Wasaga Beach Provincial Park  Rare Savannah Ecosystem 

Pine-Oak Savannah

A walk through Wasaga Beach Provincial Park dunes area takes you over 40 metre high dunes through an ecosystem more rare than the rainforests, pine-oak savannah.  This rarity was a common ecosystem 300 years ago.  The pine-oak savannah is a transition zone between the tall grass prairies and the forests to the east.  Subjected to agricultural development, urbanization, and industrialization less than one tenth of 1% remains of the original 13 million hectares of pine-oak savannah, an area that reached from here in Wasaga Beach to Texas.

A savannah is distinguished from woodland by having a tree canopy that covers less than 30% of the sky.  In a pine-oak savannah, scattered trees are surrounded by large open spaces filled with prairie wildflowers, grasses and shrubs, such as Big (Andropogon gerardi) and Little Bluestem (Andropogon scoparius), Indian Grass (Sorghastrum nutans), butterfly weed (Asclepias tuberosa), New Jersey Tea (Ceanothus americanus), wild bergamot (Monarda fistulosaI), and the nationally significant hill’s thistle (Cirsium hillii).  All of these species have special adaptations for surviving in these shade-free living conditions. Some of these adaptations would include waxy leaves that prevent rapid water loss, deep root systems or taproots, and seeds that germinate only after low intensity ground fires or they are exposed to heat from fire. 

In the past, pine-oak savannahs were maintained through fire.  Occurring approximately every 20 years, naturally ignited ground fires would sweep through pine-oak areas, preventing developing woodland from filling in the open prairie spaces.  Having deep taproots, many plants would survive the fires and flourish with newly released nutrients from burned oak leaves.  With flourishing plants following a fire, the entire ecosystem would benefit.    Hill’s thistle, a perennial measuring between 25 and 60 centimetres in height, has a habitat that includes dry, sandy or gravel soils that are prone to fire.  It also requires areas with low tree canopy cover, as it is a sun-loving plant.  Flowers usually occur in its third year of growth and its lightweight seeds are scattered by the wind.  Without the regular occurrence of fire however, these seeds will not reach the soil due to the accumulated leaf layer and thus unable to germinate.  Hill’s thistle is now considered to be a nationally rare species in Canada.

Hill's Thistle

Prescribed burn - June 8

Over the past century, fire prevention has taken a forefront in forest management over prescribed burns and fire control.  Due to this, leaf litter, brush, and shrub layers have accumulated in forested areas and filled in much of the open savannah.  Natural resource managers are now looking at the important role that fire must play in maintaining ecosystems.  They are now prescribing fire to re-open some of the overgrown forest and savannah ecosystems.

Wasaga Beach Provincial Park managers initiated a prescribed burn during the spring of 2004 as a part of the hill’s thistle recovery plan and to open the rare pine-oak savannah.  This prescribed burn covered an area of approximately 2 hectares.  Lasting a little over an hour, the fire successfully burned the ground and shrub layers within the burn site.  Park naturalists are conducting vegetation surveys to compare hill’s thistle and other prairie species following the burn.  Those areas, which were burned, will be compared to areas within the rest of the park.  To find out more information, please contact the Wasaga Beach Provincial Park office at (705) 429-2516.

Prescribed burn - July 5