The Niagara Escarpment What is the Escarpment? Geology   Natural Features Social and Economic Importance What Is The Niagara Escarpment? Geographers often call the Niagara Escarpment the most prominent topographic feature of southern Ontario. But if you stand at the bottom of its cliffs and crane your neck upwards to glimpse tiny, 1000-year-old cedar trees clinging to the precipice, or find your first Hart's tongue fern in the rich, upland forests, then you are sure to call the Escarpment magnificent and wonderful - a priceless treasure of Ontario's natural heritage. Historically, because of its challenging topography, human settlement of the Niagara Escarpment did not happen as quickly and intensively as settlement of the rolling countryside around it. In the past 50 years, physical restrictions have not hindered development on the Escarpment nearly as much. The result has been the loss of special environmental features and natural areas. These threats to the Escarpment environment are cause for concern. The challenge for environmentally conscious citizens and organizations is to ensure that development is controlled to an extent that the Escarpment's natural features and functions remain intact as much as possible, and to advocate better protection and conservation. Our attention focuses on the part of the Niagara Escarpment that is defined and regulated under Ontario law - the green corridor 725 kilometres long from Queenston near Niagara Falls on the Niagara River past Cabot Head to Tobermory, at the tip of the Bruce Peninsula. Yet this thin strip is only part of a large, horseshoe-shaped ridge. The Escarpment enters Ontario from New York state at Queenston, then winds its way north to Tobermory. It can be identified under the waters of Georgian Bay, on Manitoulin Island, and on the islands to the west, through Michigan's upper peninsula and into Wisconsin, where it is highly visible near Green Bay on the Door Peninsula. View map of Niagara Escarpment Plan Area The Geology Of The Niagara Escarpment The Geological Survey of Canada first referred to the Niagara Escarpment in 1864, identifying it as a "step in the countryside." It is a complex land form consisting of sedimentary bedrock of marine origin overlain by glacial deposits. The limestones, dolostones, shales and sandstones of the Niagara Escarpment bedrock date from the Ordovician and Silurian Periods of the geological time scale. They were formed between 425 and 450 million years ago. But it would be a mistake to say that the Escarpment was formed during this time, for the Escarpment we see today is the result of erosion that has occurred over the last 250 million years or so. The Niagara Escarpment is not the result of a fault (a fracture in the earth's crust), as some escarpments are, but instead is a "cuesta" which was formed by differential erosion. Simply put, this means that underlying, soft rocks (shale) eroded away relatively quickly and the more resistant caprock (limestone and dolostone) was undermined and broke off, creating a cliff-like slope. Formation of the Escarpment began somewhere to the north and east of its present location. Through continuous erosion, it receded to its current position and became the dominant feature of the southern Ontario landscape. Albion Falls in Hamilton's Red Hill Valley Major rivers eroded large valleys back into the Escarpment, such as the Dundas Valley, the Beaver Valley, the Hockley Valley, the Pine Valley and Owen Sound. In the stream erosion process, islands of bedrock called outliers were formed. Examples are found near Milton, in Mono Cliffs Provincial Park northeast of Orangeville, near Creemore in Simcoe County, and on Cape Rich near Meaford in Grey County. About two million years ago, the world entered an Ice Age. Along with the rest of the northern half of North America, the Niagara Escarpment lay buried from time to time under several hundred metres of ice. However, the oldest Ice Age (glacial) deposits associated with the Escarpment today are less than 25,000 years old. The glaciers also left trademarks such as the polished and scratched bedrock surfaces and boulders (called erratics) that lie haphazardly in forests and fields. Glaciers left behind deposits of sand, gravel and clay (till) in the form of various topographic features - particularly moraines - that cover the bedrock. For example, in Caledon, the Escarpment slope is completely buried under a moraine, but the bedrock slope is reflected in the slope of the glacial deposits lying over the bedrock. Parts of the Escarpment in Dufferin County are also buried, but by contrast to Caledon, the Escarpment slope is not visible in the glacial deposits over the slope in Dufferin. In many places along the Escarpment, steep bedrock cliffs are exposed above glacial till. This is especially notable on the Bruce Peninsula. Glaciers left the Escarpment about 13,000 years ago. As they retreated, water was left by the melting glaciers. Discharge channels formed and washed out sand and gravel from the glaciers. The sand and gravel then accumulated in large deposits. Some of the channels were laid down in canyons between outliers and the main Escarpment. The Nassagaweya Canyon near Milton is one example. The deglaciated surface of the Niagara Escarpment became the terrain that began supporting plant and animal life - the foundations of its present plant and animal communities. The evolution of plant life is recorded in pollen-bearing muds that researchers have sampled from the bottom of the Escarpment's lakes, ponds and swamps. Flowerpot Island

Ontario's Niagara Escarpment has gained international ecological recognition over the past decade.

