There was a smallish American beech in the woods not far from the second home my family lived at in Connecticut. It was not a loner, as in many places in the Southern New England Forest, beech were a fairly prominent tree there. This one, though, stood atop a rise that marked sort of a second, smaller peak of the hill we lived on. Their were two houses up there mostly surrounded by woods, making it a pretty good place for an outdoor-inclined child to do a hefty chunk of their growing up. That little beech on the second peak was big enough and just branched well enough to be a great climbing tree, and I hasten to make a guess at how many hours I spent off the ground in that tree. When the canopy was off it made an even better viewing position from the top of that already prominent rise, looking down a fairly significant and steep hill. I watched deer, foxes, coyotes, and even- only once -a fisher from that tree. I haven't seen it in a long while though, and I wonder how it's doing. I wonder because American beech in Connecticut are, on the whole, not doing so hot.
In 2012, a biologist named John Pogacnik working for Lake Metroparks discovered sick beech trees in a grove overlooking the Grand River in Lake County, Ohio. At the time, there wasn't a clear cut answer as to what was damaging these trees, but they were beginning to get sickly ,striated leaves, and it was evident that something was quite wrong. The disease would become known simply as beech leaf disease, and in time was tied to a nematode worm species: Litylenchus crenatae mccannii. Whether the nematode alone is responsible or if some bacteria is a nasty collaborator is yet unknown, but what is known is that the disease is more than just an inconvenience. BLD is proving to be especially deadly to younger beeches, which when infected seem destined to die in about five years time. BLD has since spread to 13 US states and Ontario, with detection in Connecticut occurring in 2019. It has since spread to every county, and it is rare now- in my experience, at least -to see a beech not affected by the disease.
Fagus grandifolia is a fixture of the eastern forests; "large-leafed beech" in Latin. You've probably seen one that someone scratched their name into. I don't at all condone this, it's a rude thing to do to a tree. This is done to a lot with beech because they do make a notably good canvas for such things, with their smooth, even, grey bark. American beech have lovely, dark green, almond shaped leaves with parallel side veins that each end in a slight point. Beeches are also notable for marcescence, or keeping some or all of their leaves through winter until they bud out. These dry, dull yellow leaves add color to an otherwise grey and white winter landscape in the northeast. They also whisper and shake in a breeze, and to me, a New England forest would feel very different were it not for that sound as a winter storm closes in and the wind kicks up. It would be really hard, as a whole, to picture these woods without beech. We've been through the loss of iconic trees in the East before, though... perhaps none more iconic than the American chestnut.
I walked a scrubby low area between hilltops in the Taconics not long ago with my friend Bruce, and we passed hundreds of little saplings with long, dark green, spike-edged leaves. Most of these were less than an inch in diameter and surrounded decrepit looking, dead small trees. These are what's left of a species now widely considered to be functionally extinct, stump sprouts from a still living root system trying desperately to regain a hold. It can't though, not yet at least. And that's a shame, because these were once a dominant and massive tree of the Eastern forests. Many old houses in New England have American chestnut in their construction, as it was a highly favored lumber for it's rot resistance and strength. Old film photographs depicting whole families standing in front of massive Castanea dentata harken to modern day photos of the redwoods or sequoia, and few trees standing today East of the Mississippi come close to the magnitude of those monsters, especially deciduous trees. At the moment the idea of seeing a truly giant American chestnut is a dream, and that's all because of a fungus imported by accident and rapidly spread through a population of trees that lacked immunity to it. There are folks trying to realize that dream, even though for many the understanding that this won't occur in time for them to actually see it is abundantly clear.
