Prescribed Burns in High Park

Source: City of Toronto Precribed Burn Notices April 2008/2019

A prescribed burn is a deliberately set and carefully controlled low fire that consumes dried leaves, small twigs and grass stems, but does not harm larger trees. Prescribed burns are part of Urban Forestry’s long-term management plan to restore and protect Toronto’s rare black oak woodlands and savannahs.

High Park Prescribed Burn Advance Notice 2024

High Park Traditional and Prescribed Burn Final Notice April 9, 2024

Prescribed Burn 2015. Photo: Oliver Pauk

The Role of Fire

Since 2000 City of Toronto Urban Forestry has been using fire as a management tool to help restore and expand High Park native plant communities including the globally rare Black Oak savannah habitat. Different areas of oak savannah are burned on a rotating cycle. (See Summary of Burn Cycle by Management Unit.)

Prior to European settlement, fire played a pivotal role in maintaining the prairies, savannahs and oak forests that once extended across southern Ontario. This included deliberate burns set by Indigenous peoples as well as naturally occurring wildfires. (See Indigenous History of Today's High Park.)

Fire is an important factor in a healthy oak savannah as it helps to encourage and invigorate native species that have evolved to persist in fire controlled systems. Indigenous peoples used fire to maintain lush grasslands that attracted deer and other game for hunting.

Prairie plants including black oaks respond to modified site conditions following the burn, and grow more vigorously than they would have in the absence of the fire. Fire also works in reducing competition from some invading exotic species that are not adapted to a fire controlled ecosystem.

Successes of the High Park Burn Program

The natural fire cycle had been suppressed in High Park for over 100 years. With fairly regular fires occurring since 2000, large improvements have been observed in the distribution and health of native plant species in the park.

The initial goals for the prescribed burn program established in the management plan focused on enhancing the growth of native species while controlling exotic plant species. Special attention was also focused on targeting small rare plant communities existing in High Park in the hope of encouraging their natural expansion. Annual monitoring has shown that many areas in High Park are exhibiting large increases in native plant community patches, as well as a significant decline in some of the exotic species controlled by burning, such as garlic mustard.

High Park is home to many rare and important species that are thriving from prescribed burning. Species in the drier savannah areas are showing large success in expansion such as dryland blueberry, Indian grass, big bluestem, woodland sunflower, sky-blue aster, and a variety of goldenrods and sedges. Wild lupine populations have exhibited an immediate response, with increases in patch size as well as seed production.

In the beginning stages of the prescribed burn program, frequent burns were necessary to reverse the effects of the approximately 100 years of suppressed fire cycles. More frequent burning was required to set-back exotic invasive plants such as buckthorn and honeysuckle, allowing more light to penetrate into the savannah habitats.

Restoration of natural areas is an adaptive process. As the successes of the High Park prescribed burn program continue, the frequency and interval between burns are reevaluated and adjusted accordingly.

Prescribed burn management, in combination with native species planting and invasive species removal, will continue to be a valuable tool used in these rare habitats to ensure their longevity and proliferation.

Prescribed Burn 2022. Photo: Irene Wilk
Prescribed Burn 2022. Photo: Irene Wilk


Prescribed Burn Monitoring

Source: Urban Forestry, 2021

Prior to European settlement, the landscape was defined by Indigenous Peoples’ use of controlled burns to manage the landscape, coupled with naturally-occurring wildfires. Indigenous Peoples would use fire to clear the land for agriculture, to rejuvenate the quality and quantity of forage and medicinal plants, and to attract wildlife. This use of fire historically helped to maintain savannah habitat in the area on which High Park is located.

Prescribed burns were re-introduced to High Park by City of Toronto Urban Forestry in the late 1990s as a management tool. This began initially as demonstration plots and then as an annual operational program starting in 2000. Burns are designed to echo these historic controlled and natural fires and benefit native plants and animals by setting back invasive/exotic plant species, stimulating native plant regeneration, restoring wildlife habitat and returning nutrients to the soil.

Management areas within High Park are reviewed annually to monitor the species composition of the areas in relation to each site's individual goals. This review involves monitoring vegetation response to fire by looking at the presence and population size of both native and invasive species, as well as plant vigour, and informs which areas should be considered for the following burn period. Site review would also identify any site preparation needed prior to the burn taking place in order to achieve optimal results. For example, previous results have demonstrated the need to remove invasive shrub cover of a certain size in advance of burns to allow fire to carry through the sites to best encourage native species.

Immediately following the burn, staff evaluate the burn coverage by making site notes of impacts on protected areas, areas that had high heat points, and areas that did not burn as well. Some reasons why areas might not burn as well include dense leaf litter and/or shrub cover, moist conditions, and green non-native plant material. These observations are helpful when later evaluating the vegetation response to fire.

