The city of Toronto encompasses an area of 630 square kilometres with a population of 2.8 million. Urban forestry is a branch within the division of parks, forestry and recreation, responsible for providing services of maintenance, planting and protection of the urban forest. These services are delivered to areas including parks and natural open spaces as well as streetscapes.
Urban forestry's policy and planning section provides support to the division in environmental policy development, asset and work management administration, council reporting and other services. Approximately 350 staff work in the Toronto urban forestry division.
Forest health care is a service that is provided as part of urban forest maintenance. Forest health care practitioners respond to queries from residents about city tree health concerns, many of which are aesthetic in nature, but some of which are real health issues.
The forest health care group at the city also proactively develops and manages programs for pest management, from pest surveillance to treatment, monitoring and communication. This small team of seven people has developed tools that are required for pest management. They have a history of working with partners such as the Canadian Forest Service, the Canadian Food Inspection Agency, the Ministry of Natural Resources, other municipal groups, university researchers and other agencies. These partnerships have been essential in supporting the management of forest pests in Toronto.
Native insects and diseases play an essential ecological role in Canada's forests. However, native and non-native insects and diseases can become significant pests when infestations are so severe they destroy or damage large areas of forest or infest Canadian forest products that are bound for export. Mountain pine beetle, spruce budworm, European gypsy moth and Dutch elm disease are examples of well-known forest pests that have led to significant economic impacts on Canadian forests.
The City of Toronto currently invests approximately $2.5 million annually in forest pest—insect and disease—management programs as part of an overall forest management budget of $68.7 million. Between the years of 2010 and 2018 the City of Toronto invested over $70 million to manage the emerald ash borer problem.
In addition to the ongoing pest management programs and extension services, we perform surveillance for pests that represent a future threat including the hemlock woolly adelgid, sudden oak death, oak wilt, thousand cankers disease and butternut canker. The population of trees associated with these pests in Toronto is small, an estimated 2.5% of the total tree population in Toronto, but the impact associated with the loss of native tree species diversity and the associated flora and fauna communities is of great concern.
There is a social connection to trees that elicits emotions that go far beyond what industry, biologists and real estate agents might see in the value of a tree. The black oaks in High Park, the red oaks in Toronto's neighbourhoods such as Baby Point, the Beaches and Moore Park, and the hemlocks of Toronto's ravines all have a value that is not easily described in environmental or financial terms.
The rally to save the oak tree on Coral Gable Drive in North York is testament to the emotional connection that some residents develop with trees. Urbanites as well as rural landowners are significant stakeholders of Canada's forests, and it's important that we support forest health programs, particularly surveillance and education in all communities, especially where local taxes are insufficient to provide these services.
The federal government through the Canadian Food Inspection Agency has a vital role in the establishment of eradication protocols. Toronto has worked closely with CFIA through the 14 years of Asian long-horned beetle eradication as well as in the early days of emerald ash borer infestation. Toronto participated actively in surveys, and we have also supported research activities to develop early detection tools and to enhance the knowledge base of host dynamics.
When the Asian long-horned beetle was first introduced to Toronto, very little was known about which host species the beetle would infest and successfully breed in. As a result, many trees were cut unnecessarily because they were considered potential pest hosts. Now after years of collaborative research, we have a much better understanding not only of the host species, but also of the dispersal patterns and the best way to complete early detection surveys, as well as how to manage an effective survey team over a long period of time.
Toronto supported this research by providing labour and equipment to collect samples and providing space for a rearing facility. The partnership was mutually beneficial in supporting the evolution of the pest eradication program, and will result in a more effective, less costly program of eradication if and when a new infestation is discovered in Canada.
A scientist expert with the Canadian forestry service led a team of science and subject matter experts from Natural Resources Canada, CFIA, MNR, the U.S., universities, as well as municipalities and conservation authorities to guide the eradication program. It proved to be very effective model to guide the eradication of Asian long-horned beetle.
