Invasive Species Threatening the York Regional Forest
An exploration of the non-native invasive plants, trees, and pests that are disrupting the region.
The Story of the York Regional Forest
Explore the York Regional Forest, past and present, to learn how healthy forest species thrive, the species that threaten forests, and how we can all take action to protect local forest health for the future. Scroll down to start your journey!
Past to Present
What did European settlement look like 150 years ago in York Region?
150 Years ago
The area was primarily hardwood dominant, older climax forest. The land is located on the traditional territories of the Wendat, the Haudenosaunee, and the Anishinaabe peoples, whose presence in York Region continues to this day. Try the interactive historical mapping tool to learn What York Region Looked Like in 1860 .
Early settlers
Settlers clearcut forests for farming.
Soils couldn't support intensive agriculture
The intact forests were key to soil stabilization, therefore, soils could not support intensive agriculture, and at the time there was no soil testing. The root systems of trees had kept the soils in place. With deforestation, the soils were no longer stable which resulted in wind erosion, also referred to as the Blow Sands Era.
1920's to 1960's reforestation
Rows of pine trees (red and white) were planted to stabilize the soils. These pine species are tolerant of nutrient-poor soils and act as nurse trees to kick-start the nutrient cycle.
Slow regrowth
With monoculture plantations, the nurse tree system has been slowly adding nutrients back to the soil, adding shade and creating microcosms that help other species grow; therefore, the forests are able to support more diverse species.
The York Regional Forest
The York Regional Forest was established in 1924 by the Province of Ontario but was originally called the York County Forest. In 1941, the province handed over the ownership and management of the Forest to York County, now called York Region.
The York Regional Forest continues to grow today
As time has passed, natural forest succession has taken place. Many areas of the York Regional Forest are starting to represent the forests that once existed prior to settlement. The forest now supports greater biodiversity and benefits both ecological and human health. Explore trails for all interests and abilities with the Recreation and Culture map .
Current threat: invasive species
The Forest faces threats from invasive non-native species such as the dog-strangling vine, a plant originally from Eastern Europe. To learn more about this destructive species, scroll further down below.
A hopeful future
Each year more forest visitors are contributing to environmental monitoring efforts in their community: flagging and preventing the spread of invasive species, tracking biodiversity, and celebrating healthy forests for all. Learn how you can help out further down below.
Slide between the photos to compare the York Regional Forest view from circa 1960, a period of extensive agriculture, to present day reforestation.
Slide between the photos to see the how the forest looked in the 1960s, to now!
Slide between the photos to compare a healthier, more diverse forest (left) compared to a monoculture of the dog-strangling vine (right). Dog-strangling vine happens to flourish in pine plantations as the tree canopy lets in the perfect amount of light.
Healthy forests support clean air and water, help protect our communities from climate change, and host a wide range of species throughout all seasons of the year.
Spring
Summer
Fall
Winter
A Closer Look at Invasives
Invasive Species are defined as harmful alien species whose introduction or spread threatens the environment, the economy, or society, including human health. (Government of Canada, 2004).
Ontario's definition of an invasive species may include species native to Ontario, that have been introduced to a new geographic region due to human activity. Species may be considered invasive if their introduction or spread can be linked to our changing climate. (Ontario Ministry of Natural Resources, July 2012. Ontario Invasive Species Strategic Plan)
Take a closer look at invasive species in York Region and scroll through to learn more about the invasive species threatening the Forest and species that can potentially threaten the York Regional Forest in the future.
Dog-strangling Vine
This plant is a serious concern for the conifer plantations in the York Regional Forest.
- Forms dense patches that overwhelm and crowd out native plants and young trees.
- Prevents forest regeneration.
- Leaves and roots can be toxic to forest animals.
- Changes soil chemistry, making it less hospitable for native plants and more suitable for its own spread.
The seeds of this plant can be carried by the wind over long distances, and it is finding its way into our backyards and natural areas across York Region.
Dog-strangling Vine in York Region
The spatial extent of dog-strangling Vine is all across York Region! Data is submitted on both iNaturalist (green dots) and EDDMapS (orange dots) platforms.
Emerald Ash Borer
First discovered in York Region (Vaughan) in 2008. By 2015, the pest was observed throughout all of York Region.
In the York Regional Forest:
- There are around 65,000 mature ash trees in the York Regional Forest.
- Approximately 13,000 ash street trees have been removed to-date.
Emerald Ash Borer
- Emerald Ash Borers are known for the S-shaped path and D-shaped entry holes they create in ash trees.
- Up to 99% of all ash trees are killed within 8-10 years once the beetle arrives in an area.
Emerald Ash Borer in Ontario
Student volunteers now report emerald ash borer observations through EDDMapS (orange dots), and more following EcoSpark training. Additional observations are submitted by community volunteers through iNaturalist (green dots) all across Ontario.
Asian Long-horned Beetle
First detected in York Region (Vaughan) in 2003 and quickly deemed eradicated by the governing authorities. But, it was rediscovered again in 2013 in Mississauga.
- All infested and host trees within 800m of the initial find were removed and destroyed to prevent the spread.
- Detection surveys continued until 2020 when it was declared eradicated.
