Western hemlock is a species that is highly susceptible to compression wood (CW) formation, an abnormal wood tissue that forms on the under side of leaning tree stems and branches. When lumber cut from logs containing CW is dried, the CW shrinks approximately 10 times normal in the parallel to grain direction, resulting in degrade, at times severe, due to warp in the form of crook and bow. In this project a technique using an ultrasonic materials evaluation system (UME) was tested for its ability to detect CW. Since stress wave velocity, in addition to being dependent on elastic properties and material density, is also a function of growth ring orientation, a slope of grain indicator was evaluated for its ability to measure growth ring orientation, to be used in conjuction with the UME.