#HTE
Bug-Borne Tree Disease Affecting Black Walnut is Spreading from West Coast to East Coast of America
American black walnut is a wood that’s prized by many. It’s relatively stable, easy on the eyes and has that beautiful chocolate-y color that looks so good that I sometimes want to eat it.
It’s no surprise that it’s become the go-to wood for many a furniture designer, and Shannon Rogers, the man behind our latest Introduction to Wood Species series, reports that recently boatbuilders have even been using it to replace teak. (While pricey, walnut is still cheaper than teak.)
Like many wood species, walnut is susceptible to bugs. Certain types of bugs like to burrow into trees, eating the sugary goodness inside and laying eggs.
This can be disastrous when said bugs are carrying disruptive payloads. Walnut is susceptible to an ailment bearing the attractive name of Thousand Cankers Disease, or TCD, which can be spread when Walnut Twig Beetles have picked up a dusting of spores from a fungus called Geosmithia Morbida. As the beetles burrow into the tree, they thoughtfully carry the spores inside with them. The fungus then begins colonizing the tree, disrupting its natural internal processes.
The result is that the tree starts developing cankers, and since the disease is not called Dozen Cankers Disease, you can probably do the math.
Until recently TCD was, like the Kardashians, just a west coast problem. But sometime around the 1990s the disease began to spread—theories suggest it was from wood or firewood containing the beetles being transported interstate—and by the 2000s was present in California, Oregon, Washington, Utah, Idaho, Colorado, Arizona and New Mexico. This is where we were at in 2009:
Then, in 2010, the disease popped up as far east as Tennessee. (Some reports say 2011 was the year of the Tennessee outbreak, but the date on this video suggests otherwise.) By 2015, here’s how far the disease had spread:
As you can see, Core77’s New York headquarters (which is admittedly not located within a copse of walnut trees) hasn’t yet been hit, but “it could come into New York at any time,” Karen Snover-Clift, Director of Cornell University’s Plant Disease Diagnostic Clinic, told Syracuse.com. “If it can survive in Pennsylvania, I’m sure it can survive in areas of New York.” While TCD has not been detected to date in New York State, which does in fact have walnut trees, Snover-Clift points out that the disease can take ten years to manifest, so it is possible that it’s already present but undetected.
So what does this all mean for those of us that work with wood? Is it panic time, will buyers start making a run on walnut? Rogers, for his part, isn’t worried—and that’s a good thing, as he sells wood for a living. (Rogers is Marketing Director at lumber supplier J. Gibson McIlvain.)
“[TCD] hasn’t been an issue with any of our suppliers,” Rogers says. “Plus we’re talking about walnut, which is already a high-defect species. Because it’s such a gnarly tree, walnut doesn’t deliver as high of a yield per log as, say, maple or oak, so it’s already expensive. It’s premium enough that as long as that demand stays where it is, price will always be the controller.”
The bottom line is, it’s hard for us to gauge what the impact is without being able to study hard numbers, which are not currently available, at least not in a place that we can find and access. We know that there have been walnut “die-offs” associated with the Walnut Twig Beetle and TCD in the past twenty years in the aforementioned western states and Tennessee, but without seeing percentages over time versus the total amount of trees, it’s tough to draw conclusions or make forecasts.
If TCD does start to make a numerical impact on the supply of black walnut, perhaps that would be Mother Nature telling woodworkers to switch to something else. Interestingly enough Arizona walnut, a/k/a Juglans Major, is completely immune to TCD, according to Ohio State University’s College of Food, Agricultural and Environmental Sciences. Unfortunately, those 50-foot trees are not the 100-foot black walnut, a/k/a Juglans Nigra, that we use for timber (though it’s just as pretty, as you can see below).
Sadly, the type of walnut most susceptible to TCD is in fact Juglans Nigra, according to the University of Arkansas’ Division of Agriculture. So we’ll have to hope for the best. As OSU points out, “There are no known effective treatments for trees affected by TCD. As a result, management efforts focus on disease prevention and sanitation.”
http://www.core77.com/posts/53089/Bug-Borne-Tree-Disease-Affecting-Black-Walnut-is-Spreading-from-West-Coast-to-East-Coast-of-America