Two soils representative of the coast and three representing the Willamette Valley have been studied for their general chemical
characteristics. Exchange capacity and exchangeable cations were
determined by the ammonium acetate and the BaCl₂-triethanolamine
buffer methods. Exchange capacity was also obtained from conductimetric
titrations which were run on each soil...
Representative sites of the Dayton, Woodburn, Jory, Quillayute, Astoria, Willamette, Walla Walla, Deschutes, Laki and Owyhee soil series were investigated for seasonal changes in exchangeable potassium in air dry samples. No consistent seasonal variations were found which could be attributed to wetting and drying in the field. Cropping reduced the...