Thousand Islands – Frontenac Arch

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An outcrop of the Frontenac Axis near Cornwall, Ontario Canadian Shield.jpg
An outcrop of the Frontenac Axis near Cornwall, Ontario

The Thousand Islands – Frontenac Arch region or the Frontenac Axis is an exposed strip of Precambrian rock in Canada and the United States that links the Canadian Shield from Algonquin Park with the Adirondack Mountain region in New York, an extension of the Laurentian mountains of Québec. The Algonquin to Adirondacks region, which includes the Frontenac Axis or Arch, is a critical linkage for biodiversity and resilience, and one with important conservation potential. [1] The axis separates the St. Lawrence Lowlands and the Great Lakes Lowlands. It has many distinctive plant and animal species. [1] It is one of four ecoregions of the Mixedwood Plains.

The Precambrian is the earliest part of Earth's history, set before the current Phanerozoic Eon. The Precambrian is so named because it preceded the Cambrian, the first period of the Phanerozoic eon, which is named after Cambria, the Latinised name for Wales, where rocks from this age were first studied. The Precambrian accounts for 88% of the Earth's geologic time.

Canada Country in North America

Canada is a country in the northern part of North America. Its ten provinces and three territories extend from the Atlantic to the Pacific and northward into the Arctic Ocean, covering 9.98 million square kilometres, making it the world's second-largest country by total area. Canada's southern border with the United States is the world's longest bi-national land border. Its capital is Ottawa, and its three largest metropolitan areas are Toronto, Montreal, and Vancouver. As a whole, Canada is sparsely populated, the majority of its land area being dominated by forest and tundra. Consequently, its population is highly urbanized, with over 80 percent of its inhabitants concentrated in large and medium-sized cities, many near the southern border. Canada's climate varies widely across its vast area, ranging from arctic weather in the north, to hot summers in the southern regions, with four distinct seasons.

United States federal republic in North America

The United States of America (USA), commonly known as the United States or America, is a country composed of 50 states, a federal district, five major self-governing territories, and various possessions. At 3.8 million square miles, the United States is the world's third or fourth largest country by total area and is slightly smaller than the entire continent of Europe's 3.9 million square miles. With a population of over 327 million people, the U.S. is the third most populous country. The capital is Washington, D.C., and the largest city by population is New York City. Forty-eight states and the capital's federal district are contiguous in North America between Canada and Mexico. The State of Alaska is in the northwest corner of North America, bordered by Canada to the east and across the Bering Strait from Russia to the west. The State of Hawaii is an archipelago in the mid-Pacific Ocean. The U.S. territories are scattered about the Pacific Ocean and the Caribbean Sea, stretching across nine official time zones. The extremely diverse geography, climate, and wildlife of the United States make it one of the world's 17 megadiverse countries.


The Thousand Islands in the Saint Lawrence River have a distinctive flora and fauna and are a part of the biological corridor.

Thousand Islands archipelago of 1,864 islands along the Canada-U.S. border in the Saint Lawrence River

The Thousand Islands constitute an archipelago of 1,864 islands that straddles the Canada–US border in the Saint Lawrence River as it emerges from the northeast corner of Lake Ontario. They stretch for about 50 miles (80 km) downstream from Kingston, Ontario. The Canadian islands are in the province of Ontario and the U.S. islands in the state of New York.

Saint Lawrence River Large river in eastern Canada and the United States, flowing into the Gulf of Saint Lawrence

The Saint Lawrence River is a large river in the middle latitudes of North America. The Saint Lawrence River flows in a roughly north-easterly direction, connecting the Great Lakes with the Atlantic Ocean and forming the primary drainage outflow of the Great Lakes Basin. It traverses the Canadian provinces of Quebec and Ontario, and is part of the international boundary between Ontario, Canada, and the U.S. state of New York. This river also provides the basis of the commercial Saint Lawrence Seaway.


The bedrock is mostly gneiss, granite and marble, more than a billion years old. [2] The Frontenac terrain is the youngest of the Ontario portions of the arch, dated at 1.2 billion years old. [3] These rocks were once part of a large mountain chain of the ancient supercontinent of Rodinia. There is also a meteor crater near Holleford, where the shield meets the limestone plains of southeastern Ontario. [4]

Bedrock Lithified rock under the regolith

In geology, bedrock is the lithified rock that lies under a loose softer material called regolith at the surface of the Earth or other terrestrial planets. The broken and weathered regolith includes soil and subsoil. The surface of the bedrock beneath the soil cover is known as rockhead in engineering geology, and its identification by digging, drilling or geophysical methods is an important task in most civil engineering projects. Superficial deposits can be extremely thick, such that the bedrock lies hundreds of meters below the surface.

Gneiss A common high-grade metamorphic rock

Gneiss is a common and widely distributed type of metamorphic rock. Gneiss is formed by high temperature and high-pressure metamorphic processes acting on formations composed of igneous or sedimentary rocks. Orthogneiss is gneiss derived from igneous rock. Paragneiss is gneiss derived from sedimentary rock. Gneiss forms at higher temperatures and pressures than schist. Gneiss nearly always shows a banded texture characterized by alternating darker and lighter colored bands and without a distinct foliation.

