Esforço tratório requerido por quatro arados no preparo do solo.

Abstract

Because primary soil tillage is considered the highest energy and time demanding operation, plowing is one of the refences for selection of tractor power. In a Terra Roxa Estruturada soil at the Fazenda Experimental Lageado, Botucatu, SP, operational variables were determined using four types of plows: Three moldboard plows (usual moldboard, special notched moldboard, and square plow), and one diskplow. Travelspeed, drawforce, drawbar power demand, and both specific force and power were evalueted. An experimental design of randomized blocles with six replications was used. The square plow presented lower travelspeed, both greater drawforce and specific force, than the other ones. There was no statiscal difference between treatments regarding mobilized soil area.