Results of the following trials made on “trumao” soils (Andepts), of the IX Region are presented:
- Two trials on date of the beginning of fallow x fertilization.
- One trial on methods of preparation of soil x depth of labour.
- Two trials on methods of soil preparation x nitrogen.
The main results of these trials are:
- A long fallow produced the higher yields, but a postpo’nement of three months in the iniciation of the fallow didn’t affect yields too much, pro vided N and P were applied.
- The systems of soil preparation combining deep plowghing without turnover arid a good level of pulverization of the roots of perennial grasses (chisel at 25 cm. depth plus rotatory plowghing at 8 cm. depth) yielded about the same than traditional plowghing (at 25 cm. depth) provided N and P were applied.
- Zero tillering, accomplished with a grassland-rege nerator and gramoxone application, yielded a Iittle less than traditional plowghing and than mi nimum tillage.
1 Ing. Agr., Programa Manejo y Ecología. Estación Experimental Carillanca, Instituto de Investigaciones Agropecuarias (INIA), Casilla 58-D, Temuco, Chile.