Absorption of Nutrients from Subsoil in Relation to Crop Yield

Root behavior and crop yield under irrigation /

“…A continuation of these studies with field crops showed that this variation was sometimes so great and the root habit so profoundly changed that the roots were scarcely recognizable as belonging to the same species (Weaver et ah, 1922 : 69). Crops grown in soil of high fertility have roots that are shorter, more branched, and more compact than those in similar but less fertile soil, as has recently been confirmed by Crist and Weaver (1924). Marked contrasts in the degree of ramification of roots as they penetrate different soil strata may be attributed in part to differ¬ ences in soil fertility (Bowman, 1911 : 66).…”

Summary and Interpretation of Underground Development in Natural Grassland Communities

“…Absorption of both water and nutrients at great depths has been adequately demonstrated (Crist & Weaver 1924, Hunter & Kelly 1946. Absorption of both water and nutrients at great depths has been adequately demonstrated (Crist & Weaver 1924, Hunter & Kelly 1946.…”

“…VARIOUS SOIL TYPES Knowledge of the soil as a medium for growth of roots has increased very greatly in the past 30 yrs. Absorption of both water and nutrients at great depths has been adequately demonstrated (Crist & Weaver 1924, Hunter & Kelly 1946. Moreover, it has been found that during the period of heading and ripening of seed the deeper portions of the root system often absorb most actively.…”

The Recovery of Fertilizer Nitrogen From Various Depths Below Swards

“…Since the major portion of the roots of grasses in this country occurs close to the soil surface, little attention has been paid to the role of the relatively fewer roots occurring at deeper depths. Some early work by Crist and Weaver (1) showed that grasses were capable of absorbing considerable quantities of water and nutrients at depths below one foot. In a sward, Midgley (2) showed that superphosphate applied in 6 inch grooves, and spaced 4 inches apart gave higher yields of dry matter than similar dressings broadcast on the surface.…”