On July 3, 1999, at 0800 central daylight time, a Grumman-Schweizer G-164B, N6633K impacted crops and terrain on takeoff from runway 35 (2,600 feet X 30 feet/dry asphalt) at Page Regional Airport, Page, North Dakota. The instrument rated commercial pilot reported no injuries. Visual meteorological conditions prevailed during the 14 CFR Part 137 aerial application flight. The airplane was not on a flight plan. The flight was originating at the time of the accident. The pilot stated that he had 375 gallons of chemical and water mixture and 60 gallons of 100 low lead fuel onboard. The pilot said that the local temperature was around 70 degrees Fahrenheit and winds were 7 mph out of the northeast. He stated that the aircraft ran up normally. He said that he checked the windsock in the run up area and it was still indicating wind out of the northeast. He said that on takeoff the airplane rotated and started to fly. He stated that the airplane did not produce any further lift and he impacted corn and terrain off the departure end of runway 35. After the accident he said that he noticed the wind shifted to the southeast.