Prescribed Burn Monitoring, High Park, 2015. Source: City of Toronto

Sites are revisited after a few weeks and/or months following the prescribed burn to monitor plant regeneration and growth to determine progression of the site and plans for future work. This can include management of invasive species that are regenerating or moving into the newly disturbed areas, or identifying areas where the native seed bank is not regenerating and would benefit from planting locally sourced native plants.

Monitoring has shown increases in savannah species such as Wild Blue Lupine and young black oak seedlings following burns, as well as a reduction of some invasive species patches. Monitoring also enables changes to be made in response to site conditions – for example, creating insect refuges within a burn site to protect overwintering insects, or targeting removal of invasive plant species that fire cannot control.

Prescribed burning is an ongoing management practice that benefits the savannahs of High Park and is an integral element in protecting and preserving this valuable place.

Media coverage of past burns:

2024: BlogTOCBC

2023: Toronto Star "Toronto carries out High Park controlled burn as part of Black Oak protection". CBC: "Why is High Park on fire? How Indigenous-led prescribed burns protect the land".

2022: Toronto Star "Where there's smoke, there's renewal" online or the Pressreader version or this pdf of the print version. Global News City of Toronto conducts prescribed burn at High Park

2018: CBC News: High Park carries out 3 controlled burns with help of 'fire boss'

2017: Toronto Star article, Apr. 18/17

2016: Toronto Star

2015: NOW Magazine article with photos, April 16, 2015, CTV News article, April 2015, The Guardian photo highlight of the day, April 16, 2015

2013: Torontoist, blogTOToronto Star video

2012: NOW, blogTO, Torontoist

2011: Torontoist, blogTO, YouTube

Art Projects based on High Park Burns:

  • Alchemical Cinema: Land Breath Fire. Sound by Allison Cameron, in a controlled burn of the forest in High Park. Watch video
  • Frances Patella Smoke & Fire series

Person photographing the burn
Photographing the Burn. Photo: Karen Yukich

News & Sightings

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Source: City of Toronto Precribed Burn Notices April 2008/2019

A prescribed burn is a deliberately set and carefully controlled low fire that consumes dried leaves, small twigs and grass stems, but does not harm larger trees. Prescribed burns are part of Urban Forestry’s long-term management plan to restore and protect Toronto’s rare black oak woodlands and savannahs.

High Park Prescribed Burn Advance Notice 2024

High Park Traditional and Prescribed Burn Final Notice April 9, 2024

History of High Park’s Prescribed BurnsCity of Toronto Website – Prescribed Burns
Prescribed Burn 2015. Photo: Oliver Pauk

The Role of Fire

Since 2000 City of Toronto Urban Forestry has been using fire as a management tool to help restore and expand High Park native plant communities including the globally rare Black Oak savannah habitat. Different areas of oak savannah are burned on a rotating cycle. (See Summary of Burn Cycle by Management Unit.)

Prior to European settlement, fire played a pivotal role in maintaining the prairies, savannahs and oak forests that once extended across southern Ontario. This included deliberate burns set by Indigenous peoples as well as naturally occurring wildfires. (See Indigenous History of Today’s High Park.)

Fire is an important factor in a healthy oak savannah as it helps to encourage and invigorate native species that have evolved to persist in fire controlled systems. Indigenous peoples used fire to maintain lush grasslands that attracted deer and other game for hunting.

Prairie plants including black oaks respond to modified site conditions following the burn, and grow more vigorously than they would have in the absence of the fire. Fire also works in reducing competition from some invading exotic species that are not adapted to a fire controlled ecosystem.

Successes of the High Park Burn Program

The natural fire cycle had been suppressed in High Park for over 100 years. With fairly regular fires occurring since 2000, large improvements have been observed in the distribution and health of native plant species in the park.

The initial goals for the prescribed burn program established in the management plan focused on enhancing the growth of native species while controlling exotic plant species. Special attention was also focused on targeting small rare plant communities existing in High Park in the hope of encouraging their natural expansion. Annual monitoring has shown that many areas in High Park are exhibiting large increases in native plant community patches, as well as a significant decline in some of the exotic species controlled by burning, such as garlic mustard.

High Park is home to many rare and important species that are thriving from prescribed burning. Species in the drier savannah areas are showing large success in expansion such as dryland blueberry, Indian grass, big bluestem, woodland sunflower, sky-blue aster, and a variety of goldenrods and sedges. Wild lupine populations have exhibited an immediate response, with increases in patch size as well as seed production.

In the beginning stages of the prescribed burn program, frequent burns were necessary to reverse the effects of the approximately 100 years of suppressed fire cycles. More frequent burning was required to set-back exotic invasive plants such as buckthorn and honeysuckle, allowing more light to penetrate into the savannah habitats.