Jack Swatt and Dr. David Bingham explained to me how I could microwave-roast a chestnut as we stood at the base of 10-29, the tallest, fullest, best looking tree on Dr. Bingham's property in central CT. "Take a very sharp knife, put it on the flat side so it doesn't roll, punch it in so it makes a little x. As it's cooking the steam bursts the rest", Dr. Bingham suggested. In my hand was a nut produced by tree 10-29. It was a beautiful, lustrous thing with that stereotypical deep color. This tree and the others in Bingham's orchard are part of the American Chestnut Foundation's backcrossing program. The idea is to produce a tree that is as close to American chestnut as possible, but carries blight resistance from genetic crossing with Chinese chestnut. The chestnut in my hand wasn't quite as small as that of a pure American, and the leaves on the tree weren't as large or as toothed as as pure American. But it sure wasn't like a pure Chinese chestnut either, and though the cankers from blight were visible in various spots on the tree's trunk it was still a beauty. Bingham referred to and gestured at traits of the tree I was yet unfamiliar with. "It certainly has the very typical American bark, and it's branching like an American tree". Backcrossing, unlike pure hybridization, is intended to isolate one desired trait from a donor parent while crossing the offspring with a recurrent parent whose whole genetic background is preferable. In this case, preferred background is that of the American chestnut- traits like nut size, leaf size and shape, bark, branching, and growth -nd the preferred trait from the donor parent is the blight resistance of the Chinese chestnut. The end result won't exactly be the same as what was lost to blight, but the goal is to get the closest tree possible. That's a common theme in species conservation.... something as close as possible, genetically and physiologically, is a lot better than nothing.
The first nuts David Bingham planted in his orchard came from one Connecticut tree. "The mother tree" was an American chestnut he found while clearing a hilltop on a family property. It was just a sprout then, but Bingham cared for that tree by packing mud onto blighted spots and wrapping it with plastic. The native fungi and viruses in the mud help the tree fight the Cryphonectria parasitica, the blight fungus. If not taken care of, or if the tree shows no resistance, the fungus essentially girdles the trunk of the tree, killing it. The root system, unaffected by the fungus, can survive long after the main trunk dies It will keep putting up stump sprouts for decades. It was these that I saw on that hike in the Taconics. Under David's care, though, this sprout made it much longer than most. "It got big enough and started flowering," he told me. When it first produced nuts they were all flat, they were infertile nuts." If there are no other flowering chestnuts around to pollinate with, such is the result. The next year, with help from American Chestnut Foundation, the tree was pollinated. "We got about a hundred nuts off of it". So started the orchard; and that mother tree is still standing today too under Bingham's watchful eye. Rows of chestnut trees from the Mother Tree and various hybrid parents were planted in rows. They were then "inoculated", using bores to place a core with a virulent strain of blight in each tree. The trees that handled it best were kept, those that didn't were culled. It was those that made the grade that stood this day, here and there in what otherwise looked like a meadow. Bingham kept things to what the untrained I may think is a unruly state, but a naturalist sees as vital habitat for birds and pollinators.
The fungus that causes chestnut blight is Cryphonectria parasitica. Under a loop it isn't impressive... the fruiting bodies are tiny and dull orange. The impact of that fungus, though, was staggering. Most sources place arrival from Asia in the late 1800's. Ground zero was the Bronx Zoological Park. By the 1940's the blight spread to the entire population and in half a century a tree that made up about a quarter of the Eastern forests and a very high percentage of the mast crop (nuts) became a ghost of itself... still existing, sort of, but mostly as a reminder rather than a functioning species. Because of it's lumber value, salvage logging took place and may have worsened the odds for the iconic species. Now it's up to a handful of dedicated individuals to try to bring it back. Like many conservationists, Jack Swatt and David Bingham are driven by an appreciation for nature and for a species, using there time voluntarily to try to improve their world. Swatt learned about the American chestnut during his college years, joined the American Chestnut Foundation later on but wasn't very active right away. He'd been very active with the fire department, but after developing psoriatic arthritis needed to find another way to devote time. "So I was out hiking in Naugatuck State Forest and found an American chestnut that had burrs at the top of it," he told me as he donned gloves to protect his hands from the spikes. "I started doing more volunteer work and monitoring those trees because I had more time on my hands, and I became more and more involved". Many of use who find a species or habitat in peril quickly find ourselves entrained in the mission to restore, protect, or preserve them. Swatt described it as "infectious" and I couldn't agree more.
"Burrs go right through every glove I try", he said, "so I wrap them with duct tape. They're really pretty bad!" I'd never seen chestnut burrs before, but Swatt told me there are more trees that produce them than even he had realized. In places where lots of cutting has been done- he described a spot where cutting was performed to manage for Ne England cottontail -the sprouts can grow better, and in a five to ten year period before succumbing to blight they get a chance to flower and produce nuts. They emphasized that finding a tree with a lot of burrs is often a sign it isn't doing well and may be close to the end. "When you're finding them with burrs it's often because they've been weakened and they know that they're on the way out" Bingham said, and Swatt added "If they're growing really healthy, they put their energy into growing." The interesting thing with trees, though, is that growing takes a while. 10 years is long as is, and that's a fraction of the time it will take to know if any of this is working. Neither of these men will be around long enough to see the fully realized result of their hours of labor. David Bingham is 85 years old, and already has plans for the orchard he knows will outlive him. The property will go to a land trust to continue its goals. "I'm glad I didn't know how long this would take when I started" he told me. "I certainly thought it was going to be solved in my lifetime." At one point, he gestured at me, "You're young enough to maybe find a solution." And maybe that's true, but it wouldn't be without standing on the backs of people that came earlier who were willing to try to solve a problem they couldn't be around long enough to see through. Restoring a forest takes more than a lifetime. There's something deeply admirable about people willing to work toward a goal that far out.
