Sales of wood by landowners more than two centuries ago
have caused irreversible changes in the composition of
the forests of southern Québec. The beeches and
yellow birches (commonly called cherry trees) have practically
disappeared from several forests and been replaced by species
such as hickory, which is so common today that people think
they are typical of the mature forest.
This is the conclusion reached by two Université de
Montréal botanists, Jacques Brisson and André Bouchard,
in a study that will appear this spring in the journal Écoscience. “Until
recently it was believed that the hickory-sugar maple forest
was the climax forest of the Upper Saint Lawrence,” explain
Mr. Bouchard, director of the Plant Biology Research Institute
(IRBV). “That’s wrong. The forest that the
colonists saw when they arrived here was composed of sugar
maple, as well as beech, hemlock, oak, larch, yellow birch
and even spruce. Since that time, many of these species
can only be found occasionally or have disappeared from
the region.”
To reconstitute the pre-colonial forest, the researchers
had to resort to an odd methodology: a study of notarized
deeds kept in the municipal and provincial archives. You
have to bear in mind that the population of Lower Canada
was not well educated in the early days; notaries officiated
at all commercial transactions. For example, the sale of
a pile of wood for heating or construction was commonly
recorded in a deed of sale signed by a notary. The deed
contained details of the species of wood sold, the volume,
price, etc. After searching through some 500,000 notarized
deeds, the archivist-botanists selected 119 acts for detailed
study. Since the land has been surveyed accurately since
the beginning of colonization, they were able to locate
60 woodlots from the beginning of the 19th century that
had not been converted to pasture, cornfields or highways.
With the old records, they could compare the old growth
forests with today’s forests—a real journey
in time. “We noted that human activity for close
to two centuries, especially between 1820 and 1840, was
enough to make the beech and yellow birch disappear almost
completely,” note Mr. Brisson.
Jacques Brisson and André Bouchard confirmed their
hypothesis when they examined the composition of the Muir’s
forest, one of the only wooded areas in the Saint Lawrence
plain that has been spared direct human intervention. Here
they found beeches and maples dating back 250 years or
more. “Some were there at the time the first colonists
arrived,” mentions Jacques Brisson, who discovered
this amazing forest during his master’s degree studies.
The Muir’s forest is now a protected space—and
a Université de Montréal open-air laboratory.
Mr. Brisson, a professor in the Department of Biology and
a researcher at the IRBV, has conducted several studies
in this forest.
Researcher: Jacques Brisson
Telephone: (514) 872-1437
Email: jacques.brisson@umontreal.ca
Funding: Natural Sciences and Engineering Research Council
of Canada
