Description
The Ausable River has, over thousands of years, proved its power, carving a dramatic and steep-sided gorge and valley northeast of the village of Arkona. Due to its ruggedness and inaccessability, the 19-km gorge -- in places more than 50-m deep, and home to a number of picturesque waterfalls -- is one of the larges river valleys remaining in a natural condition in the region. A forested corridor with Carolinian species such as Black Maple, Eastern Flowering Dogwood, Chinquapin Oak, and Sycamore follows the winding valley.
Generations of rock hounds have made pilgramages to Rock Glen Conservation Area, wher ethe erosive power of the Ausable River has revealed some of the best Devonian Era fossils in North America. Fossilized plants, sponges, coral, and fish that date back more than 350 million years can be found in the exposed beds of the Rock Glen Gorge at the bottom of an 11-m high waterfall.
In the mid-1970s, a local naturalist group, Lambton Wildlife Incorporated (LWI), created a 14-km trail through the Ausable River Valley. Running from Hungry Hollow to Highway 7, the Ausable Trail follows the rugged landscape of this scenic gorge. |
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LWI also conducted a landowner contact program in 1993, talking with hundreds of property owners along the Ausable Gorge and reaching "handshake stewardship agreements" with the many people who are protecting the banks of the river.
The Ausable Bayfield Conservation Authority (ABCA) was established in 1946, and holds the distinction of being the first conservation authority formed in Ontario. The ABCA owns and protects 3,635 ha of land within the drainage basins of the Ausable and Bayfield Rivers, Parkhill Creek, and the gullies between Bayfield and Grand Bend that drain directly into Lake Huron (taken from Carolinian Canada Signature Sites Guide by Lorraine Johnson 2005).
Vegetation
Ausable River (Life Science Inventory Check-sheet in Eagles & Beechey, 1985):
An extensive forested corridor follows the winding valley for about 15 km. The vegetation along its length includes: deciduous woods on the valley slopes and adjacent tablelands (associations of sugar maple, white ash, beech, oak, basswood, mixed with other species), hawthorn scrub and young sucessional woods (aspen, black walnut, ash) coniferous reforestation floodplain forests of black maple- black walnut- oak- basswood, ash- silver maple bottomlands, shrub thickets (dogwood- ninebark) and marsh, tall riverbank meadows, and prairie associations.
Representation
Ausable River (Life Science Inventory Check-sheet in Eagles & Beechey, 1985):
Because of its ruggedness and inaccessibility, this dramatic and ecologically diverse candidate nature reserve is one of the largest river valley corridors left in a natural condition in Site District 7-2. It crosses two physiographic regions, the Horseshoe Moraines and the Huron Slope, and provides representation of the features of both. Much of the forest along the valley has been lumbered. Also the general boundary of this site incorporates some agricultural and cleared land of little natural value along the valley.
Landform
Ausable River (Life Science Inventory Check-sheet in Eagles & Beechey, 1985):
Between Arkona and Thedford, the Ausable River has cut a steep-sided gorge and valley over 50 m deep through the Wyoming till moraine, into the underlying Devonian bedrock, and further north towards Thedford, across plain deposits. In the south, near Arkona, the river penetrates many metres into the highly fossiliferous limestone and shale of the Widder, Hungry Hollow and Arkona Formations.
References
* Allen, G.M., P.F.J. Eagles and S.D. Price (eds.) 1990. Conserving Carolinian Canada: Conservation Biology in the Deciduous Forest Region. University of Waterloo Press, Waterloo. 346 pp.
* Eagles, P.F.J. and T.J. Beechey (eds.) 1985. Critical Unprotected Natural Areas in the Carolinian Life Zone of Canada. Final Report, Identification Subcommittee, Carolinian Canada. The Nature Conservancy of Canada, The Ontario Heritage Foundation and World Wildlife Fund (Canada). 400 pp.
* Hilts, S.G. and F.S. Cook, (eds). 1982. Ausable River North Site Report. Pp. 62-63, in, Significant Natural Areas of Middlesex County. McIlwraith Field Naturalists, London and School of Rural Planning and Development, University of Guelph. 189 pp.
* Hilts, S.G. and F.S. Cook, (eds). 1982. Ausable River South Site Report. Pp. 64-65, in, Significant Natural Areas of Middlesex County. McIlwraith Field Naturalists, London and School of Rural Planning and Development, University of Guelph. 189 pp.
© Natural Heritage Information Centre, 1998
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