Alex Amendola's office could be described as eclectic, I suppose, but if you are paying enough attention you'd see an underlying theme runs through the scattered odds and ends: two Polyphemus moths pinned to a propped up log, a copperhead skin shed, various mineral specimens, old bottles lined on a shelf, and a few bonsai, along with maps, old signs, and posters pertaining to ecology and forestry. These were all evidences of a life spent tromping in the woodlands of southern New England. Amendola is a forester for CT DEEP, and he certainly loves trees... though his path to his current occupation was a bit circuitous. "I wanted to be a a marine biologist, but they gave us a test for what job would suit you best. My number one result was forest ecologist, and I was like 'I hate trees, why would I ever want to do that'". Amendola was going to The Sound School, a New Haven based maritime based high school. He went from conservation law to environmental law in college, then found his way to that test result and ended in forest ecology. Now much of his life revolves around trees and things that pertain to them. He's the president of the Bonsai Society of Greater New Haven. Managing the forests of south Central Connecticut provides his income. I ended up in his office because my brother worked with Alex as a seasonal, and learned through him that forestry is a lot more than just marking trees. Radio telemetry with spotted turtles, for example... "I was astonished by how many thousands of feet some of them would put on in one night or two nights. I did the calculations to someone of my body weight and it was like 75 miles in a day!" If I was looking to get a deeper perspective on what beech leaf disease would mean for the whole landscape and the wildlife it would seem I'd been directed to the right person. After he got his seasonal set up with some office work for the day, we hopped in his work truck which was really a relatably (to me at least) disheveled version of the inside of his office- scattered with the tools of the trade, random rocks, and other accoutrements -and headed towards a site he was managing for Eastern red cedar and bigtooth aspen. These species don't do well under the canopy of taller trees but are a valuable asset for a diverse forest, so this site had been cut to free up these trees and give them a real chance. A variety of species rely on Eastern red cedar, including Juniper hairstreak, a lovely little green butterfly. The female trees produce beautiful blue berries that attract cedar waxwings.
When we arrived and walked out, we were walking through a landscape that might look a mess to the untrained eye. Most hikers and outdoorsman have a somewhat specific sanitized idea of what a healthy forest looks like and this probably wouldn't fit it... a scattering of tall trees with limited midstory and near breast high understory surrounding them. But this did have variety now, and was lacking it before. I'd been there before it was cut in fact, and remember seeing the grove of cedar Alex was seeking to save, trapped between taller mature trees. What now existed was and would for a while be different from what surrounded it. The seed bank that lives in the soil had gotten sun and all of this low growth came up, a whole host of different species than what had been represented before. Variety is key to ecological success, especially in a state with lots of developed land and an abundance of busy roads. The more different habitats available within an are, the more diverse and healthy it is. From birds to bugs to mammals, all benefit from varied habitats in close proximity. It still looked unnatural though, because it had to be logged to achieve the goals. I wanted to know what the progression would look like."It'll grow up, and you'll get to what we call the 'density dependent mortality'; you start to lose the losers for one reason or another- maybe its genetics, maybe its abiotic factors, biotic factors, whatever. Then you get the pole stand, small sapling stand and they'll start to reach up where they can." Pole is a timber classification; not yet sawtimber, no longer a sapling. "At that point the decision comes to burn, or do TSI or timber stand improvement, essentially selecting our favorites and trying to help them out. That'll happen in 20 years for these cedars. By that point their physiology should be strong enough to compete. Essentially the next step here won't be for another 15, 20 years?" This active management is so important to maintaining these species because it mimics what either would naturally have occurred in terms of disturbances- stand leveling storms or big fires -that shaped the diversity of plants and wildlife on the landscape, or mimics the land management carried out for centuries by the indigenous peoples. Because habitat is now fragmented, there's no guarantee that such events will occur in time naturally to keep some of these native species around. In order to keep some of them from disappearing from the landscape we have to come in and cut or burn things down selectively. It may look messy, but it is oh so vital. In southern New England, old farmland and meadows are lost to forest progression, and with them will be species like the New England cottontail, smooth green snake, and indeed red cedar. "We want to have eight to ten percent of our forest in this early successional stage across all of Nehantic. Wind storms, fires... all of our forest is really predicated on that in Southern New England."
