It wasn't really quite that neat. In the Northeast, for example, Maine represents the southernmost range in which the white birch grows to sufficient size to produce canoe skins. Nice sheets of canoe bark were a valuable trade item, exported by Indians from Maine and Quebec to nearby states, and so some bark canoe building did occur somewhat south of Maine. But dugouts were much more widely used than bark canoes throughout most of New England, including southwestern Maine.
Let's start in prehistory. Although the date for the invention of the birchbark canoe is in dispute (some say it might have been just prior to European contact; others place it some 500 or 600 years earlier), it is clear that dugouts were widely used throughout coastal Maine prior to that, including areas that would later become birchbark country. As far back as the Early Archaic (10,000 to 8,000 BP), tools such as gouges and whetstones were in use -- tools that may well have been used to hollow tree trunks for canoes. By the Moorehead phase (6,000 to 4,000 BP) of the Middle Archaic, there is clearer evidence. Finds of numerous swordfish bills and quantities of cod and seal bones in archaeologically excavated coastal settlement sites are sure indicators that the people were venturing away from the shore, and since the bark canoe certainly did not exist at that time, the dugout is the only craft in which they could have done so.
The earliest dugout of which I've read from the region we're discussing (New England through the U.S. midwest, and adjacent Canadian provinces) is a 2,000-year old example discovered in Lake Mary, Kenosha County, Wisconsin.
In 1634, the poet William Wood, who produced the first detailed map of southern New England, described dugout building in Massachusetts, writing that they were not greater than 2' wide and about 20' long. An eastern white pine dugout discovered in Weymouth, Massachusetts in 1965 (image at top of post) measured 11' x 2 ' 11" and has been dated to about 1500 A.D. -- i.e., before European contact. Three dugouts found in 2001 near Worcester, Massachusetts, date to the mid-1600s -- a time at which contact had occurred, but may not have yet significantly influenced the Nipmucs living some 75 miles west of Plymouth. For details on this find, which is an active achaeological project, see Project Mishoon.) A pine canoe found on Lake Ossipee, New Hampshire, and owned by the Museum of New Hampshire's History, has been dated to between 1430 and 1660.
In 1643, Roger Williams, the founder of Rhode Island, described the local dugout canoe, or mishoon:
Mishoon an Indian boat or Canow made of a Pine or Oake, or Chestnut-tree: I have scene a Native goe into the woods with his hatchet, carrying onely a Basket of Come with him, and stones to strike fire when he hadJeld his tree (being a chestnut) he made him a little House or shed of the bark of it, he puts fire andfollowes the burning of it with fire, in the midst of many places. his come he boyles and hath the Brooke by him, and sometimes Angles for a little fish; but so tree continues burning and hewing untill he bath within ten or twelve dayes (lying there at his worke alone) finished and (getting hands) ranched his Boater with which afterward tree ventures out toflsh in the Ocean.... Some of lthe canoesl will not well carry above three or foure: but some of them twenty, thirty, forty men.... Their owne reason hath taught them, to pull of a Coat or two and set it up on a small pole, with which they will saile before a wind ten, or twenty mile.... It is wonderfull to see how they will Denture in those Canoes, and how (being oft overset as I have my selfe been with them) they will swim a mile, yea two or more safe to Land I having been necessitated to passe waters diverse times with them, it hath pleased God to make them many times the instruments of my preservation. and when sometimes In great danger I have questioned safety, they have said to me: Feare not, if we be overset I will carry you safe to Land.... (this quote taken in full from Rhode Island Sea Grant, here).In a series of posts (titled, confusingly, Michigan's Whitewood Canoes, Whitewood Dugout Canoes VI, and Whitewood Canoes VII) on his inactive but still present eponymous blog, Jim Woodruff explains that southern Michigan was south of the range for canoe birch, but within the northern limit of the range of the tuliptree or yellow poplar, known to settlers as whitewood. Early settlers found very large whitewood dugouts in wide use there by the local Pottawatomie people, being used even for lengthy voyages on Lake Michigan. In contrast, the Chippewas or Ojibwas in northern Michigan were bark canoe builders, but they too were known to build and use dugouts. A 30-footer was acquired by a Euro-American from a Chippewa in 1837 and, in 1864, a large number of dugouts were built and used for a Chippewa migration. Whether this was an expedient due to pressure from Euro-American settlers, or an established element of their material culture, is not clear from Woodruff's post. (In the migration incident cited, the canoes were built somewhat inland, and hauled by wagon to the nearest waterway -- obviously not part of the indigenous technology.)
Woodruff goes on to argue that the dugouts used in Michigan were not as cumbersome as is often supposed -- he cites evidence that they were at least sometimes portaged. (Tuliptree is a particularly lightweight wood, and dugouts can be hewn to sufficient thinness so that they aren't outside the range of what even today's canoeists might consider portagable.) And he notes the one great advantage of the dugout: its toughness. One can drag a dugout over rocks and snags that would hole a birchbark canoe.
Finally, a paper by Edward S. Rogers ("The Dugout Canoe in Ontario", American Antiquity, Vol. 30, #4, April 1965) describes 18 dugouts in that province, ranging from 10' to 20'3", and built of basswood, pine, and possibly poplar. The paper found instances of both native and European construction of dugouts in Ontario. It was unable to determine unambiguously whether dugouts were used prehistorically or if they were a technological adoption by Indians in the historic period. Regardless, it appears that dugouts were not rare in Ontario even into the early 20th century.
(The image at the top of this post shows the dugout discovered in 1965 near Weymouth, Massachusetts, and on display in the Tufts Library in Weymouth. It is from The New England Indians: An Illustrated Sourcebook of Authentic Details of Everyday Indian Life, 2nd ed., by C. Keith Wilbur. Link below.)
, Bruce Bourque explains that it's the area consisting of Maine, New Brunswick, and Quebec south of the St. Lawrence River. (Geographically, it makes sense to group these areas together as they do in fact cover a single huge peninsula. Most of Maine's [arrow-straight] border with New Brunswick, on the other hand, is entirely artificial.)
, by David S. Cook, was originally published in 1985, and republished in 1997. This is a well-detailed book describing dozens of individual canoe routes, including both water and portage portions. Many of the original native place-names appear with the current names, and many anecdotes and legends accompany the various route descriptions. (The phrase "Above the Gravel Bar" is the translation of one such ancient place-name, but this brings up a gripe: I've seen at least two, maybe three totally different native names that purportedly translate as "where we speared sturgeon by torchlight." Maybe they loved caviar so much that they created two totally different languages to describe it?) Several maps are included which are helpful, but more detailed maps would make a good book better. Three or four chapters precede the route descriptions, covering subjects such as the importance of the beaver in establishing and maintaining some of the routes; descriptions of the region's geography and canoes; and some canoe tripping techniques.
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(Copper Canoe Press, 1960). One of their more interesting rafts was of A-frame construction, and served somewhat the same purpose as the Landing Ship Docks 
