Attachment combination for agricultural tractors

Attachment combination for agricultural tractors for loosening soil in a field preferably covered with living or dead plant or crop residues, comprising a covering hood forming an ejection channel, a motor-driven flail mower disposed under said covering hood, at least one row of loosening elements disposed behind said flail mower, a support tube for said loosening elements, and motor-driven tools rotating behind said loosening elements for crumbling the loosened soil, wherein said flail mower hood is arranged to discharge in one of a first position and a second position so that in the first position said hood discharges before the front side of the support tube of the loosening elements in a direction slanting backward and downward and in the second position discharges beyond the loosening elements and the rotating tools for the crumbling of the soil disposed behind them, characterized in that said flail mower is mounted on a rearwardly open U-shaped support frame (1) which consists of at least one cross beam (2) extending crosswise to the direction of travel and of at least two laterally spaced longitudinal beams (3) extending in the direction of travel from said cross beam and each having a free end, a coupling piece on each said free end of said beams (45a), a counter-piece (45b) clamped on the support tube (46) of the loosening members and said coupling piece connected for easy detachment with said counter-piece.