Beech fits into all of this. "They provide that mid story that is very important to some birds," Alex told me. Not every tree branches in the same way. Some form a single trunk with branches coming off That same characteristic that made them fun to climb when I was a kid is key for species whose feeding or nesting habits evolved around the presence of that tree and others with heavy branching further down their trunks. Beech also make large groves of trunks from one root system. What looks like a bunch of different trees is really just one organism. The smaller sprouts in these groves produce both understory and midstory as they grow, and under the shade of the larger trunks they remain a lasting example of that habitat. At least they did, until a new nematode came along. We stood under a grove of beech that was looking quite sickly discussing how that nematode works. "The damage was done inside the bud, then when it leafs out it's all screwed up. If you see the microscope footage, the nematodes just cause physical damage tunneling all through the cell walls". This damage produces shriveled, misshapen, striped leaves that can't execute the processes they're meant to. It'd be like if something went to town and did a bunch of physical damage to your stomach and prevented you from being able to take in nutrients. Many beeches try to refoliate, but they aren't very good at it. "They don't even look like beech leaves." Sycamore, by contrast, refoliate every season in response to anthracnose, dropping their leaves and re-growing a new healthy batch. We don't know why beech can't do the same yet. That means trouble for a landscape scale problem, and it's unclear if there will be a good way to solve it. "There are plenty of beneficial nematodes," says Amendola. "Spreading some sort of nematicide would be comparable to something like DDT". DDT, dichlorodiphenyltrichloroethane, is a synthetic insecticide commonly used to control mosquitoes. It had severe environmental impacts, most notably thinning the eggshells of raptors. Though banned many decades ago, DDT still shows up in FDA food tests and in all nearly all CDC human blood tests.
Beech leaf disease has spread very rapidly. The range of beech is over 800,000 square miles in the Eastern United States. Beech leaf disease has spread to about 160,000 square miles since 2012, so it's gotten to about one fifth of the distribution of the species in the country already. That's not including Eastern Canada, either. The tricky thing is, it was novel from the start. Research to understand the disease, what caused it, where it came from, and how it might be controlled has to be performed while the disease proliferates. Science takes time, and all the while, the disease is killing trees, damaging habitat, and creating thousands of dangerous snags that could fall and injure folks outdoors. Though there are obvious differences between chestnut blight and beech leaf disease, both are landscape scale problems. We have to hope that we could learn from the past and come out of this better than the chestnut blight, but we already blew it: the disease is here. That's the most dangerous step, and once that door is open its really, really hard to close. Alex drove me through Chatfield Hollow State Park, pointing out stands of birch that were so beaten down by the disease that they were already becoming a potential danger, not to mention opening up the brook to full summer sun and warming the water dramatically.
If you see a beech tree that seems to be resistant to the disease, note it's location and see if it holds out, because discovering just a few resistant trees could be vital to weathering this storm. Stay apprised of BLD and other tree diseases and invasive species through the Connecticut Agricultural Experiment Station at https://portal.ct.gov/caes. Generations down the road, there may still be big, healthy beech standing in our forests, and maybe even American chestnut. If there are, it'll only be because people like David Bingham, Jack Swatt, and Alex Amendola cared enough to see something through to their own end despite the knowledge that they'd never get to see the result.
Thank you to my Patrons; Erin, David, John, Elizabeth, Brandon, Christopher, Shawn, Mike, Sara, Franky, Geof, Luke, Noah, Justin, Sean, Tom, Mark, Jake, Chris, Oliver, oddity on Display, Sammy, and Cris & Jennifer, Hunter, Gordon, Thomas, Trevor, Eric, Evan, Javier, Ryan, Dar, Eric, Truman, and Collin for making Connecticut Fly Angler possible. If you want to support this blog, look for the Patreon link at the top of the right side-bar in web version.
No comments:
Post a Comment