The Emerald Ash Borer
Ash Salvaging in North America
If trees could read, they would probably disagree to call our activity “salvaging” – as we do nothing but try to get ahead of the “Emerald Ash Borer” (Agrilus Planipennis Fairmaire).
Its greedy larvae are killing any Ash tree their mothers could find, and as experience shows, sooner or later, they will find all of them. This metallic-greenish beetle originated in Asia and was probably brought to the United States with packaging material. It was first sighted in the State of Michigan in 2002 and since then spread out to most of the lower 48 States, devastating Ash trees in gardens, parks and forests. While some municipalities try to apply chemicals to save individuals in parks and alleys, Danzer opted for just harvesting the trees and utilize them as long as there is no major effect on timber quality.
Luckily, combining the detailed local knowledge of our experienced foresters with a state-of-the-art GIS, planning could be done quickly: we ranked management units by Ash total volume, volume per acre, % and average diameter. Thereafter, within the selected units, we zoomed into zones with high concentration of Ash.
In areas with significant volumes of Ash, extraction was limited to this specie, in order to minimize disturbances to the forest structure and also to get things done quickly and move on to the next tract – before the beetle does.
With this 1st round finished, now areas with 15 % or less of Ash volume are treated, adding tree stand improvements like thinning of overstocked areas and removal of lower-valued trees to the activities.
We are not happy about this, but try to harvest and utilize as much of the appreciated natural resource Ash-timber as we can. Hopefully, the natural dynamics of our mixed forests with its high diversity of in average 10 to 20 species per tract will heal the wounds soon.
Picture source: Emerald Ash Borer Information Network