In 2012, when I was on site full-time, I looked closer. This year, in contrast to before, squirrels were much in evidence, and although the spiny chestnut fruits were immune to penetration by jays, they were routinely breached by squirrels, though probably not to the benefit of the trees’ reproduction.
As in the previous two years, all four chestnut trees were laden with green fruits in early October. As before, soon after those fruits started to form, the ground under the trees was strewn with hundreds of aborted infertile duds. Red squirrels, Tamiasciurus hudsonicus, ignored them. Instead, they climbed into the trees and scrambled methodically from branch to branch, to snip off green unopened fruits that all dropped straight to the ground. These, however, all contained nearly ripe seeds.
A squirrel usually started at the tree each day at dawn and snipped off three to five fruits per minute, and then continued to work until it had dropped a hundred or more. It then left the tree and for the rest of the day perched on the ground or on a stump and eventually gathered the fruit up. One by one it chewed them open and ate the nuts. Additionally, it sometimes took a fruit in its mouth and clumsily carried it three or so meters to a perch to feed on it. Gray squirrels, Sciurus carolinensis, came also, but they never once snipped the fruits off to let them drop. Instead, they fed exclusively while remaining perched on the tree.
Together the two kinds of squirrels removed most of the hundreds of green fruits from the trees before the fruit had a chance to open, hence before any jay could have gathered a seed. I found no whole fruit that had been carried off into the surrounding woods, but the ground under and around the trees was littered with piles of chewed and empty burrs. Jays may have planted chestnuts in previous years, but the squirrels seemed poor candidates. The question was: Did either ever act as nut planters?
As mentioned already, I had seen the jays fly off with chestnut seeds in 2010 (and they may have been doing it in previous years), but whether or not they were helping the chestnut trees to reproduce is a separate question. Squirrels have an amazing ability to locate seeds by scent, and turkeys and mice that abound in the woods are also likely able and eager to eat any just-deposited nuts they might find. Any nut that does manage to make it to the seedling stage would probably be a small percentage of the total number of seeds that were dispersed, unless the seed dispersers do something that helps seed survival beyond what would happen from simply being dropped onto the ground. Those simply dropped onto the ground are likely to be more easily found and eaten as well as more vulnerable to drying out or freezing and not germinating. Possibly deep burial, and/or several seeds in the same place, may help to produce a seedling, because the seeds would be protected from both drying out and freezing and because a predator that goes by scent may overlook a seed after it has presumed to have mined the reward at the end of the scent “trail” that attracted it.
To find out if my chestnut seeds were indeed dispersed and had survived as well, I searched for seedlings, first in the immediate vicinity of the trees where nuts would have fallen or could have been scattered, and then at ever-greater distances. If a young chestnut tree was found in these woods, there could be no doubt about its origin, as well as the distance dispersed. American chestnuts were a convenient species for examining how far animal-dispersed seeds may be planted away from the parent’s home ground, because unlike almost all of the other local tree species, the seedlings retain their leaves into late October, after most other trees. This makes it easy to locate baby chestnut trees in the fall because their large saw-toothed, still green or yellow leaves show up brilliantly from afar against the then-prevailing brown carpet of the forest floor.
I found only two seedlings under or adjacent to the four chestnut trees, and so I did not have much hope of finding any in the woods. But I searched nevertheless. To my surprise, I soon found seedlings everywhere, and several of them were nearly a kilometer from the nearest chestnut tree. I do not know the total number of offspring these chestnuts had by then (in fall of 2013) growing in this forest, but I located 158 “plantings” of trees spread out over an area of about 200 acres (81 hectares). One hundred twenty of the plantings grew only single surviving trees. The rest were of two to twenty seedlings (or small trees) in a tight bunch in the same spot. The surviving seedlings and trees are of course the minimum numbers that were actually planted.
