Tannin-formaldehyde resins have been developed as fortifiers for starch adhesives used in the production of weather-resistant corrugated containers. Condensed flavonoid tannins, extracted from the bark of the black wattle tree, have replaced expensive petroleum-derived components in fortified starch formulations. Glue-mix variables have been optimized by means of factorial experiments and statistical treatment of results from tests of adhesion between plies of corrugated board. Factory production trials with tannin-fortified formulations have shown that borax could be eliminated from starch adhesives without detrimental effects on glue mix viscosities. In addition, higher machine speeds have been achieved with wattle-base fortifiers. Inexpensive tannin-starch adhesives have been used commercially in the manufacture of weatherproof corrugated containers for the export of fruit or for the storage and transport of beverages.