The distribution of plant species within Outaouais area is determined by several factors, including microclimate, topography and geology. The carbonate-rich soils common in the region support a rich diversity of plants.
Nearly 90% of the area is forested, presenting some of the most ecologically diverse woodlands in central Canada. An afternoon’s walk can take the hiker through deciduous-dominated forests of sugar maple, American beech, yel low birch and eastern hemlock, then through coniferous-dominated black spruce and balsam fir forests typically asso ciated with the boreal forest. Red and white oaks dominate along the steep slopes of the Eardley Escarpment.
Remnant stands of the area original mature white pine forests are very rare, as most of these magnificent trees were harvested for the square timber trade in the 1800s. Similarly, small virgin stands of white spruce and balsam fir are found only in a few remote locations. Virgin stands of eastern hemlock are also rare, but can be found on some cool, north-facing slopes. Maintaining the health of these species is very important, as they contain the genetic diversity of the once-vast forests of the St. Lawrence Lowlands.
More than 1100 species of vascular plants have been documented in this region. Notable are the more than 40 species of orchids, including showy lady’s slipper, green adder’s mouth, grass pink and rose pogonia. Many orchids thrive in the wet, rich environ ment of marshes, fens and bogs.