 (Composition, Table, Page 46.) 



The "Pumice" Soils. This peculiar type covers only a limited 

 area at the head of the Deschutes River in Central Oregon. It is 

 white, gray, yellow, or light brown in color and very coarse and porous 

 in texture, being made up largely of partially disintegrated pumice. 

 Pumice is a very soft, exceedingly light and fine grained porous 

 rock of volcanic origin, which might be most aptly described as 

 volcanic spume. The qualities and agricultural value of this 

 "pumice" soil are as yet largely undetermined. The plant food con- 

 tent appears to be reasonably good, but the peculiar physical charac- 

 ter (lightness in weight, and great porosity), combined with the 

 rather high altitudes at which it is found, make the best use and 

 production possibilities of this soil, problematic, and its ultimate 

 use and value are yet to be determined. Because of its peculiar 

 physical qualities, its mechanical composition is not given here. 



The "Alkali" Soils. Because of the heavy rainfall, alkali soils do 

 not occur west of the Cascades in Oregon. In Eastern Oregon 

 practically all of the soils are moderately alkaline in reaction, but 

 only sufficiently so to make this quality of great value in offering 

 desirable soil conditions for crop production. Only in those areas 

 of the semi-arid districts where the land lies so flat or pan-like as 

 to lack good natural drainage does the alkali become so excessive 

 in amount as to be injurious to crop production. The presence 

 of injurious amounts of alkali is indicated in dry weather by the 

 appearance on the surface soil of the whitish powder or crystals 

 of the "white" alkalies, or the blackish brown stains of the "black" 

 alkali; but at any time of the year the absence of the heavy black 

 sage and the presence of such alkali-resistant plants as greasewood, 

 saltbush, saltgrass, etc., together with the observable lack of natural 

 drainage, are good indications of the presence of excessive amounts 

 of salts. Such areas are to be avoided, unless the land can be artifi- 

 ficially drained and irrigated. On irrigable lands, artificial drainage 

 followed by flooding with irrigation water will wash out excessive 

 alkali, and the use of heavy dressings of barnyard manure and green 

 manures together with deep plowing and thorough summer culti- 

 vation to stop surface evaporation of moisture, will reduce and dis- 

 tribute the alkali so that profitable production may become possible. 



On dry farming lands strong alkali areas are very undesirable. 

 While deep plowing and the addition of organic matter, greatly 

 improve such areas and in many cases entirely reclaim them, yet 

 for the most part strongly alkaline spots in the soil are to be avoided 

 for this type of farming. In portions of Central Oregon, alkali 