Who were the planters? If the nuts had been planted by red squirrels, they should have been close to the tree, since the squirrels are highly territorial and would not hide their food in others’ domains. They should also have been most commonly in groups of three, since these squirrels, when they did leave with chestnuts, always carried a whole fruit, which has up to three seeds in it. Unlike chipmunks, tree squirrels do not have cheek pouches for carrying multiple seeds. Blue jays routinely carried several chestnut seeds at once, and they flew far out of my sight with them. Since I found up to five at one spot at a great distance from the parent tree, one can infer that blue jays had been the responsible tree planters. Only the jays could account for plantings of more than three seeds at one spot. Chipmunks were also a possibility for nearby planted trees.
I wanted next to find out possible requirements of seed survival such as those that the caching by animals might provide. I had found that all seeds put on wet peat moss in a plastic bag in a refrigerator were dead the next spring. This time I put fifty into wet peat moss again in a plastic crisper which I left outside on the woodpile. Again, all fifty seeds were mushy and dead when I examined them right after snow melt. Fifty that I put (in ten piles of five) onto the ground (in maple woods) were missing by spring. Of one hundred buried two centimeters deep, seventy-six were missing, but of fifty buried ten centimeters only six were missing. I concluded that burial in the soil is necessary both to facilitate seed survival due to physical conditions and to avoid predation. Apparently the jays were doing several things right to bring the seeds to a good place where they could make a start.
Three seedlings that had started in the woods within 130 to 300 meters of their parents have already reached heights of three to five meters. They have reached sunlight and are shooting up at seventy centimeters per year. They are now well on their way to becoming trees, and they could not have come from anyplace else but the specific ones I had planted. The chestnuts may not have fallen far from the tree, but they had escaped the boundary of their parents. They had left “home” and the otherwise inevitable parent-offspring conflict for light, water, space, and soil nutrients. They were of variable ages, suggesting that American chestnuts do not, like the beeches and some oaks, have their October seed-bearing pulses separated by years without flowering and seeding, which serve as a time boundary that can help maintain the seed predators’ populations. Instead, they have tough, spiny fruit that serves the same purpose by being a physical boundary to easy access and predator overpopulation. They exclude birds until their seeds are ripe and ready for planting and may then be dispersed, provided enough seeds are available all at once to satiate the then-available takers.
The chestnut trees’ dependable annual seed crops, the timing of which would have been staggered over a latitudinal gradient, may have provided a reliable food resource to highly mobile birds, such as the now-extinct passenger pigeons. We will never know to what extent this formerly reliable food helped the pigeons to achieve their enormous population size, but the large numbers of them needed in any one colony in order to be stimulated to breed, as we’ll see a little later, would ultimately become the final cause of their extinction.
Thanks to the science and ethical commitment to species regeneration of the American Chestnut Foundation (which breeds blight-resistant trees), the chestnuts are coming back, just as the fish and game departments have returned the deer, the turkeys, and the moose. In my forest, where the chestnuts now grow, the turkeys have also returned. Both are multiplying. The forest is largely a mixture of American ash, yellow and white birches, red and sugar maples, American beeches, black cherries, and some white
pines, red spruces, and balsam firs. By planting the chestnuts, I breached an artificial boundary. Species are being readmitted to their ancestral home where they were part of a complex ecosystem. By planting four trees, I am helping the jays, and more, make it whole again.
Postscript
As this book was going to press, the New York Times asked me to write a short essay for its op-ed page. The Times had no specific topic to suggest, and I had none on hand, until I thought of the above-described Hail Mary shot-in-the-dark experience of planting four American chestnut seedlings thirty-two years ago. The off-the-cuff abstract, which appeared on December 21, 2013, generated a strong response from readers.
A main concern of readers was the source of my chestnuts. This had been a concern of mine even before writing this chapter. I had, among my innumerable crates and boxes of saved paper, by sheer luck found where I had written down that I had purchased the seedlings from the “Westford County Soil Conservation District. Cadillac Mountain, Michigan.” But I could not find this on Google, and so assumed it either no longer existed or had changed its name in the intervening decades. The American Chestnut Foundation was founded in 1983, the year after I had planted the trees from Michigan, and it began breeding for blight resistance in chestnuts in 1989. The ACF was unable to help me.