Granite A common type of intrusive, felsic, igneous rock with granular structure

Granite is a common type of felsic intrusive igneous rock that is granular and phaneritic in texture. Granites can be predominantly white, pink, or gray in color, depending on their mineralogy. The word "granite" comes from the Latin granum, a grain, in reference to the coarse-grained structure of such a holocrystalline rock. Strictly speaking, granite is an igneous rock with between 20% and 60% quartz by volume, and at least 35% of the total feldspar consisting of alkali feldspar, although commonly the term "granite" is used to refer to a wider range of coarse-grained igneous rocks containing quartz and feldspar.


The area is distinctive for having tree species typically found further south, and reaching their northern limits. [5] One example is pitch pine ( Pinus rigida ). Shallow soils and recurring fire have also produced unusual fire barren communities. [6] These provide habitat for rare plants, such as bear oak ( Quercus ilicifolia ) and deerberry ( Vaccinium stamineum ), as well as rare animals, such as the five-lined skink ( Plestiodon fasciatus ) and gray rat snake ( Pantherophis spiloides ). [7] There is high bird diversity, including the cerulean warbler, considered nationally endangered owing to the destruction of forests. Although the most important factor producing the fauna and flora is likely the bed rock, the moderating effect of the Great Lakes may also be factor. Also, some northern species extend their range south, drawn by the rugged granite landscapes of the Canadian Shield.

<i>Pinus rigida</i> species of plant

Pinus rigida, the pitch pine, is a small-to-medium-sized pine. It is native to eastern North America, from central Maine south to Georgia and as far west as Kentucky, and in two pockets along the St. Lawrence River in southern Quebec and Ontario. It is found in environments which other species would find unsuitable for growth such as acidic, sandy, and low nutrient soils. This species occasionally hybridizes with other pine species such as loblolly pine, shortleaf pine, and pond pine ; the last is treated as a subspecies of pitch pine by some botanists.

<i>Quercus ilicifolia</i> small shrubby oak

Quercus ilicifolia, commonly known as bear oak or scrub oak, is a small shrubby oak native to the eastern United States and southeastern Canada. Its range extends in the United States from Maine to North Carolina, with reports of a few populations north of the international frontier in Ontario. The name ilicifolia means "holly-leaved."

<i>Vaccinium stamineum</i> species of plant

Vaccinium stamineum, commonly known as deerberry, tall deerberry, squaw huckleberry, highbush huckleberry, buckberry, and southern gooseberry, is a species of flowering plant in the heath family. It is native to North America, including Ontario, the eastern and central United States, and parts of Mexico. It is most common in the southeastern United States.

The basic ecosystem type of the area is temperate deciduous forest. The area has a long history of logging, which has depleted these forests of larger trees. Settlement tends to have occurred in the areas of deeper soil, and fire has particularly influenced the uplands. Reference to the forest descriptions of early surveyors has documented decline in species such as hemlock, which were preferentially removed for leather tanning. [8] Criteria for restoring these forests have been established, and include increased tree size, spring ephemeral abundance, and coarse woody debris. [9] Pollen cores from Lanark County provide information about longer term trends in forest cover. [10]

Temperate deciduous forest

Temperate deciduous or temperate broad-leaf forests are a variety of temperate forest dominated by trees that lose their leaves each year. They are found in areas with warm moist summers and cool winters. The six major areas of this forest type occur in the Northern Hemisphere: North America, East Asia, Central and Western Europe, Denmark, southern Sweden and southern Norway. Smaller areas occur in Australasia and southern South America. Examples of typical trees in the Northern Hemisphere's deciduous forests include oak, maple, beech and elm, while in the Southern Hemisphere, trees of the genus Nothofagus dominate this type of forest. The diversity of tree species is higher in regions where the winter is milder, and also in mountainous regions that provide an array of soil types and microclimates. The largest intact temperate deciduous forest in the world is protected inside of the six-million-acre Adirondack Park in Upstate New York in the United States.

There is a wide array of wetlands, ranging from larger marshes along the St. Lawrence river, to smaller marshes and bogs along water courses, and large numbers of beaver ponds. The cycles in vegetation in beaver ponds contribute to further wetland diversity; depending upon the amount of beaver activity, there may be open water, marsh, wet meadows or shrub thickets. [11] Some lakes in the area, such as Bob's Lake, also support uncommon species of turtles, such as the map turtles and Blanding's turtles. Where there is marble bedrock, or other sources of calcium, fens may arise. These often have unusual calcium dependent wetland plants. [12]

Blandings turtle species of reptile

Blanding's turtle is a semi-aquatic turtle of the family Emydidae. This species is native to central and eastern parts of Canada and the United States. It is considered to be an endangered species throughout much of its range. Blanding's turtles are of interest in longevity research, as they show little to no common signs of aging and are physically active and capable of reproduction into eight or nine decades of life.

