bands of cattail and some alder growth. The ridges of the site extend from the center of the conservation area westwards. There is a wide mixture in the vegetation from early succession poplars and shrubs to some very large mature specimens of white pine, maple, and ash. A section of this area includes a variety of hard and softwood plantations established by the Canadian Forest Service. Hydrological values Mer Bleue drains both westward into Green's Creek and eastward into Bear Brook. Drainage was formerly through small creeks, which now have been modified through a series of ditches dug in the late 19th century. These ditches are no longer functioning efficiently due to the many beaver ponds, which started up in the late 1950s. As in a typical bog, the water level is at or near the surface for most of the year. Much of the bog is surrounded by the "lagg" that is basically a moat of standing or slow flowing water found between the outer perimeter of the bog and the land. Flooding is controlled naturally through beaver dams and the ability of sphagnum to absorb large amounts of water. The bog receives most of its water in the form of atmospheric precipitation. Flow velocities of ground and surface waters are very low given the impermeability of the underlying clay soils, the absorption qualities of sphagnum and the presence of numerous beaver dams. Shoreline stabilization is not a significant concern as the impact of water on the ridges is minimal and most of the land is relatively flat. Flora Regionally significant vegetation Beech-maple forests (upland tolerant deciduous forest) rare in Ottawa-Carleton region Swampy forests of maple, cedar, and hemlock (lowland tolerant forests) are regionally significant Black spruce-larch forests (lowland intolerant coniferous forests), rare in the Ottawa district Open bog, low-shrub bog, and treed bog are highly significant within an Ottawa District and Southern Ontario context Bog pool is regionally significant Nationally significant flora Porsild's cottongrass (Eriophorum x porsildii, a hybrid of E. vaginatum and E. chamissonis), Cyperaceae Southern twayblade (Listera australis), Orchidaceae Torrey's manna grass (Torreyochloa pallida), Poaceae Provincially significant flora Black-berried highbush blueberry (Vaccinium corymbosum) Downy goldenrod (Solidago puberula) Drooping manna grass (Glyceria x laxa) Folliculata sedge (Carex folliculata) Greene's rush (Juncus greenei) Ground pine (Lycopodium obscurum) Hayden's sedge (Carex haydenii) Heart-leaved tearthumb (Polygonum arifolium) Large purple-fringed orchid (Habenaria fimbriata) Long manna grass (Glyceria melicaria) Marsh dandelion (Taraxacum