Abstract: The invention relates to polymer/wood fiber composite structural members that can be manufactured in an extrusion process engineered to produce the highest quality materials. The composite can be in a linear extrudate or pellet and can have a cross-section of any arbitrary shape, or can be a regular-geometric or of arbitrary-amorphous shape. The extruded material comprises a consistent proportion of polymer, wood fiber and water. During the extrusion, water is removed intentionally to dry the material to a maximum water content of less than about 10 wt-% based on the pellet weight. To make a structural unit, the pellet is introduced into an extruder apparatus wherein, under conditions of controlled mass throughput, shear, mechanical energy input, controlled temperature and pressure, the composite material is produced.