Every spring, Portland’s elm trees wake up with extraordinary beauty from the long winter rest. Bright green leaves, small round seeds and microscopic green flowers greet walkers in Portland’s neighborhoods and parks. But behind these beautiful scenes there is a silent stalker that threatens every one of our City’s Elms – the deadly duo of Ophiostoma ulmi and Ophiostoma novo-ulmiI. Known collectivey as Dutch Elm Disease.
Ophiostoma grows in the elm’s vascular system starving the tree of water. Once an elm is infected death is quick, with leaves browning and the dead bark provided habitat for the elm bark beetle. A quick removal is the best hope of preventing the fungi from spreading to nearby elm trees by root grafts or the elm bark beetle.
Portlanders are vigilant about fighting the spread of DED, this year Save our Elms in Eastmoreland and Ladds Addition inoculated 115 Street trees and Portland Parks & Recreation inoculated 148 park trees to prevent the spread of Ophiostoma. But each year we loose a few of our most majestic elms to DED, and 2014 is no different, with Portland loosing 35 elm trees including 18 street trees, 2 park trees and 15 yard trees.
We are thankful to the great work of Urban Forestry Elm Monitor Emily Wilson, Save Our Elms and the many Portlanders who helped identify DED infected trees to insure a quick removal. For more information on how to spot DED, the DED management program and the 2014 DED Report, please click here.
Top: Portland Parks & Recreation Urban Forestry removing Elm street trees at SE Ladd Street and (top right) SE Ankeny. Above: Elm stump in the South Park Blocks, and (above right) Elm Monitor Emily Wilson (center) with Parks and Portland Public School staff at Richmond Elementary School, SE 47 and Division.