Death is of course, a natural outcome of life, but the death of an entire species is more than sad, it is tragic and unrecoverable. In a few short years, the damage brought about by the rapid incursion of the invasive Emerald Ash Borer has had a devastating impact on the flatlands along the low end of our property, as Coshocton County joins the rest of Ohio, mourning the apparent loss of yet another prominent tree species.
Although not one of our property’s more prominent tree species, the swampy area across our northern face is dominated by small and bushy Alder trees, and dozens of tall Ash trees that grew up after farming ceased, some time in the mid 20th century. Seemingly healthy just two years ago, signs of significant woodpecker activity were apparent last summer, suggesting an unusual insect infestation. In January, it was easy to see how pockmarked many of the ash trees had become, from the woodpeckers trying to extract the fat juicy larvae, and the worms boring back out of the tree to mate and infect the neighboring Ashes.
The exterior of an infected ash tree fails to make clear the degree to which the borers crisscross the living wood layers immediately underneath the bark. The effect is the same as girdling the tree, cutting off the flow of sap and nutrients to the tree’s canopy, which usually dies within a few years.
Although they appeared fully leafed out last year, the ash trees lining our township road now appear mostly dead, with only a few scraggly outbreaks of leafs in the crowns, and an almost poodlelike outbreak of leaves around the trunk and lower limbs, as the trees desperately try to spread a few leaves in the summer sun. The smaller ash trees in the interior, feet wet in vernal pools, have already died (camera right, above). Only a couple of the ash trees seem to have a full canopy this summer (camera center shows an ash tree in front in lighter green, with a darker green hickory behind it, flanked by dead and dying ash).
A quadrant of 18 inch diameter trees along the creek bank, apparently the mother trees that seeded our part of the valley, still looked healthy last January, but are now showing signs of woodpecker damage, and branches in the canopy are failing. It seems only a matter of a few short years before these lovely giants fade, too.
The stark appearance of a leafless and dead tree jumps out of a forest of green trees. Even in the winter, there’s something different in the appearance of a dead and decaying tree, in comparison to one that is only taking a few months rest. While 1-3% of forest trees die every year, the victim of disease, wind, and competition, in a short 13 years, millions of Americans ash trees have fallen to this latest scourge. The highways and country lanes of Franklin, Knox, and Licking counties between us and Columbus are punctuated by long lines of dead and struggling ash trees, and the roadsides in our neighborhood are beginning to show the inevitable results of a tree species that is helpless against a beetle that evolved on some other part of the planet.
Several of the ashes near the dying trees are showing no obvious signs of distress, but their near mortality seems inevitable. Farther uphill, and a few hundred yards away from the flat area with the dying trees, several small stands of very tall ash seem to be thriving within a dense stand of maple and oak. Some research indicates that EABs prefer trees in the open. Heroic chemical action can sometimes save single trees in the city, but there are just too many trees to spray in a rural setting. Our choices are to harvest our trees, which are the classic wood used for baseball bats, or to leave them as woodpecker havens. In some ways, this latest tree die off parallels what happened 40-50 years ago, when Dutch Elm Disease spread across Ohio, destroying millions of beautiful fan shaped shade trees. When my parents’ bought the Hollow in the early 70s, there were many elm trees, dead, but still standing. A new generation of elm trees grew up from seed and sapling, with many of them reaching over 40 feet tall. As many of the medium and small elms dotting the base of our pond’s dam began dying over the previous several years, I hadn’t recognized yet what was happening. It wasn’t until our largest, and most classically shaped elm (below) began losing its leaves that I understood that our region was being revisited by another round of elm disease, which is now taking advantage of the regrowth in our elm population. This has killed a number of trees in the areas where we spend most of our time.
Taking are required classes in forestry has been a great learning experience for me and Elizabeth, but we’ve also lost some of our blissful ignorance. A growing variety of insects and diseases are threatening other species in Ohio. In the 1970s, lovely white dogwoods covered our hillsides in the springtime, but now, I can almost count our dogwood trees on my fingers. While changes in the overall canopy, and a reduction in open space have reduced our dogwood habitat, its hard not to believe that Dogwood Anthracnose hasn’t played a role. While it is still relatively rare, Oak Wilt would potentially be a huge impact on one of our most common and our most economically valuable trees. I don’t find the walnut trees to be especially pretty to look at, but they have lovely and valuable wood, and most falls provide us with a large crop of inconvenient but tasty nuts. Thousand Cankers Disease is not yet impacting Ohio walnuts, but the state foresters are on the lookout for it. The Asian Long-Horned Beetle hasn’t made inroads into Ohio, yet, but could potentially destroy the hundreds of sugar and red maples on our property. There doesn’t seem to be any specific disease impacting black cherries, which are a surprisingly short-lived tree, but there seem to be an exceptional number of our larger cherries that are sustaining heavy woodpecker damage, which indicates fatal levels of insect infestation, which probably also means fungus.