Download a PDF of the updated Checklist of - Royal Botanical ...

Some of the cooler ravine slopes are characterized by more northern sugar
maple (Acer saccharum)/beech (Fagus grandifolia)/hemlock (Tsuga
canadensis) forests, with typical herbaceous associates like starflower
(Trientalis borealis) and, rarely, shinleaf (Pyrola elliptica). Moist depressions
throughout the Cootes Paradise forest support stands of black walnut
(Juglans nigra) and sassafras (Sassafras albidum).
Large areas of the understory in all forest types in Cootes Paradise are
dominated by invasive shrub species, predominantly honeysuckles (Lonicera
spp.). The herbaceous vegetation in many places is a monoculture of garlic
mustard (Alliaria officinalis) or swallow-wort (Cynancum spp.). Invasive
species problems are exacerbated by an extensive and growing network
of informal footpaths and bike trails.
While the ravine slopes may represent primary forest, most of the upland
areas of Cootes Paradise have been cleared for pasture or cultivation in
the past. These second growth areas now include a mosaic of old-field
meadows, white pine (Pinus strobus) and poplar (Populus spp.) plantations,
and successional thicket communities.
HENDRIE VALLEY
Hendrie Valley Sanctuary is very similar to Cootes Paradise physiographically
and floristically. Perhaps the most significant difference between the two
areas is the greater success of the restoration of submergent plant communities
in Hendrie Valley compared with Cootes Paradise. A large berm
separates the Hendrie Valley floodplain ponds from the Grindstone Creek,
and the Gardens’ staff have for the most part been able to exclude carp from
these ponds. As a consequence, submergent densities in Hendrie Valley are
very high, comparable to those of undisturbed eutrophic wetlands.
vii
ROCK CHAPEL
Rock Chapel Sanctuary includes Niagara Escarpment cliff-face and forested
talus slope habitat, and secondary forest and successional old-field
communities. The talus slope forest is dominated by sugar maple.
Chinquapin oak (Quercus muhlenbergii) is common on drier ridges along
the slopes, while black walnut, basswood (Tilia americana), Manitoba
maple (Acer negundo) and black maple (Acer saccharum ssp. nigrum) form
small stands in the frequent groundwater seeps. Poison ivy (Rhus rydbergii)
dominates the understory, giving way to pale jewelweed (Impatiens
palida) along wet slopes. This area is particularly rich in spring wildflowers,
and is the home of the largest remaining population of the endangered
red mulberry (Morus rubra) in Canada.
The cliff-face community at Rock Chapel is limited in area, but does include
eastern white cedar (Thuja occidentalis) that are over 300 years old (Kelly and
Larson, 2001). The area above the cliff has all been cleared and cultivated
in the past, and is now in various stages of succession back towards a
maple forest community. Gardens’ staff have systematically allowed areas of
the fields to revert to natural habitat as a study of succession.
BERRY TRACT (VALLEY ROAD PROPERTIES)
Rock Chapel and Berry Tract (originally called the Valley Road Properties)
protect adjacent sections of a natural community that extends along the
Niagara Escarpment from Spencer’s Falls Conservation Area in Hamilton
to Waterdown Woods in Halton. As such, the talus forest at Berry Tract
is very similar to that at Rock Chapel. However, it is much more fragmented
by roads and housing developments. As a result, the understory is now
dominated almost exclusively by exotic species, particularly pale swallowwort
(Cynanchum rossicum). The abandoned orchard below the Berry Tract
talus is characterized by hawthorn (Crataegus spp.) thickets, but canopy
trees are beginning to establish, particularly in moister gullies. A small
seasonally wet opening along the road supports a diverse mix of sedges
and rushes, as well as the provincially rare winged loosestrife (Lythrum
alatum). This species has naturally established at this location since 1969.
viii