A wood splitting assembly includes two wood splitting stages mounted on a trailer or truck bed. A first stage for splitting large diameter wood pieces is adapted to be transported in a substantially horizontal orientation to be pivoted to a vertical orientation for use. A horizontal second splitting stage is mounted horizontally. A double stage hydraulic system enables independent reciprocation of the two wood splitting stages independently of each other and is powered by a single motor for driving the hydraulic pump. Preferably a platen at the bottom of the vertical splitting assembly is located a distance from the pivot axis sufficient to engage a level ground surface and thereby to relieve a portion of the weight of the vehicle from a wheel thereof when in a vertical orientation.