The op-ed readers reminded me, though, that knowing the source of my original stock is important, because some didn’t believe I had planted real American chestnuts, maybe because it sounded too good to be true. So, under a new stimulus, I made another search. Eventually I located an American Chestnut Council in Cadillac Mountain, Michigan, where a man named Tom Williams offered “American chestnut seedlings” for sale. I called the number (231-775-7681) and got the U.S. Department of Agriculture, and a long recorded message referred me to extension 3, which turned out to be none other than—the Westford County Soil Conservation at Cadillac Mountain! I had read on Wikipedia that the American Chestnut Council had located “a blight-free grove of American chestnut trees of approximately 0.33 acres (0.13 ha).”
“The” map of the original range of the American chestnut shows the chestnut tree only in the southeastern part of Michigan near Ann Arbor, not 190 miles northwest at Cadillac Mountain by Lake Michigan. That map also shows numerous other seemingly relict isolated populations. Most of these populations became extinct when the blight swept over the country. However, could some have survived because they were resistant to it, or were they saved simply because of their isolation?
It was the day before Christmas—and the very last day to include edits in my book. But this one was important, so I left a message on the answering machine at the USDA number I had called, and got an email response from Max Yancho, who identified himself as “Wexford Conservation District forester” of the “Wexford and Missaukee Conservation Districts.” I had been misled for years in my search for the origin of my chestnuts by misreading an x for an s! Solving this riddle was the best Christmas present I could have imagined. But it got better.
Yancho wrote: “I received your message this morning about your chestnut trees. I had a hard time hearing all of your message and I hope that I can reach you via this email, but the chestnuts which you planted are very likely from the American Chestnut Council based here in Cadillac. The ACC sends chestnuts all over the United States, and uses natural seed stock collected from native groves here in Michigan. I was able to read your op-ed piece online, and I hope this puts your mind at ease. It sounds like you have been very successful in re-introducing the chestnut back into the Maine forest.”
Of Trees, Rocks, a Bear, and a Home
The mountain pushed us off her knees.
And now her lap is full of trees.
—Robert Frost, “The Birthplace”
MAKING A HOME IS “TAKING ROOT” IN A PLACE. IT IS GROWING enough permanence to encompass life spans and to leave physical traces, such as those in the arrangements of rocks or the planting of trees. In pioneer days in the American Midwest, in order to claim land, settlers had to plant an apple orchard, which proved their seriousness about making a home there. This was the setting for the American legend of Jonathan Chapman, now known as “Johnny Appleseed.” A New England native, Chapman traveled nearly sixty-five hundred kilometers throughout the Midwest planting and tending nurseries of apple trees. He often went barefoot, was known for his kindliness and sensitivity to animals, and, unlike many other white settlers, liked and got along with the Native Americans.
Chapman was born in Leominster, Massachusetts, in 1774. The young Johnny would have grown up on or near farms being built by clearing the land of trees, gathering the rocks into walls, and planting apple trees. Most of those farms cleared from the northern New England woods were abandoned in 1816 after “The Year Without Summer,” following the April 5–15, 1815, eruptions of the Tambora volcano in Indonesia. Until the dust settled, it caused violent weather the world over. Frosts killed New England crops in May of that year and produced snowstorms in June. A bitter famine winter of 1817 followed, and people left the rocky New England slopes to settle in the American Midwest, then called the “Northwest Territory.” The Krakatoa eruption of August 26–27, 1883 (also in Indonesia), was the second-largest eruption in historic times and caused a temporary drop in global temperatures that helped effect a second wave of local land abandonment and westward migration.
