S2In West Virginia, yellow-poplar (Liriodendron tulipifera) is abundant and is a prime candidate for increased utilization in a variety of manufacturing industries. Computer simulations are a cost-effective tool for estimating potential cutting yields from lumber. They can be used to promote increased use of yellow-poplar in the furniture, cabinet, and architectural woodworking industries and may also lead to increased utilization of the lower grades of lumber. This paper describes the data collection methods and the format of the new West Virginia yellow-poplar lumber defect database that was developed for use with computer simulation programs. The database contains descriptions of 627 boards, totaling approximately 3,800 board feet, collected in West Virginia for grades FAS, FASIF, No. 1 Common, No. 2A Common, and No. 28 Common.S3.