Restoration of natural areas is an adaptive process. As the successes of the High Park prescribed burn program continue, the frequency and interval between burns are reevaluated and adjusted accordingly.

Prescribed burn management, in combination with native species planting and invasive species removal, will continue to be a valuable tool used in these rare habitats to ensure their longevity and proliferation.

Prescribed Burn 2022. Photo: Irene Wilk Prescribed Burn 2022. Photo: Irene Wilk

Prescribed Burn Monitoring

Source: Urban Forestry, 2021

Prior to European settlement, the landscape was defined by Indigenous Peoples’ use of controlled burns to manage the landscape, coupled with naturally-occurring wildfires. Indigenous Peoples would use fire to clear the land for agriculture, to rejuvenate the quality and quantity of forage and medicinal plants, and to attract wildlife. This use of fire historically helped to maintain savannah habitat in the area on which High Park is located.

Prescribed burns were re-introduced to High Park by City of Toronto Urban Forestry in the late 1990s as a management tool. This began initially as demonstration plots and then as an annual operational program starting in 2000. Burns are designed to echo these historic controlled and natural fires and benefit native plants and animals by setting back invasive/exotic plant species, stimulating native plant regeneration, restoring wildlife habitat and returning nutrients to the soil.

Management areas within High Park are reviewed annually to monitor the species composition of the areas in relation to each site’s individual goals. This review involves monitoring vegetation response to fire by looking at the presence and population size of both native and invasive species, as well as plant vigour, and informs which areas should be considered for the following burn period. Site review would also identify any site preparation needed prior to the burn taking place in order to achieve optimal results. For example, previous results have demonstrated the need to remove invasive shrub cover of a certain size in advance of burns to allow fire to carry through the sites to best encourage native species.

Immediately following the burn, staff evaluate the burn coverage by making site notes of impacts on protected areas, areas that had high heat points, and areas that did not burn as well. Some reasons why areas might not burn as well include dense leaf litter and/or shrub cover, moist conditions, and green non-native plant material. These observations are helpful when later evaluating the vegetation response to fire.

Prescribed Burn Monitoring, High Park, 2015. Source: City of Toronto

Sites are revisited after a few weeks and/or months following the prescribed burn to monitor plant regeneration and growth to determine progression of the site and plans for future work. This can include management of invasive species that are regenerating or moving into the newly disturbed areas, or identifying areas where the native seed bank is not regenerating and would benefit from planting locally sourced native plants.

Monitoring has shown increases in savannah species such as Wild Blue Lupine and young black oak seedlings following burns, as well as a reduction of some invasive species patches. Monitoring also enables changes to be made in response to site conditions – for example, creating insect refuges within a burn site to protect overwintering insects, or targeting removal of invasive plant species that fire cannot control.

Prescribed burning is an ongoing management practice that benefits the savannahs of High Park and is an integral element in protecting and preserving this valuable place.

Protecting Wildlife

People have asked about the safety of the animals in High Park during the traditional and prescribed burn. The prescribed burn in High Park is a low-intensity fire as is appropriate for savannahs and woodlands. Flames stay very low and don’t reach mid-storey vegetation or the crowns of trees, so wildlife in trees are not affected.

Before ignition of any plot, City staff walk through in a line to induce any mammals to run to a place of safety adjacent to the burn site. Any active reptiles are carried to a place of safety. Any reptiles which have not emerged for the season are below the ground where they are safe from the fire (the heat from the fire does not penetrate far enough into the ground to reach turtle nests or snake hibernacula). Birds, like mammals, can move to a place of safety. If any cavity-nesting birds (e.g. wood ducks) are found during the sweep, extra care is taken around that tree. Dormant insects such as pollinators that may be in the leaf litter can’t move, so refugia (unburned portions) are left at the edges of burn sites (and adjacent to unburned sites) for recolonization when the burn site greens up.
 
Volunteers sweep the burn site for wildlife. Photo: Karen Yukich

In spring 2024, for the first time, community members from Indigenous Land Stewardship Circle, Turtle Protectors, and the High Park Stewards conducted a wildlife sweep of each burn site ahead of the City of Toronto’s own wildlife sweep of the sites. Several garter snakes were moved to safety and a rabbit was flushed and ran away.