While the role of the Canadian Food Inspection Agency in defining eradication protocols is clear, the transition from eradication to pest management is not. In the case of the emerald ash borer, there was a lack of support for management activities on the level of guidance as well as funding. There's a clear need for more effective delivery of training and management plans to address a range of pests, plans that can be applied to all forms of land type, including Crown land, provincial or national park and conservation land, municipally owned land and private land. Currently, the mandate for defining such management falls to the landowner. In some cases, landowners have qualified staff to assist in developing site-specific plans, but in other cases this expertise is lacking. The management is left to service providers, such as arborists and forest service companies hired on contract, or to “do it yourself” property owners.
There is a case to be made that government could provide more guidance for management activities to direct pruning, tree removal or replacement, as well as disposal. As an example, seasonal pruning restrictions would help reduce the spread of oak wilt, yet documents from the government agencies are primarily focused on identification. Ongoing training opportunities should be available and delivered regionally in workshops or via web-based services.
The Canadian forestry service has provided essential support for the development of pest control products, including TreeAzin and Bacillus thuringiensis, both of which are used by the City of Toronto [Technical difficulty—Editor] and gypsy moth. It's important that the Canadian forestry service continue to support the development of such products.
Forest pests do not recognize municipal, provincial or international boundaries. Federal government scientists are well positioned to coordinate research for pests that are considered a high risk to Canadian forests. The development of science teams is critical in the early stages of pest management to make recommendations for effective prevention and early eradication programs. These teams can also inform management plans that will take effect if eradication is not successful or within regulated areas that are very large.
The science committee that was formed to manage ALHB was extremely effective in elevating the knowledge through support for targeted research and collaborative management. This model is one that should be repeated in advance of new pest introductions. The federal and provincial government experts could lead a group of subject matter experts to collaborate on developing pest management and guiding required research programs.
The importance of collaboration cannot be overstated. Municipalities are not well positioned to lead such collaborative groups, although we do contribute practical knowledge, provide arboricultural services to facilitate research, and assist in programs such as surveillance or engaging the public in educational initiatives. It's critical that different levels of government work together.
With regard to changing weather, our future weather is projected to change. A Toronto report called “Toronto's Future Weather and Climate Driver Study” identified estimated change from the period 2000 to 2009, 40 years into the future. They identified things like maximum precipitation increase in one day from 66 millimetres to 166 millimetres; maximum daily temperature increases from 33°C to 44°C; number of days with temperatures less than -10°C changing from 25 to zero days; and number of days with temperatures greater than 24°C changing from 10 days to 180 days, meaning that significantly more air conditioning will be required.
While it's recognized that the impact of these changes will be significant to Toronto residents, the impact on forest health is largely unknown. As an example, the population of gypsy moth has been controlled naturally in the past, when extreme cold temperatures in the winter months contributed to winter mortality of egg masses. In future, the temperatures will not be cold enough to cause mortality, and forest health practitioners will rely on biological controls or continued spray programs to control the pest.
It's important to support research into predicting, for example, pest movement, expanded host ranges, and changes in pest and host dynamics. In times when there is political pressure for reduced government regulation, it is important that the federal government retain programs for research. In a time of significant ecological and climate change, we need to develop tools for the management of new pests. It's also important to support the approval of new technologies, such as the use of drones to apply ultra-low volume spray.
I recently read in the Globe and Mail an article that referred to our inability to perceive incremental change as one of humanity's greatest weaknesses. Biologists identify that each generation grows accustomed to a diminished ecosystem. Our concept of biological abundance is constantly being downgraded without anyone noticing. My generation has never seen American chestnut. My kids will probably not remember Canada's ash trees, and they will only remember the oaks and squirrels that once dominated their outdoor universe.
If we don't remember what's being lost, such as camping under the hemlocks in Algonquin Park, will we recognize the importance of protecting the landscape after the hemlocks die, to ensure that the site is able to recover to a future forest? History tells us that most people will not, unless we help them to see the changes over time. It's only through effective collaboration and support for environmental education that we can help Canadians to appreciate the remarkably diverse elements of the natural landscapes that exist in Canada.