Pam and I ambled around the Arboretum for our Easter 2023 outing.

Click Me for “Finger Lakes Memories” my online gallery.

All photography using the IPhone 14 ProMax triple camera, raw format, edited on the phone.

Betula papyrifera, common names Paper Birch, (American) White Birch, Canoe Birch, is a short-lived species of birch native to northern North America. Paper birch is named for the tree’s thin white bark, which often peels in paper like layers from the trunk. Paper birch is often one of the first species to colonize a burned area within the northern latitudes and is an important species for moose browsing. The primary commercial uses for paper birch wood are boltwood and sawlogs, while secondary products include firewood and pulpwood. It is the provincial tree of Saskatchewan and the state tree of New Hampshire.

As you can see in the following photoghraph, Betula papyrifera is a medium-sized deciduous tree typically reaching 20 meters (66 feet) tall, and exceptionally to 40 m (130 ft) with a trunk up to 75 centimeters (30 inches) in diameter. Within forests, it often grows with a single trunk but when grown as a landscape tree it may develop multiple trunks or branch close to the ground.

Paper birch is a typically short-lived species. It handles heat and humidity poorly and may live only 30 years in zones six and up, while trees in colder-climate regions can grow for more than 100 years. Betula papyrifera will grow in many soil types, from steep rocky outcrops to flat muskegs of the boreal forest. Best growth occurs in deeper, well drained to dry soils, depending on the location.

White Birch is a pioneer species, meaning it is often one of the first trees to grow in an area after other trees are removed by some sort of disturbance. Typical disturbances colonized by paper birch are wildfire, avalanche, or windthrow areas where the wind has blown down all trees. When it grows in these pioneer, or early successional, woodlands, it often forms stands of trees where it is the only species, a feature emulated in this Cornell Botanical Garden planting. Paper Birch is considered well adapted to fires because it recovers quickly by means of reseeding the area or regrowth from the burned tree. The lightweight seeds are easily carried by the wind to burned areas, where they quickly germinate and grow into new trees. Paper birch is adapted to ecosystems where fires occur every 50 to 150 years for example, it is frequently an early invader after fire in black spruce boreal forests. As paper birch is a pioneer species, finding it within mature or climax forests is rare because it will be overcome by trees that are more shade tolerant as secondary succession progresses.

For example, in Alaskan boreal forests, a paper birch stand 20 years after a fire may have 3,000–6,000 trees per acre (7,400–14,800/ha), but after 60 to 90 years, the number of trees will decrease to 500–800 trees per acre (1,200–2,000/ha) as spruce replaces the birch. After approximately 75 years, the birch will start dying and by 125 years, most paper birch will have disappeared unless another fire burns the area.

Paper birch trees themselves have varied reactions to wildfire. A group, or stand, of paper birch is not particularly flammable. The canopy often has a high moisture content, the understory is often lush green. As such, conifer crown fires often stop once they reach a stand of paper birch or become slower-moving ground fires. Since these stands are fire-resistant, they may become seed trees to reseed the area around them that was burned. However, in dry periods, paper birch is flammable and will burn rapidly. As the bark is flammable, it often will burn and may girdle the tree.

These metal tags are excellent signposts hanging from the branches on coated wire. Paper birch is a typically short-lived species. It handles heat and humidity poorly and may live only 30 years in zones six and up, while trees in colder-climate regions can grow for more than 100 years. Betula papyrifera will grow in many soil types, from steep rocky outcrops to flat muskegs of the boreal forest. Best growth occurs in deeper, well drained to dry soils, depending on the location.

In older trees, the bark is white, commonly brightly so, flaking in fine horizontal strips to reveal a pinkish or salmon-colored inner bark. It often has small black marks and scars. In individuals younger than five years, the bark appears a brown-red color with white lenticels, making the tree much harder to distinguish from other birches. The bark is highly weather-resistant. It has a high oil content; this gives it its waterproof and weather-resistant characteristics. Often, the wood of a downed paper birch will rot away, leaving the hollow bark intact.

Birch bark is a winter staple food for moose. The nutritional quality is poor because of the large quantities of lignin, which makes digestion difficult, but is important to wintering moose because of its sheer abundance. Moose prefer paper birch over aspen, alder, and balsam poplar, but they prefer willow (Salix spp.) over birch and the other species listed. Although moose consume large amounts of paper birch in the winter, if they were to eat only paper birch, they may starve.

Although white-tailed deer consider birch a “secondary-choice food,” it is an important dietary component. In Minnesota, white-tailed deer eat considerable amounts of paper birch leaves in the fall. Snowshoe hares browse paper birch seedlings, and grouse eat the buds.

Porcupines and beavers feed on the inner bark. The seeds of paper birch are an important part of the diet of many birds and small mammals, including chickadees, redpolls, voles, and ruffed grouse. Yellow bellied sapsuckers drill holes in the bark of paper birch to get at the sap; this is one of their favorite trees for feeding on.
As a species, Birches are commonly cultivated as fast-growing, graceful trees with ornamental bark.

The wood of Betula pendulas Roth. Is light and an excellent thermal insulator, so is used for the inside of saunas in Finland. The wood of Betula alleghaniensis is use for furniture, paneling, and plywood in North America.

Birch sap, collected in spring when it pours from the tree, can be used to make beer. Various species have been used medicinally, and Betula lenta was used as a source of oil of wintergreen, or methyl salicylate; American Indians used it to treat many ailments. Betulinic acid from the bark is reported to trigger cell death in melanomas in culture.

The bark of B papyrifera Marsh. Is waterproof and used for birch-bark canoes by American Indians, as well as for roofing in some parts of the world. Several species were used as paper, including Betula utilis, which has been found in the form of 1800-year-old Buddhist manuscripts in Afghanistan.

References:

“White Birch” Wikipedia

“Betula” from “The Botanical Garden I: Trees and Shrubs,” By Roger Phillips and Martyn Rix, Firefly Books, 2002 p123

Copyright 2023 Michael Stephen Wills All Rights Reserved