The Cliff Ecology Research Group at the University of Guelph has discovered that the small, slow-growing eastern white cedar trees (Thuja occidentalis) clinging to Escarpment cliffs are very old - many over 1000 years, the oldest 1650 years. This cliff ecosystem constitutes the oldest "old growth forest" in eastern North America. Studying these living trees, as well as dead ones at the base of the cliffs, provides invaluable information about past climatic conditions and trends that can help us understand the biological impacts of climate variation and change.

The Escarpment's cliff ecosystem constitutes the oldest "old growth forest" in eastern North America.

The southernmost part of the Escarpment in Ontario is in the Carolinian or deciduous forest region. Common tree species include sugar and black maple, red, white, black and chinquapin oaks, bitternut, shagbark and pignut hickories; more rare but typical species are tulip tree and cucumber tree. All of the Escarpment north of the Niagara Peninsula is in the Great Lakes-St. Lawrence forest region. Typical tree species are beech, white birch, trembling aspen, eastern white cedar, balsam fir and jack pine (at the southern limit of its range), as well as maples and oaks.

The Escarpment's many sugar maple forests contain American ginseng, a species considered endangered. Some plant species, such as lakeside daisy, dwarf lake iris and Hill's thistle, are found nowhere else in the world except near the Great Lakes; these three species are quite common on the Bruce Peninsula and Manitoulin Islands parts of the Escarpment.

Hart's Tongue Fern is found nowhere else in Canada

Of the bird species that breed on the Niagara Escarpment, 25 are "species at risk" - that is, considered nationally or provincially endangered, threatened with endangerment, or vulnerable to decline. These include the bald eagle, red-shouldered hawk, black tern, Louisiana waterthrush and hooded warbler.

Other animal species at risk include the northern dusky salamander (endangered), the eastern massasauga rattlesnake (threatened) and the southern flying squirrel (vulnerable).

Farmers along the Escarpment maintain its strong agricultural heritage. Vineyards and the wine industry of the Niagara Peninsula have enjoyed tremendous economic growth, as well as international recognition, over the past 20 years. Gravel-rich, sandy to clay loam soils, combined with unique micro-climate, good drainage and better grape varieties, now produce some very fine wines, especially Chardonnays and the innovative "ice wines." The wine industry is making an increasingly significant contribution to the economy of not only the Niagara Peninsula, but the province as a whole. Niagara wineries are also a travel destination for both motorists and Bruce Trail hikers. Several of the wineries have restaurants as part of their operations.

Tender fruit-growing at the base of the Escarpment along the Niagara Peninsula still survives despite the great pressure from urban growth since the 1960s. Apple growers continue a decades-old tradition in the Beaver Valley of Grey County. There is mixed farming (dairy, grains, market gardening) throughout the central portions of the Escarpment and an important beef cattle industry in Bruce County.

Much of the highest-quality aggregate resources (sand, gravel and stone) in Ontario are extracted from the bedrock and moraines of the Niagara Escarpment. Aggregate deposits closest to the markets of the Greater Toronto Area are under the greatest pressure for the opening up of more pits and quarries, especially in Caledon and northern Halton Region. While aggregate operations provide substantial benefits to the Ontario economy, they can cause major environmental damage, nuisance impacts and social disruption in the process.

The Niagara Escarpment is much prized as a place to live for full-time residents, urban commuters, cottagers and weekenders. In fact, one of the greatest land-use pressures on the Escarpment is for more residential development, especially in the rural landscape.

Escarpment-based recreation has become crucial to local economies. Recreational land uses that may cause some degree of environmental harm include golf courses and ski hills (such as in the Blue Mountains, the Beaver Valley and the Hockley Valley).

The Escarpment provides a wide array of more benign outdoor pursuits - hiking the Bruce Trail, bird-watching, nature photography, cross-country skiing, snowshoeing, angling and landscape painting. People enjoying these activities also use local services such as bed and breakfast homes, hotels, restaurants and stores. Low-impact recreational use of the Escarpment is roughly estimated to pump upwards of $100 million into community economies each year.

Low-impact recreational use of the Escarpment pumps $100 million into community economies each year.

The Niagara Escarpment's value to Ontario society lies partly in its economic potential - in other words, the value of extracting its resources together with that of retaining natural areas for recreational purposes. But the Escarpment's value also lies in its simply being there, whether humans make use of it or not. As the last, essentially continuous forested corridor in southern Ontario, it holds tremendous ecological significance and has much to teach us about nature.