The cam lifter feed mechanism of the invention comprises an inclined endless chain conveyor carried by an upper greenhouse gearbox framework and a lower framework including a multiplicity of lug-like lumber engaging means mounted at intervals on the endless chains of the conveyor, a driven shaft journaled for roatation in the upper framework including sprockets operatively engaged with endless chains of the conveyor, a plurality of cam lifters mounted on the shaft at opposite terminal sides of the endless chain conveyor including outwardly projecting hook-like foot portions getting operable to engage the lowermost terminal edge of lumber carried on the conveyor by the lug-like engaging means and to carry the lumber over the shaft to a point of discharge, a downwardly inclined discharge feed guide means mounted on the upper framework between cam lifters. The low framework having a pair of opposing hopper forming downwardly likely aspect frame users getting operable to guide lumber toward the limitless string conveyor, means mounting the endless string conveyor distally close to the lowermost end of the downwardly likely aspect body member. The hook-like foot servings each have got a leading edge downwardly likely with regards to the radii of the cam lifter at an angle coincident with the angle of inclination of the endless string conveyor, the foot part providing upwardly from the leading edge right into a connect forming portion.