Dutch Elm Disease Control: Sanitation Improved by Girdling Infected Elms

Abstract

For 5 years three alternative treatments to improve the efficacy of municipal sanitation programs for controlling Dutch elm disease (DED) were compared to the sanitation practice in which one disease survey was made each year and diseased elms were removed in late fall and winter. Significant reductions in DED were obtained in treatments where three disease surveys were conducted each year and diseased elms were promptly removed. In the treatment in which diseased elms were girdled, fewer elms became diseased in subsequent years. Spraying the trunks and major branches of diseased elms with hydraulic applications of methoxychlor did not significantly improve DED control.