The Delta is designed to cultivate in a wide variety of soils including shallow soils over rock, and those with a high stone content. A heavy duty spring break back mechanism protects the cultivator when large rocks are encountered and the pivoting geometry enables the leg of the tine to move up and rearwards thereby passing over the obstacle before immediately penetrating back to its previous cultivating depth. In addition to the spring mechanism the leg is protected by a shear bolt. The shear bolt may be fitted in either of two holes which provides differing penetration and tine operating angles a real benefit in hard soils.