THE PILOT WAS PRACTICING A FORCED LANDING WITH AN INTENDED POWER RECOVERY AT 100 FT AGL. HE STATED THAT AS POWER WAS APPLIED TO GO AROUND, THE AIRPLANE ENCOUNTERED TURBULENCE AT TREETOP LEVEL & THE RIGHT WING DROPPED. HE APPLIED CORRECTIVE ACTION, BUT THE AIRPLANE SETTLED TO A FEW FEET ABOVE THE GROUND. HE ELECTED TO LAND, BUT DURING THE LANDING ROLL-OUT ON WET TERRAIN, THE AIRPLANE COLLIDED WITH A DITCH & WAS DAMAGED.