There is now an expanse of unbroken (though often heavily lumbered) forest in northern New England where there used to be fields and pastures. The place names in western Maine in Perkins township are Chandler Hill, Kinney’s Head, Gammon Ridge, Gleason Mountain, Potter Hill, Wilder Hill, Lakin Hill, Holt Hill, Hedgehog Hill, my own York (or Adams) Hill, Houghton Ledges, Parlin Brook, Bowley Brook. All except Hedgehog (no hedgehogs exist in America; the name refers to the local porcupine) are named after those who made their homes here long ago. The names of the towns are more fanciful, possibly reflecting less the homes of origin than wished-for Shangri-Las of the original settlers. Within a drive of an hour or two, one can visit Naples, Moscow, Hanover, Berlin, Poland, Norway, Denmark, Sweden, Paris, Stockholm, Mexico, China, and Peru.
Few icons of the past evoke romantic nostalgia like the old stone walls and stone-lined cellar holes that one now finds scattered about deep in the woods. Sixty years ago, when my family settled on an old farm in Maine called “The Old Dennyson Place,” it was not far from becoming one of those many memories. There was then not a farm without at least a remnant of “the old apple orchard,” where on crisp autumn days men and boys flushed grouse and saw porcupines, the fresh tracks of deer, and often a pile or two of bear dung, which looks like applesauce made from whole apples, seeds and all. Sometimes deep in the woods we would see trunks of fallen apple trees moldering into the ground, usually near some rock-lined cellar hole from which trees grew. These favorite places of boys and other wild animals are almost gone now, and you must look closely to see clues of the former homesteads. But rocks and trees still provide reminders of past homes.
The original settlers and their dreams are past, but there is permanence in stone. Next to my cabin is the crumbling cellar hole of the original York and Adams family farmhouse. Most of the rocks of their farmhouse foundations had collapsed into a pitlike depression where a hefty white birch tree, an American ash, a red spruce, and a maple sugar tree had grown. I cleared the trees and brush and chopped, ripped, and tore out a network of roots before I could start resetting rocks. Like a raven in springtime coming back to a ledge and placing a stick or two where it might build a nest if it didn’t slide off, I was at that time playing.
During the clearing and digging out, among the submerged granite blocks that had been part of the foundations for two barns I found rusted remains of hay scythes, horseshoes, ax heads, hubs of carriage wheels, pottery shards with pink and blue floral designs, railings from a horse-drawn carriage, plow blades, odd metal rings, lengths of chain, innumerable square nails, hinges, a blue enameled tin cup, and charcoal. Generations had come a
nd gone and the records of their lives have blurred. But there were stories here, and I thought, “If only trees could talk.” Silent for a long time, an apple tree eventually did “talk.”
The apple tree that had first caught my eye around 1980 because of its large circumference was almost dead. It had a short but hugely thick trunk with two tree-size broken stubs that branched off about one meter from the ground. Most of the tree had broken apart and had long rotted into the ground, but one of the broken trunks still had a thin live sucker shooting straight up in a losing fight to reach sunlight through a rapidly closing canopy of young ash, maple, and white pine trees. I didn’t give this tree much thought then while thinning out a future sugar bush. However, thirty years later, when the tree’s one remaining live shoot had died, I wondered how long the tree had lived. Henry Braun, a poet from a kilometer or two on the other side of this hill farm, had written, “It isn’t far in Maine to the end of the past.” Just how far is it? I wondered. Thinking that the old tree might give clues, I chain-sawed the remains down to take a section of still-solid wood and count its growth rings. After sanding and polishing the rich brown-red wood, I counted on average twenty-five growth rings per inch in the outer wood, although the growth deeper in before the tree’s decline had been more rapid. There I counted thirteen rings per inch. I calculated that the tree must have started to grow near 1790. Johnny Appleseed was around twenty years old then. George Washington had just taken office as our first president. It was almost a decade old when John Adams, our second president and one of the recognized most influential founders of the United States, was finishing his term. It was a vigorous young tree when his son, John Quincy Adams, was the sixth president.
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