UW News

August 5, 2010

Campus losing another tree to Dutch elm disease

The campus will soon be losing one of its venerable elm trees. The easternmost elm tree on the south side of Gerberding Hall is showing serious signs of Dutch elm disease, according to UW arborist Sara Shores. To stop the spread of the disease, prompt removal of the infected tree is required.

“All three of the elms near Gerberding have been inoculated with Dutch Trig, a treatment that is not 100 percent effective against Dutch elm disease,” Shores said. “The poor soil and growing conditions, lack of automatic irrigation and last year’s drought probably contributed to the trees being more susceptible than most.”

The disease is spread both through the elm bark beetle and root graft, Shores said. Dutch Trig does not protect against the spread of the disease through root grafting, so the UW plans to trench in between the remaining trees to try to save the middle tree from possible infection.

“It is very possible this tree is already infected and the elm on the west is showing early signs as well,” Shores said. “We plan to remove the easternmost tree first and will continue to monitor the health of remaining two trees.”

Last year, some of the elms on Parrington lawn had to be removed because of Dutch elm disease.