While landing the pilot touched down and the airplane began to porpoise. The pilot then added power and attempted to land again. The airplane once again touched down and began to porpoise. This time the pilot decided to do a go-around. During the go-around he did not feel he was going to clear some trees and decided to put the airplane down in a field. Upon touching down in the field, the nose landing gear and right main landing gear collapsed. The left wing, right wing, and fuselage incurred substantial damage. The pilot stated that there were no mechanical issues and the engine was producing full power but, the airplane only had about a hundred horsepower and he did not feel as though he was gaining enough altitude. He also stated that he was “behind” the airplane during the go-around. Examination of the airport and accident site revealed that during the go-around, the airplane had made ground contact off the right side of the runway, became airborne again, flew over the top of a fence, and then touched down in the field. Examination of the airplane revealed that carburetor heat control was "ON". The push-pull type throttle was in the full open position, and the mixture control was in the full rich position. Review of the airplane's owner's manual revealed that if a porpoise was encountered during landing, a go-around should be executed by applying full power immediately and shutting "OFF" the carburetor heat. Further review of the owner's manual, along with the weight of the occupants, and the fuel on-board, revealed that during the occurrence, the airplane was being operated close to its published maximum gross weight.