During late summer and early fall in Manitoba, adult native elm bark beetles (NEBB) that carry Dutch Elm Disease (DED) emerge from brood galleries in the canopy and upper trunk of infected elm trees and move to the base and root flares of healthy trees to overwinter. In the spring, DED-carrying beetles disperse from these overwintering sites back to the canopy of healthy elm trees where they feed and construct new brood galleries, thus introducing new DED infections. The current practice after initial DED diagnosis is to remove diseased American and Siberian elm trees prior to emergence of overwintering adult NEBB vectors before the spring. In Manitoba and Saskatchewan, the preferred date for infected tree removal is before the end of March. In Winnipeg, the majority of trees are removed during late fall and winter although infected trees may remain standing into early summer. Infected tree removal remains a vital and primary component of the integrated DED program in the City of Winnipeg, even though other DED management methods are practiced to augment infected tree removal, including insecticidal control of beetles, injection of fungicides for tree protection, sanitation pruning, etc. A significant constraint to this approach is that most infected trees are removed after NEBB adults have emerged in the fall and moved to overwintering sites on healthy trees. Delayed removals due to weather conditions, site accessibility and limitations in resources needed to remove trees have also resulted in infected elm trees remaining in place until the spring. All these issues diminish the success of the elm sanitation program. Removal of all diseased trees before mid-September could potentially reduce NEBB populations and thus, DED incidence, and spread. Logistical limitations are encountered when large numbers of infected trees require immediate removal, and it is impractical to remove that number between July and September. Preliminary research by Holliday (2016) suggested that a small percentage of diseased elm trees ...