The glider pilot reported that, during an aerial tow, about 200 ft into the takeoff roll, the glider weathervaned to the left and ran off the side of the runway about a foot. He was unable to correct because of the low airspeed. He added that the paved runway surface and soft dirt off the side of the runway were extremely bumpy and he was concerned about breaking the landing gear. The tow plane was "effectively dragging [the] tail through the dirt" and by the time the glider had built up enough speed to utilize the rudder, he was about halfway down the 1,270 ft runway. The pilot added that the tow airplane lifted off before the glider. The glider lifted to about 10 to 15 ft above the runway and remained in ground effect. The tow airplane and glider drifted to the right of the runway over sage brush. The glider lost airspeed, settled, impacted the sage brush, and cartwheeled. The pilot added that his GPS flight track displayed a maximum ground speed of 52 knots. The glider's stall speed for his configuration was about 51 knots. The manufacturer published on their website that the stall speed was 32.4 knots. The tow pilot reported that, during the takeoff, he saw in a mirror that the glider was "extremely low, with a nose high attitude" before impacting sage brush. The glider sustained substantial damage to the fuselage and right wing. The pilot reported that there were no preaccident mechanical failures or malfunctions with the glider that would have precluded normal operation. The glider pilot reported that the wind was variable and from 190° at 10 knots, gusting to 20 knots. The tow pilot reported that the wind was variable from 190° to 210° with gusts from 5 to 15 knots. The pilots were departing runway 21.