Marble non-foliated metamorphic rock commonly used for sculpture and as a building material

Marble is a metamorphic rock composed of recrystallized carbonate minerals, most commonly calcite or dolomite. Marble is typically not foliated, although there are exceptions. In geology, the term "marble" refers to metamorphosed limestone, but its use in stonemasonry more broadly encompasses unmetamorphosed limestone. Marble is commonly used for sculpture and as a building material.

Fen type of wetland

A fen is one of the main types of wetland, the others being grassy marshes, forested swamps, and peaty bogs. Along with bogs, fens are a kind of mire. Fens are minerotrophic peatlands, usually fed by mineral-rich surface water or groundwater. They are characterised by their distinct water chemistry, which is pH neutral or alkaline, with relatively high dissolved mineral levels but few other plant nutrients. They are usually dominated by grasses and sedges, and typically have brown mosses in general including Scorpidium or Drepanocladus. Fens frequently have a high diversity of other plant species including carnivorous plants such as Pinguicula. They may also occur along large lakes and rivers where seasonal changes in water level maintain wet soils with few woody plants. The distribution of individual species of fen plants is often closely connected to water regimes and nutrient concentrations.

A southern portion of this region was designated a Biosphere Reserve by UNESCO in 2002, the Frontenac Arch Biosphere Reserve. [13] Within this biosphere reserve is the relatively small St. Lawrence Islands National Park. [14] Although it is small, it has many Frontenac Arch species mentioned above, including deerberry, Blanding's turtle, and five-lined skinks. [15] Further north, there is, still a large gap in the ecological link to Algonquin Park. In this gap are smaller parks such as Frontenac Provincial Park and Bon Echo Provincial Park.

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Lanark County County in Ontario, Canada

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Algonquin to Adirondacks Collaborative organization

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Frontenac Arch Biosphere Reserve Biosphere reserve in Canada | designated in 2002

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Keddy Nature Sanctuary

The Keddy Nature Sanctuary consists of approximately one square mile of forest and wetland on the very edge of the Canadian shield, just an hour west of Ottawa on the east side of Lanark County, in Ontario, Canada. It is mostly second growth temperate deciduous forest, interspersed with wetlands and beaver ponds, as well as sedge-dominated rock-ridges. A central ridge has more than twenty hectares of hemlock forest. There are also old fields that remain from pastures created in the previous century. Parts of this property, as well as adjoining lands, are designated as the Scotch Corners Provincially Significant Wetland. The property is one of several protected by the Mississippi Madawaska Land Trust.

Scotch Corners Wetland

Scotch Corners Wetland is a provincially significant wetland complex located in Lanark County, Ontario, Canada. The 202 hectares area has a wide array of wetland types including swamps, marshes, vernal pools, beaver ponds and seepage areas. It forms the headwaters of several creeks that drain into Mississippi Lake.


  1. 1 2 Keddy, Cathy (November 1995). "The conservation potential of the Frontenac Axis: Linking Algonquin Park to Adirondacks" (PDF). The Canadian Parks and Wilderness Society - Ottawa Valley Chapter: 72. Retrieved May 8, 2014.
  2. Eyles, Nick. Ontario Rocks. 2002. Three Billion Years of Environmental Change. Fitzhenry and Whiteside, Markham, Ontario. Chapter 9.
  3. Eyles, Nick. Ontario Rocks. 2002. Three Billion Years of Environmental Change. Fitzhenry and Whiteside, Markham, Ontario. Figure 9.2A
  4. Keddy, P.A. 2008. Earth, Water, Fire. An Ecological Profile of Lanark County. General Store Publishing House, Refrew, Ontario. p. 61-63.
  5. Beschel, R.E., P.J. Webber and R. Trippet. 1962. Woodland transects of the Frontenac Axis region, Ontario. Ecology 43:386-396.
  6. Catling, Paul M and Vivian R. Brownell. 1999. The flora and ecology of southern Ontario granite barrens. Pages 392-405 in Anderson, R.C., J.S. Fralish, and J.M. Baskin (eds). Savannas, Barrens, and Rock Outcrop Plant Communities of North America. Cambridge University Press, Cambridge.
  7. Keddy, Cathy J. 1995. The Conservation Potential of the Frontenac Axis: Linking Algonquin Park to the Adirondacks. Canadian Parks and Wilderness Society, Ottawa, Ontario. 59p.
  8. Keddy, Cathy J. 1993. Forest History of Eastern Ontario. A report prepared for the Eastern Ontario Forest Group, Kemptville, Ontario.
  9. Keddy, P.A. and C.G. Drummond. 1996. Ecological properties for the evaluation, management, and restoration of temperate deciduous forest ecosystems. Ecological Applications 6: 748-762.
  10. Keddy, P.A. 2008. Earth, Water, Fire: An Ecological Profile of Lanark County. General Store Publishing House, Renfrew, Ontario.p. 51-52.
  11. Keddy, P.A. 2008. Earth, Water, Fire: An Ecological Profile of Lanark County. General Store Publishing House, Renfrew, Ontario. Fig. 2
  12. Plants of Lanark County, Ontario--2013 Edition David J. White
  13. Frontenac Arch Biosphere Reserve
  14. Thousand Islands National Park
  15. Species at Risk in the 1000 Islands Ecosystem