4.1 The purpose of this standard is to provide common tree names and botanical names for commercial species and species groups but is not intended to be all inclusive of commercial practice. The decision about which commercial species are included in this practice is made by the D07 committee on wood.

4.2 Individual species are frequently mixed in commercial species groups for marketing or harvesting convenience, or for similar appearance or performance properties, or both.

4.3 Consumers of lumber, plywood, and other wood-based products may use different mixes of species for the same species group name. This practice should provide clarity for nomenclature used throughout wood-consuming industries.

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 541. 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 *. The names recognized under the American Lumber Standard are shown with a dagger (†).

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 PS 20, identify a commercial name applied only when the included species are harvested from Canada as (North) or the United States as (South).

1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.