1.1 Commercial species group names are listed with common tree and botanical names. Commercial names are representative of commercial practice in the United States and Canada. Some foreign species that are used in the United States and Canada are listed in Appendix X1 with their commercial and botanical names.

1.2 The official common names conform to USFS AH 41. In addition to the official common name for a species, the checklist also lists other names by which the species and the lumber produced from it are sometimes designated. Names unique to Canada are shown with an *.

1.3 The designations in parentheses, (North) and (South), a convention used by the American Lumber Standard Committee (ALSC) accredited lumber rules writing agencies listed in NIST PS 20, identify a commercial name applied only when the included species are harvested from Canada as (North) or the United States as (South).