March will mark the beginning of a city wide search for the over wintering and breeding habitat of the Elm Bark Beetle. This effort is critical in the battle to save Bismarck’s elm trees from devastating losses to Dutch Elm Disease (DED).
City arborists will begin combing the city March 2, looking for firewood piles that might contain elm wood. If elm wood is found, it will be marked with orange paint to aid the homeowner in the identification process. Wood owners will be asked to debark, burn or dispose of the over wintering elm wood habitat within ten days of notification. A notice describing the elm bark beetle lifecycle and how they use elm wood as a breeding and over wintering habitat will be left at the property where the elm wood is found. The notice also describes how to identify elm wood from other common firewood types found in North Dakota.
According to the NDSU Extension Service publication Dutch Elm Disease, “A few elm logs secreted away by one homeowner who does not understand the importance of the problem can undo all attempts at thorough sanitation and watchful disease surveillance for an area of several city blocks.”
Bismarck’s Dutch Elm Disease prevention program has been successful in large part due to the elimination of habitat that this disease vector uses to make it through our harsh winters. The insulating effect of a firewood pile allows many insects to survive in our frigid environment. Elm Bark Beetles use elm wood with tightly attached bark for protection from the extreme fluctuations of temperature that can kill many insects. By eliminating elm wood before spring, the over wintering beetles are destroyed before they can emerge in the steadily warming temperatures.
The Forestry Division attributes their success in fighting to save Bismarck’s elm trees to three main factors:
• Diligent inspections in the summer to identify diseased trees
• Quick removal of diseased trees from the urban forest once they are identified as a positive host for the fungus that causes Dutch Elm Disease
• Eliminating the over wintering and breeding habitat of Elm Bark Beetles by enforcing the required debarking or disposal of dead elm wood and stumps
Since Bismarck’s first positive identification of Dutch Elm Disease in 1977, there has been only one year in which Dutch elm disease losses have numbered more than one percent of the total elm population. We are committed to preserving our stately elms, and keeping the level of tree loss due to Dutch Elm Disease at less than one percent.