Four alternative anti-sap stain chemicals were subjected to a four month field evaluation during the summer of 1980. The test, established at a Vancouver Island sawmill, was designed to evaluate the potential long-term effectiveness of sodium tribromophenate (Velsicol Ltd.), Biocom XX (Bramco Industries) containing methylene bis-thiocyanate, Woodbrite NTX (Van Waters & Rogers Ltd.) containing 3-iodo-2-propynyl-butyl carbamate and Mitrol 48 (Kenogard) containing guazatine acetate and quaternary ammonium chlorides, on hemfir and Douglas fir. Sodium tribromophenate was found to give surface protection equivalent to that of chlorophenate treated controls. Biocom XX was also effective, although the active ingredient came out of solution at the required treating solution concentration. Woodbrite NTX and Mitrol 48 were found to be ineffective on either species group under the test conditions.