We’ve got a back 40 full of Oregon ash trees. Nice big old tall ones my wife can barely wrap her arms all the way around; robust saplings waiting in the wings; a kajillion sproutlings.
They’ve all recently been handed a “death sentence,” as has nearly every other ash tree in the entire Willamette Valley (and the rest of the Northwest). That’s going to be bad news for the valley’s suddenly robust coho population – which has posted record returns the past two years, markedly expanding a salmon fishery that has consumed no small portion of my free time in recent Septembers and Octobers – as well as its spring Chinook and winter steelhead, two other favorite pastimes of mine.
Oregon ash is the dominant tree in the Willamette Valley’s bottoms. It’s been dubbed “wetland supertree” – which should also tell you all you need to know about our backyard and its rainy-season streams and swamp. With their unique tolerance for the valley’s thick clay soils and moisture, ashes line waterways such as rivers, creeks and sloughs, and they tower over seasonally flooded areas, ponds and whatnot, helping to keep the water cool enough for young salmon and steelhead, trout and other species.
Their bane will be the emerald ash borer, an invasive insect that’s wreaked havoc on Midwest ashes since turning up there around the turn of this century. Illinois and Michigan report mortality rates greater than 99 percent for trees attacked by the half-inch-long, metallic-green bug originally from eastern Asia.
“At this point,” the U.S. Geological Survey has stated, “all ash trees in North America are threatened and [emerald ash borers] could ecologically eliminate them from North American forests.”…