Prescribed burn with figure on hill. 2018. Photo: Irene Wilk Prescribed burn with figure on hill. 2018. Photo: Irene Wilk Lighting the fire 2018. Photo: Irene Wilk High Park A to Z – F is for Fire

Friendly Fire on the Black Oak Savannah

by Kathleen Keefe

Gardening with Fire

It surprises many people to learn that fire is the best gardener possible for the black oak savannah. The indigenous people who first lived here knew this. They were great observers and students of nature and they noticed that after wildfires swept across the land, the plants grew better and attracted more wildlife. The native people learned that by intentionally and strategically setting fires in the springtime every few years, the vegetation and wildlife would flourish. For thousands of years, our black oak savannah depended on fire for health and survival.
It surprises many people to learn that fire is the best gardener possible for the black oak savannah.

The Price of Progress

When European settlers arrived, they built more permanent homes and communities. They designated land for farming, for logging, for business, for development and recreation. This was no longer a place to set or let wildfires burn across the landscape. The land, the people and their structures were protected by stopping all fires that could be stopped.For more than a hundred years, we prevented the beneficial age-old relationship between fire and savannah. During this time, the landscape suffered the loss of key species and healthy plant communities. New oak trees became scarce, less robust and less resilient.

A Happy Accident

Then a small accidental fire in a corner of High Park revealed what we had almost lost. Long-absent savannah grasses and wildflowers grew out of the blackened earth. Plants that had disappeared or had become scarce in the park showed us that their seeds were still in the soil just waiting for fire to return them to life!Only 1% of Ontario’s black oak savannah remains. Twenty-six hectares of that are in High Park and cover one third of it. A management plan to restore and preserve this incredibly special ecosystem has included regular prescribed burns since 2000. This is rejuvenating our black oak savannahs. An impressive 26 nationally rare plants now grow and support wildlife in High Park’s black oak savannahs.

How does it Work?

In the early spring, the first grasses and plants to sprout in the black oak savannah are not native to the ecosystem. They actually grow so quickly and thickly that they crowd out the later-sprouting native savannah plants. These early-sprouting plants from distant places have short roots and are not adapted to the savannah or fire. A carefully monitored, quick moving low fire burns away this barrier along with excess leaf litter.Meanwhile, the extremely long roots of the native savannah plants are not affected by the fire. When the black ash absorbs sunlight, it warms the soil and stimulates the growth of the native plants beneath. Up they come through the enriched soil into the light, ready to attract and support High Park’s wildlife.

History of High Park's Prescribed Burns

2024 – The traditional and prescribed burn took place on April 9 at 6 sites totalling about 9 ha. For the first time, volunteers took part in pre-burn “sweeping” of the burn sites to protect wildlife.2023 – After an Indigenous ceremony, 5 sites were burned on April 13 during a period of exceptionally hot dry weather. The total area burned was 9.9 ha.2022 – Extensive areas were burned this year and a new latest date was set – April 29 – due to frequent rains this spring. The total area burned was 10.23 ha.2020 & 2021 – Due to COVID-19 there was no prescribed burn in High Park.2019 – Following careful review of the proposed burn sites in High Park, it was determined that there will not be a burn for spring 2019. This delay will allow time for existing native plants to establish, oak regeneration and additional areas to be ready for burning.2018 – A prescribed burn in three areas covering a total of 6.6 ha was conducted on April 23, 2018. This was the latest date ever, with old snow still piled at the edge of the burn site.2017 – A prescribed burn was conducted at two locations in High Park on April 18, 2017, covering a total area of 4 ha2016 – No burn was conducted.2015 – A prescribed burn was conducted on Wednesday, April 15, 2015.2014 – No burn was conducted.2013, 2012, 2011 – Prescribed burns were conducted.
For a complete history of the prescribed burns in High Park, please see the Summary of Burn Cycle and Media Coverage listings below.

Summary of Burn Cycle by Management Unit 2000-2024High Park Management Unit Map

Media coverage of past burns:

2024: BlogTOCBC

2023: Toronto Star “Toronto carries out High Park controlled burn as part of Black Oak protection“. CBC: “Why is High Park on fire? How Indigenous-led prescribed burns protect the land“.

2022: Toronto Star “Where there’s smoke, there’s renewal” online or the Pressreader version or this pdf of the print version. Global News City of Toronto conducts prescribed burn at High Park

2018: CBC News: High Park carries out 3 controlled burns with help of ‘fire boss’

2017: Toronto Star article, Apr. 18/17

2016: Toronto Star

2015: NOW Magazine article with photos, April 16, 2015, CTV News article, April 2015, The Guardian photo highlight of the day, April 16, 2015

2013: Torontoist, blogTOToronto Star video

2012: NOW, blogTO, Torontoist

2011: Torontoist, blogTO, YouTube

Art Projects based on High Park Burns:

  • Alchemical Cinema: Land Breath Fire. Sound by Allison Cameron, in a controlled burn of the forest in High Park. Watch video
  • Frances Patella Smoke & Fire series
Person photographing the burn
Photographing the Burn. Photo: Karen Yukich

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