Winterbark; difficult and time consuming to harvest, painstakingly using a wooden splint to meticulously separate the outer bark from the cambium.
Summerbark;
It is far easier to harvest birchbark once the sap begins to flow -as indicated by the buds starting to leaf out. Sometimes the bark even "pops" off the tree once you have done the circular and longintudinal cuts.
Bark can be harvested from a standing tree or after falling a tree, which risks bruising, splits and delamination from impact. Some people lay a bed of spruce boughs and small trees to fell the log onto.
There are several methods to harvest from a standing tree, leaving the tree living as there is a corky cambium layer remains on the tree when you remove the outer bark.
Use a ladder. Hold the bark from the top using a spring clamp and rope, so the bark can be lowered to the ground gently.
Someone (unnamed) is known to screw a series of lagbolts into the tree to climb up. I consider this dangerous, unless you are part monkey ie. have a tail for extra hold.
Or top rope for safety.
At one time there was a list of birchbark canoe building resources posted on the WCHA website. I couldn't locate it, so attach my compilation here. (Some of the hyperlinks may be outdated)
Birch Bark Canoe Resources
Bibliography
Adney, Edwin Tappan & Howard I. Chappell., The Bark Canoes and Skin Boats of North America. 1983
Behne, C. Ted (ed). The Travel Journals of Tappan Adney:1887-1890. 2010
Dina, James. Voyage of the Ant. 1989.
Evans, Doug. Noah’s Last Canoe: The Lost Art of Cree Birch Bark Canoe Building. 2008.
Gidmark, David. Birchbark Canoe; Living Among the Algonquin. 1997
Gidmark, David. Building a Birchbark Canoe The Algonquin Wabanaki Tciman. 1994
Gidmark, David. The Algonquin Birchbark Canoe. 1988
Gidmark, David. Birchbark Canoe: The Story of an Apprenticeship With the Indians. 1989
Gidmark, David. The Indian Crafts of William & Mary Commanda. 1980
Goode, F. W. Beaver Bark Canoes: The Art & Works of Ferdy Goode, 2010
Guy, Camil. The Weymontaching Birchbark Canoe (Anthropological Papers No. 20, National Museum of Canada), 1974.
Russell & Ned Jalbert “Mocotaugan: The Story and Art of the Crooked Knife”
Jennings,John. Bark Canoes; The Art & Obsession of Tappan Adney. 2004.
Jennings, John. The Canoe: A Living Tradition. 2002.
Jennings, John, Bruce W. Hodgins, and Doreen Small, (eds.) The Canoe in Canadian Cultures. 1999.
Kent, Timothy J. Birchbark Canoes of the Fur Trade (vols. 1 & 2). 1997.
Kent, Timothy J. Paddling Across the Peninsula: An Important Cross-Michigan Canoe Route During the French Regime. 2003.
McPhee, John. The Survival of the Birchbark Canoe, 1999
Raffan, James & Bert Horwood (eds.), Canexus: The Canoe in Canadian Culture. 1988.
Ritzenthaler, Robert E. Building a Chippewa Indian Birchbark Canoe. Milwaukee Public Museum. 1984.
Roberts, Kenneth G. & Philip Shackleton. The Canoe: A History of the Craft from Panama to the Arctic. 1983.
Rossman, William. Builder of Birch Bark Canoes. Grand Rapids Herald Review (reprinted, Minnesota Historical Society). 1969.
Schneider, Richard G. Building a Birch Bark Canoe. 2000
Wilson, Ian & Sally Wilson. Wilderness Journey; Reliving the Adventures of Canada’s Voyageurs. 2000.
Streaming Video
Aaron York building a canoe at the Lake Champlain Museum;
Cesar’s Bark Canoe (National Film Board of Canada);
http://www.nfb.ca/film/cesars_bark_canoe
“Earl’s Canoe” Documentary Educational Resources;
Dave Brown: How to Build a Bark Canoe, Fort William, Thunder Bay;
Halin, Birchbark Canoe (1st of 6 parts);
Bill Hafeman with Charles Kuralt (CBS);
Ishpeming Canoes (time lapse build);
https://www.youtube.com/watch?v=td8h5g33ujE
Building a Birch Bark Canoe and Preserving the Ojibwe Language;
https://www.youtube.com/watch?v=YrrwCj1CdJ4
Moses David Bridgeman - Passamaquoddy Canoe;
https://vimeo.com/58055134 https://vimeo.com/58055134
How Indians Build a Canoe (1946);
https://www.youtube.com/watch?v=enMSwz5BWGo
Grant Goltz documentary on building a Birchbark Canoe (57 minutes);
https://www.youtube.com/watch?time_continue=2258&v=bPvbKgxN1c4
Ray Mears & Pinock Smith, BBC World of Survival; (1st of 7 part series);
https://www.youtube.com/watch?v=ZqmHqrHr8xg
How Indians Build Canoes (1946);
https://www.youtube.com/watch?v=enMSwz5BWGo
Voyages of Rediscovery (time lapse);
https://www.youtube.com/watch?v=4Lp9J9jV29g
Becky Mason & Reid McLaughlin, canoe ballet in birchbarks made by Ferdy Goode and Steve Cayard;
https://www.youtube.com/watch?v=fZ9MV0drMbA
The Old Canoe (music and historical photos);
https://www.youtube.com/watch?v=lz6j_KXL9pM
Other Web Resources
Canoe from the Penobscot River An Article from
American Neptune 1948;
http://www.wcha.org/literature/penobscot/