According to the flight instructor, he was demonstrating a soft field landing to a grass runway in a tricycle-gear airplane. During the landing roll on runway 34, a “strong wind gust from the right” lifted the airplane’s right wing, and the airplane “slid sideways to the left.” The student pilot noted that the airplane had landed “midline,” and after the gust of wind struck, the nose of the airplane headed left even though the instructor had applied full right rudder and aileron. The airplane’s left wing subsequently grazed small tree branches, then impacted a bigger branch that rotated the airplane counter-clockwise. The airplane came to rest perpendicular to the grass runway, with the airplane’s nose facing into the trees. The airplane’s left wing tip and right wing leading edge were substantially damaged. The flight instructor and the student pilot reported there were no mechanical malfunctions or failures of the airplane. Weather, reported about 9 miles east of the accident site, included winds from 320 degrees at 12 knots, gusting 17 knots.