Residual effects on pastures from fertilizers applied previously to wheat on experiments carried on between 1947 and 1951 in the zone from Cauquenes to Osorno are shown.
Residual effects of phosphorous is considerable in the first year pasture, but this effect is generally not so large than the direct effect on wheat. In the second year pasture, results are rather erratic, due to the condition of the pasture. Nevertheless, a top-dressing of 200 Kg./Há. of P2O5 on the second year pastured imporved greatly the yield of the pastures, which is an indication that the poor residual effect on the second year is probably related to the fixation by the soil of the phosphorous applied to the wheat (amounts of P2O5 applied to wheat raised up to 300 Kg./Há.).
Importance of top-dressing of pastures with phosphorous fertilizers in chilean agriculture is stressed.
These trials show also that liming has not the importance that phosphoric fertilization has for the maitenance Chilean pastures.

1 Ingeniero Agronómo. Sección Suelos. Departamento de Investigaciones Agrícolas