- The re-detection in 2013 was thanks to a citizen scientist who knew who to contact when they discovered the beetle. This is a great example of early detection and rapid response.
Look-alikes for the Asian Long-horned Beetle in York Region
The white-spotted sawyer beetle is native to York Region and throughout Ontario.
Asian Long-horned Beetle in North America
This species has not been recorded on iNaturalist (green dots) or EDDMapS (orange dots) in Canada but there are a few observations submitted in the East Coast and West Coast of the United States.
York Region residents should be on the lookout for this species and report potential sightings, using the tools mentioned below.
Garlic Mustard
Can invade relatively undisturbed forests.
Once established, it can displace important native plants.
- This plant can hinder the growth of important native plants by altering the soil's chemistry.
- The altered soils prevent native plants from accessing important nutrients to stay healthy.
Threatens several of Ontario’s species at risk.
Garlic Mustard in York Region
Garlic mustard is an invasive species observed all over York Region by iNaturalist users!
Hemlock Woolly Adelgid
- Tiny sucking insect that attacks and often kills Eastern Hemlock trees.
- Nymphs feeds on tissues of tree’s twigs.
So far, this species has been discovered in:
- Etobicoke 2012
- Niagara Gorge 2013, 2014, 2015
- Wainfleet Township 2019
- Fort Erie 2020
Hemlock Woolly Adelgid in North America
Few observations of this species have been recorded in Canada on iNaturalist (green dots) and EDDMapS (orange dots). The majority of the observations are recorded in the East of the United States.
Spotted Lanternfly
Spotted lanternfly was added to Canada's regulated pest list in 2018 in an effort to prevent the introduction from infested areas in other places in North America. It has not yet been seen locally in York Region, but the public should keep an eye out and submit a photo if observed, using the tools below.
Spotted Lanternfly in North America
The spotted lanternfly has been observed primarily in the East Coast of the United States by both iNaturalist (green dots) and EDDMapS (orange dots) users.
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Success Stories
Take a tour of sustainability success in action! In Fall 2020, a team of Environmental Technology students from Fleming College worked with EcoSpark to assess both aquatic and terrestrial biodiversity in the York Regional Forest Tracts. Their data is shared with York Region staff and the public via databases including the Ontario Benthic Biomonitoring Network, iNaturalist, and EDDMapS. In addition to students from Fleming College, students from York Region District School Board have also worked with EcoSpark to share their findings via School Watch programs.
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1
Hollidge Tract student researchers
Students explored The Hidden World Beneath Your Feet in York Regional Forest Hollidge Tract to raise awareness about protecting biodiversity.
Terrestrial surveys for birds, plants, and other biota recorded the presence of native and invasive species. Students learned how reporting observations informs stewardship.
A stream study including benthic biomonitoring, physical, and chemical data provided a snapshot of aquatic biodiversity and water quality.
2
Happy Valley Tract surveyed
In order to help York Regional Forest visitors document and celebrate their nature observations, students designed Connecting to Your Senses in Ontario's Greenbelt .
The Happy Valley Tract was also surveyed with citizen science protocols to record incidental biodiversity observations and forest and stream health.
3
Bill Fisch Forest Stewardship and Education Centre
This centre provides an opportunity to host a variety of events, including outdoor educational programs like Nature's Classroom which promote and support the use of citizen science tools including EDDMapS Ontario. For more information on Nature's Classroom, visit www.york.ca/outdooreducation
4
Milliken Mills High School
Students at Milliken Mills High School (YRDSB) participated in EcoSpark's School Watch program. They learned about plant diversity and invasive species by studying how seeds spread on their school grounds.
5
Richmond Green Secondary School
Students from Richmond Green Secondary School participated in EcoSpark School Watch Virtual program. After learning the benefits of biodiversity, the class was provided with native plant seeds to support biodiversity in their gardens in York Region.
This map is a visual example of how public participation helps to track the distribution of invasive species
The York Regional Forest utilizes this information to comprehend how invasive species occur in our region.
- This type of information is useful for:
- Rapid responses
- Managing and tracking species
- Early mitigation
- Prevention of harmful introductions
Report Sightings
You can help by spreading awareness instead of invasives.
If you encounter an invasive species, make sure to report it!
Handy tools such as the iNaturalist app provides useful information about all plants and wildlife species on the go. By using these free resources while exploring nature, you can learn which species are native and which may be causing harm. Your photos of nature can help the entire community enjoy and protect local biodiversity!
EDDMapS Ontario is a platform used for tracking invasive species in the province. The data they collect helps to detect and identify invasive species early, and better understand their distribution.
Start by clicking the REPORT SIGHTINGS button and proceed to sign-up and create an account.
Fill out your information! This way, you can keep track of all your reported sightings.
You will then be prompted to identify the species you would like to report.
Be as detailed as you can! This helps the site narrow down and identify the species you are reporting.
Photo(s) courtesy of: York Region and Aileen Barclay
Now you're the scientist!
By reporting the invasive species you encounter when visiting the York Regional Forest or from any other green spaces in your community, you help EddMapS with the tracking and identification of forest invaders.
Nature observations shared with the EcoSpark iNaturalist Project Page are crucial for learning about and promoting local biodiversity!
