The Giving Tree

For more than a thousand years in eastern North America, anyone who wanted to build a house or replace a roof, or maybe just needed a few storage bins, a canoe, and a snow shovel, knew where to shop. In what is now southeastern Canada and northeastern US, the American elm (Ulmus americana) was a veritable Home Depot for many First Nations peoples.

Although elms are still present in our forests, Dutch elm disease, which has the appropriate acronym “DED,” now kills them before they can reach maturity. This fungal pathogen from Asia appeared in Western Europe shortly after the first World War, and by 1930 had migrated to the US. It took a few years to discover Canada, reaching there in 1946. Disease spores are spread by two bark beetles, one native and one introduced.

As the DED fungus spreads, it clogs xylem tubes that bring water and nutrients up to the leaves. Where elms grow crowded together, as was the case in many towns and cities up until the 1970s, DED also spreads through root grafts. This is the way in which whole elm-lined streets became denuded in a matter of a few years. A few trees show a degree of natural resistance, but all native elms succumb eventually.

Before the arrival of DED, these fast-growing trees attained their largest proportions in the rich flood plains of eastern North America, where they grew to 100 feet tall, their trunks reportedly more than nine feet across. Elms tend to shed their lower branches early in life and typically have upright, vase-like forms.
This expanse of knot-free bark on the lower trunks of great elms was ideal for the roofs and walls of longhouses back in the day. Prodigious sheets of elm bark were peeled in spring and early summer and then anchored flat to bake in the sun. Once dry, a sheet of elm bark is the equivalent of plywood.

Covering a longhouse was an impressive feat, as some of them are known to have been over 150 feet long. Elm was also used to enclose smaller dwellings and outbuildings. In fact, elm was perfect for making items as diverse as canoes, trays, snow shovels, ladles, grain scoops, baskets, and containers of all sizes.

Fresh elm bark has the feel of thick, wet leather, and may be worked in much the same fashion. It can be bent, sewn, clamped, cut, or tied into an array of useful articles. Once dry, the roof panels, utensils, containers, and other useful items become rock-hard and will hold their intended shape, even if exposed to moisture again.

The Haudenosaunee (Iroquois) in particular made extensive use of elm “plywood.” After sheets of bark were laid out flat, holes were easily punched with something sharp like a hawthorn, or drilled using a bow-drill, along the edges while the bark was still pliable. In a few days the sections were ready to lash to the log framework of a longhouse, which might be home to dozens of families.

Being consummate agronomists, the Haudenosaunee stored massive amounts of grain in each of their towns. European colonizers such as Jacques-René de Denonville, Governor General of New France (1685-89), wrote of their amazement at finding tens of thousands of bushels of corn on hand in giant elm-bark bins and cribs in the Haudenosaunee villages they gleefully burned to the ground.

I’m told the Haudenosaunee made primarily elm-bark canoes because paper-birch trees were not as abundant in most of their territory as it was to the north. Being heavier than birch-bark vessels, elm canoes were not portaged, but used locally for travel on lakes and rivers.

Between late spring and mid-summer, elm bark can be removed with no more effort than peeling a banana. To be sure, that “peel” is heavier, but it lifts off the tree trunk with ease. Elm bark shrinks as it dries, but unlike the “skin” of many other species, doesn’t readily split. Not only is fresh elm bark easy to work with, it is fun to the point of being addictive. Ever since an Abenaki friend taught me to make elm rattles, spoons, and baskets over thirty years ago, I try to locate a small elm or even a branch to peel every spring.

Small to mid-size elms can be found throughout their native range from Nova Scotia south to northern Florida. In higher elevations, where soil type rather than climate often limits where elms can grow, isolated stands of elms may see less-frequent DED infestation cycles. These stands often grow for decades, becoming fairly large before they perish.

Some of North America’s largest old elms can be found in places such as New York City’s Central Park and on the campus of Penn State University. These old-timers exist thanks to a regimen of systemic fungicide injections and insecticidal sprays. In fact, Penn State clears its campus for a few days each year so helicopters can spray its elms.

Chinese and Siberian elms are very resistant to DED, but neither comes close in size or shape to American elms. Since 1983, the Elm Research Institute in Keene, New Hampshire, has promoted “American Liberty Elms,” some of which have resistance to DED, although they are not immune. Hybrids between Chinese and American elms have fair resistance, but they still can’t fill the shoes, as it were, of Ulmus americana.

Although it may be a long way off, someday we’ll again have massive elms like those whose bark once covered longhouses. It’s a sight I’d love to see.

By Paul Hetzler

Paul Hetzler is a former Cornell Extension educator, and he also writes books! His most recent, and one you must have for your island library -Head of the Class: Smart as Slime Mold: Nature's Funny Bone Revealed is available on Amazon.com and Amazon.ca.

Marie-Anne Erki

Marie-Anne Erki is TI Life's  illustrator and accomplished artist. She is also Professor Emeritus of Civil Engineering at Canada's Royal Military College where she taught for twenty years. She has already produced individual illustrations for Patrick Metcalf's The Witch of Wellesley Island (see STORIES+) and illustrated many of Paul Hetlzer's past articles.

Editor's Note:  OK. Paul, we are about to head in the TI Life winter season, and I am hoping you are not going to stop finding these interesting (aka amazing) nature stories. Who says learning is not fun?

Posted in: Volume 17, Issue 10, October 2022, Nature