Self cleaning fertilizer drive wheel

Claim 1

AN IMPLEMENT HAVING A TRAVELING FRAME, A GROUND WHEEL MOUNTED ON AND SUPPORTING THE FRAME, A DRIVEN IMPLEMENT PART MOUNTED ON THE FRAME, A DRIVE WHEEL CARRIED BY THE FRAME AND FRICTIONAL ENGAGEABLE WITH THE GROUND WHEEL, AND MEANS FORMING A DRIVING CONNECTION BETWEEN SAID DRIVE WHEEL AND SAID IMPLEMENT PART FOR DRIVING THE LATTER IN RESPONSE TO THE ROTATION OF SAID DRIVE WHEEL, SAID DRIVE WHEEL BEING DRIVEN BY ITS ENGAGEMENT WITH SAID GROUND WHEEL IN THE OPPOSITE DIRECTION THEREFROM AND ADAPTED TO SLIP WITH RESPECT THERETO AS A RESULT OF THE DRIVING LOAD ON THE DRIVE WHEEL IMPOSED BY SAID IMPLEMENT PART, SAID DRIVE WHEEL HAVING A TREAD PATTERN COMPRISING CIRCUMFERENTIALLY SPACED GENERALLY VSHAPED ELEVATIONS PROJECTING FROM THE PERIPHERY OF THE WHEEL, THE SLIPPAGE BETWEN THE ENGAGING SURFACES OF SAID WHEELS CAUSING DIRT PICKUP BY AND ADHERING TO THE PERIPHERY OF SAID GROUND WHEEL TO BE EXPRESSED LATERALLY OUTWARDLY BETWEEN SADI V-SHAPED ELEVATIONS.