The durability of yellow-poplar and American beech treated with creosote and borate

Durability of yellow-poplar and American beech stakes treated with creosote and creosote/borate was evaluated in field plots in West Virginia and Miss issippi. Results suggest that the use of beech heartwood treated to a reten tion of 8.0 pcf (128.2 kg/m(3)) is justified when a use-life of 5 years is acceptable. Stakes of American beech heartwood and southern yellow pine sap wood treated with creosote and a creosote/borate dual treatment exhibited a n increase in durability performance with an increase in retention. Value o f the addition of borate for a dual treatment is not clear. Results for bee ch sapwood and all yellow-poplar stakes generally were not adequate for mos t, if not all, retention levels of either treatment used in this study.