During departure from runway 19, a 2,500-foot long, by 60-foot wide runway, the airplane "experienced difficulty climbing." When the flight instructor realized the airplane would not be able to clear trees at the end of the runway, he performed a forced landing to a field. During the landing, the airplane impacted a sign, resulting in substantial damage. The flight instructor reported no mechanical deficiencies with the airplane, and additionally stated that the wind conditions were "gusty" at the time of takeoff. He reported that the maximum gross weight of the airplane was 1,220 pounds, and the airplane weight at the time of the accident was 1,171 pounds. He stated the accident could have been prevented if "only one person was onboard the airplane, as the horsepower was marginal with two people onboard." He also stated that he should have been more aware of the changing wind conditions. The closest recorded weather observation, from an airport 27 miles to the northwest, included winds from 230 degrees at 11 knots, gusting to 21 knots.