Tall
Grass Prairie & Savanna
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The Truth about Tallgrass
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What are tallgrass communities?
“Tallgrass communities” –
also known as tallgrass prairies and savannas – are natural
grasslands with a great diversity of grasses, wildflowers and
animal life. In Ontario, tallgrass is teeming with wildlife,
including:
- over 200 species of plants, such as blazing-star and
wild bergamot;
- many birds, such as bobolinks, savanna sparrows
and northern bobwhite quail;
- mammals, such as deer, meadow
voles, and badgers; and
- a fascinating diversity of insects,
from butterflies and damselflies to ants, leafhoppers and
ladybeetles.
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Where are they? Where have they gone?
Tallgrass was once found throughout the
central U.S. and in southern Ontario and Manitoba. It covered an
estimated 90 million hectares – about the size of British Columbia.
Now only 1.5 million hectares (about one percent) remains – about the
size of half of Vancouver Island. In southern Ontario, tallgrass once
covered approximately 1000 km2 – less than 3 percent remains!
Most
tallgrass communities have been lost over the past 200 years due to
human use of the land for agriculture and urbanization. Click
here to see a map of the original extent of tallgrass prairie
and savanna.
Why are they important?
Tallgrass…
- is a globally imperiled
ecosystem and one of the most endangered ecosystems in Canada;
- is
part of Ontario’s natural heritage;
- provides habitat for a huge
number of wildlife species, including many that are officially
designated as rare at the global, national or provincial level; and
- is home to species such as northern bobwhite which is in danger of
disappearing from Canada. Some tallgrass species, like the greater
prairie chicken and the karner blue butterfly, have already disappeared
from Canada.
What is happening to save tallgrass in
Ontario?
World Wildlife Fund Canada and the
Ontario Ministry of Natural Resources have developed a recovery plan for
Ontario’s tallgrass communities. Local groups and individuals are hard
at work across the region to save and recover tallgrass.
Tallgrass Ontario is working to raise awareness,
coordinate recovery efforts, and help provide local groups with the
tools they need to do the job.
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Savanna
For many people "savanna"
conjures up images of African plains with zebras and wildebeests
grazing beneath scattered trees. Savanna is indeed the term
applied to natural areas of mostly grasses with scattered
open-grown trees. It comes as a surprise to many that savannas can
be found in Ontario! Many of the largest and most significant of
these are within the Carolinian life zone of southwestern Ontario.
Typical savanna and prairie plant species include Big Bluestem,
Little Bluestem, Indian Grass, and Switchgrass. Wild Bergamot,
Black-eyed Susan, and Bush clover are typical non-grass species
present. In areas of more moisture, sedges and ferns are present.
Savannas and prairies develop on sites which are subject to
environmental stresses, typically fire, drought, spring flooding,
and warmer than usual local climates. Prairie occurs where these
effects are most severe, while savanna grows where these stresses
are not so pronounced.
In the Carolinian region, trees which characterize savannas are
the oaks and hickories, and occasionally pines. Pin Oak, Swamp
White Oak, and Bur Oak dominate wetter sites. Black Oak, White
Oak, and Pignut Hickory are found on intermediate sites and the
dryer sites may also have White Pine or Red Pine. In very dry
sites, Eastern Red Cedar may also occur with oak and pine.
Savanna sites in the Carolinian
region are found mostly on very sandy soils. The largest and most
significant remnants are at Windsor, Walpole Island, the Port
Franks area on the Lake Huron shore, north of Turkey Point, Pelee
Island in Lake Erie, and High Park in Toronto. High Park provides
a good example of how savanna areas will grow into less open
forests in the absence of regular disturbance
Savanna sites accessible for public exploration can be found at
Ojibway Prairie in southwest Windsor (at Matchett and Titcombe
roads); Pinery Provincial
Park; Stone Road Alvar on Pelee Island;
Turkey Point Provincial Park; and High Park in Toronto. Other
publicly accessible sites exist, call your local Ontario Ministry
of Natural Resources or local Conservation Authority office for
specific locations.
Human development of savanna and
prairie has eliminated or degraded much of these areas.
Consequently, much of the flora associated with these uncommon
sites is considered rare in Ontario. Some are even considered
endangered (Pink Milkwort, Slender Bush Clover, and White Prairie
Gentian, to name a few). The conservation of these rare species,as
well as the more common ones, is dependent on the protection of
their habitat. Therefore, the careful stewardship of prairie,
savanna, and woodland remnants is critical. |
Prairie
Prairie is a natural community that is
dominated by grasses rather than by trees, as in a forest. Growing with
the grasses are many other kinds of non-grassy herbaceous plants known
by the collective name of "forbs". On moist soils, prairie
blends into marshlands dominated by sedges rather than grasses.
Scattered shrubs may be present, however trees are absent.
The term "savanna" is applied
to places where prairie-type vegetation grows within widely spaced
trees.
The term "prairie" is usually
associated with the central part of North America and many people are
surprised to learn that prairie areas exist in southern Ontario. These
sites are scattered sporadically across the landscape from Windsor to
the eastern part of the province. However, it is in the southwest, the
Carolinian life zone, that the largest areas of prairie remain. In fact,
historical accounts and present day physical evidence tell us that
prairie was once widespread in the extreme southwest of Ontario,
primarily in Essex and Kent counties. Smaller prairie sites also are
found in areas of Lambton and Brant counties, Haldimand-Norfolk, and
near Toronto. The largest and best known remnants are at Windsor and
Walpole Island.
Since prairie areas are so rare in Ontario, the flora and fauna
associated with them are also uncommon in the province. Approximately
20% of plants designated as rare in Ontario are associated with prairie.
Examples include Culver's Root, Tall Ironweed and Prairie Rose. At
Walpole Island, there are seven species of plants growing which are not
known elsewhere in Canada. The Greater Prairie Chicken was present in
the Windsor area until the late 19th century.
The rich fertility of prairie soil, coupled with the fact that few trees
are present, made these areas ideal for agricultural development. These
areas support some of the most productive corn and soya bean operations
in Ontario, much the same as wheat has replaced much of the native
vegetation of the vast mid-continent prairie. Of the estimated one
million square kilometres of tall grass prairie that once occurred in
North America, less than one six-hundredth of one percent remains.
Hence, conservation of remaining natural prairie and its rare species is
vital.
Fire is a key component of maintaining
prairie vegetation. In order to mimic this formerly natural process,
controlled fires are applied as a management tool at many Ontario
prairie sites owned by conservation agencies.
An excellent place to see native prairie
in Ontario is at Ojibway Prairie in Windsor. A Provincial Nature Reserve
and adjacent municipal park and visitor's centre all provide ample
opportunity to experience this unique part of Carolinian Canada. These
areas can be found along Matchette Road at the southwest edge of the
city.
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