The pilot elected to use a short field takeoff technique to ensure that the aircraft cleared a termite mound alongside the direct takeoff path. The hot day and the sandy strip surface combined to lengthen the takeoff roll required. The aircraft deviated towards the termite mound during the takeoff run, and the pilot was forced to rotate at a lower than normal airspeed. As the aircraft passed over the termite mound in a high nose up attitude, the tailplane struck the mound causing substantial damage to the tip of the tailplane and the elevator. The pilot did not associate the slight bump felt with mound contact. No adverse flight characteristics were noticed during the short flight to the destination. The damage was observed, by the pilot, during the after flight inspection.