THE PILOT REPORTED HE WAS ATTEMPTING TO TAKEOFF WITH HIS TAILWHEEL AIRPLANE FROM A ROUGH, PRIVATE AIRSTRIP. HE SAID THE AIRPLANE WAS BOUNCING DURING THE PRETAKEOFF TAXI, AND HE WAS UNABLE TO READ THE CHECKLIST. HE SAID HE NEGLECTED TO LOWER THE WING FLAPS, AND THE AIRPLANE FAILED TO BECOME AIRBORNE BEFORE RUNNING OFF THE END OF THE RUNWAY AND NOSING OVER. THE PILOT ATTRIBUTED THE ACCIDENT TO HIS FORGETTING TO LOWER THE FLAPS. HE ALSO NOTED THAT GUSTING WINDS AT THE DEPARTURE END OF THE RUNWAY WERE CAUSING LOCALIZED DOWNDRAFTS.