ABSTRACT
Influence of the residue on the productivity of the natural pasture, under arid Mediterranean climatic conditions

Fernando SueIla N.1 y Raúl Meneses R.2
 

This study was done at the Los Vilos Experiment Substation (INIA; lat. 31°51' S; long. 71°30' W), during 1981, 1982 and 1983. Treatments were: 0, 300, 600, 900 y 1,200 kg D.M. of residue/ha. Forage production and botanical composition were stimated during spring, by cut and point quadrat methods, respectively; bare soil and pastoral value were cIculated. In spite of different rainfall regimes, a significant difference (P < 0.01) in forage production was obtained in al) seasons, as residue increased (averages: 1,656; 1,871; 1,986; 2,325; and 3,011 kg DM./ha, respectively). According to a simple regression analysis, the linear adjustment was the best (r2 0.92). Botanical composition showed an increase of Piptochaetium stipoides and Avena barbata and a decrease of Plantago hispidula, with higher levels of residue. This last species denotes a Iow pasture condition. Pastoral values fluctuated between 15.2 and 20.2, higher values were concurrent with the higher residues.

Keywords:
1 Estación Experimental La Platina (INIA), Casilla 439, Correo 3, Santiago, Chile.
2 Subestación Experimental Los Vilos (INIA), Casilla 40, Los Vilos, Chile.