THE DEPARTURE END OF RWY 31 IS OBSTRUCTED BY POWER LINES, TREES AND A MOTEL. THE STANDARD PROCEDURE IS TO DEPART ON RWY 13 AND LAND ON RWY 31. THE FIRST 1,000 FT OF RWY 13 IS COVERED WITH A CHEMICAL MIXTURE TO PREVENT DUST. THIS MIXTURE FORMS A CRUST, AND, WITH BLOWN SAND ON IT, THE RWY BECOMES SLIPPERY. WHILE IN THE PATTERN FOR RWY 31, THE PILOT SAID THE WINDS WERE SSE AT 5 TO 10 KNOTS. AFTER TOUCHDOWN THE APPARENT GROUND SPEED INCREASED WHILE THE INDICATED AIRSPEED RAPIDLY DECREASED CONCURRENT WITH A RIGHT DRIFT, INDICATING A SUDDEN AND STRONG LEFT QUARTERING TAILWIND. AT THE HALFWAY POINT, THE INDICATED AIRSPEED WAS INSUFFICIENT TO GO AROUND WHILE THE POOR BRAKING ACTION WAS NOT STOPPING THE AIRCRAFT. THE PILOT SAID HE REALIZED THE AIRCRAFT WAS GOING TO OVER RUN THE END OF THE RUNWAY AND THE PILOT ELECTED TO TURN INTO THE TREE LINE AND COLLIDED WITH TREES AND A MOTEL FENCE. A LONGER RUNWAY MORE ALIGNED WITH THE WIND DIRECTION WAS AVAILABLE.