Published for the members of North Itasca Electric Cooperative
VOL. 20 NO. 11 - November 2017
Elm Project Updatecontinued
Trees like elm and ash help to draw down the water table to a functional level for other vegetation. Without them, species might die out and the land cover could change.
In the mid 1900s, the elm was devastated by the Dutch Elm Disease (DED). Now EAB is threatening the ash. But, if the National Forestís elm project is successful, the elm will return to replace the ash.
About ten years ago researchers looked for survivor trees on the Forest and other areas in the Midwest to test. Although some resistant trees had been developed and used in urban plantings, it was also necessary to develop trees that were cold hardy and had a wider genetic base that could respond to possible mutations by the fungus.
The resulting seedlings and crosses were brought to Minnesota five years ago, where about 1300 were planted on three sites in the Forest: near Walker, near Blackduck and on Highway 29 between Spring Lake and Wirt. After five years, about 15 percent were lost to the climate. The rest were cold hardy.
In mid June those trees, now about 10 feet tall, were inoculated with Dutch Elm fungal spores. After eight weeks researchers from Ohio and the Forest returned and looked for trees that had retained at least 75 percent of their canopies.
The result, said Flowers, was in line with expectations - around 10-20 percent showed tolerance to DED. Since trees can recover from a DED infection, they will get a second chance. Next June trees will be reassessed and those that have not shown tolerance will be culled.
Then restoration efforts will begin. In 2019, the project payoff will start: Trees will be propagated and seed collected in 2019, said Flower.
Return to the November 2017 Issue