Hernán Tejeda S.1 y Gerald L. Gogan2
Different laboratory methods to estimate nitrogen availability in Ñuble soils were evaluated.
Soils with four different parent material, recent and ancient volcanic ash, granitic rock and glacial-alluvial deposits, were included in the study, grouped into two categories. Soils derived from recent volcanic ash, which are high in organic matter, were grouped under the name of trumao soils. Soils from the other three origins are maderate to low in organic matter and were arbitrarilly grouped under the name of non trumao soils.
1Ing. Agr. M. S., Estación Experimental Quilamapu, Instituto de Investigaciones Agropecuarias. Casilla 426, Chillán, Chile.
2Agronomist, M. S., Voluntario del Cuerpo de Paz (U. S. A.), Escuela de Agronomia, Universidad de Concepción, Chillán, Chile. (Dirección actual: Agronomy Department, Iowa State University, Ames, Iowa, U. S. A.