http://www.fs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb5409055.pdf - this item is still online as of feb 18 2023
the handbook is also available at web.archive.org/web/20230000000000*/https://www.fs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb5409055.pdf on the wayback machine / internet archive - 2/18/2023
handbook is also available at archive.is/https://www.fs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb5409055.pdf 2/18/2023