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Community trees are important urban green spaces because they offer many ecosystem services necessary for environmental sustainability and human well-being. Understanding community trees’ ecological services is becoming increasingly important for efficient urban design and management as urban areas grow worldwide. The urban forest in Kamloops, British Columbia, Canada, plays a major role in the ecological resiliency and livability of the city. Nevertheless, there isn’t a thorough evaluation of the ecological services of community trees in Kamloops.  As urban areas expand, urban forests become increasingly vital for maintaining the quality of life for urban residents. They offer a multitude of ecosystem services, such as enhancing the urban environment (Goddard et al., 2009; Gómez-Baggethun and Barton, 2013; Morimoto, 2011), promoting physical, mental, and social well-being (Hartig, 2008; Maas et al., 2006; Mitchell and Popham, 2008; Mitchell and Popham, 2007), and generating economic advantages (Wolf, 2009). Urban trees are integral components of urban ecosystems, providing a wide range of ecosystem services that contribute to the well-being of communities and the sustainability of cities. These services include improving air quality, reducing urban heat island effects, mitigating climate change, enhancing biodiversity, and promoting mental and physical health among residents (Turner-Skoff & Cavender, 2019). To optimize these advantages via urban forest planning and management, urban planners, city managers, decision-makers, and even private citizens must comprehend and oversee the costs and benefits associated with urban forests during land use planning and urban development endeavors (Livesley et al., 2016; Vandermeulen et al., 2011). Certain species may offer more pronounced benefits (Chen et al., 2017; Grote et al., 2016; Xiao & McPherson, 2016), with variations observed even within a species. For instance, the benefits provided by a small street tree differ significantly from those of a large, century-old tree. Despite their scarcity, mature and old trees yield the greatest advantages (Lindenmayer, 2017; Lindenmayer & Laurance, 2017). As single organisms, large old trees disproportionately impact biodiversity and ecological processes by serving as habitats for various flora and fauna and facilitating crucial ecological cycles (Lindenmayer, 2017; Lutz et al., 2018). This factor should be considered when removing and compensating for large trees. Table 1 provides a detail description of the numerous ecosystem services urban trees provide to our community such as provisioning, regulating, maintenance and support and cultural.

Table 1: Ecosystem services provided by urban trees

Tree Characteristics of the Urban Forest

In the context of Kamloops, a vibrant city nestled in the picturesque landscapes of interior British Columbia, the urban tree canopy plays a significant role in enhancing the city’s livability and environmental quality. The entire city of Kamloops boasts a tree canopy covering 12% of its area. Recent residential developments exhibit notably lower tree canopy coverage compared to those established over two decades ago. Additionally, the city manages nearly 17,000 trees situated in parks and along boulevards. (Kamloops UFMS, 2022).

Kamloops is home to over 200 species of city trees, with the maple genus being the most prevalent, accounting for 25% of the distribution. However, within the maple genus, there exist numerous distinct species across the city.  Oregon crabapple, known for its resilience and adaptability, representing a notable portion of the tree cover and standing as one of the city’s defining species. Among the species present, Oregon crabapple is the most common, making up 7.8 percent of the urban forest. Norway maple follows closely, accounting for 7.4 percent, while Green ash rounds out the top three at 5.4 percent. Urban forests usually include a mix of native and exotic tree species, which often makes them more diverse than nearby natural landscapes. This higher diversity can protect the forest from species-specific pests or diseases, but it can also threaten native plants if certain non-native species are invasive. These invasive plant species tend to be hardy, adaptable, and reproduce quickly, with few natural enemies to keep them in check. These traits allow them to crowd out native plants. In Kamloops, about 55 percent of the trees are native to North America, while a significant portion, about 21 percent, originally come from Europe and Asia. The benefits trees provide are closely tied to the amount of healthy leaf surface area they have. In Kamloops, total leaf area of trees stretch across 140.5 hectares. To give a sense of scale, the total leaf area of these trees is equivalent to around 1.4 square kilometers. To put this in perspective, it covers about half the area of Vancouver’s Stanley Park, which is approximately 400 hectares. The trees with the most leaf area are Norway maple, Ponderosa pine, and American elm. The ten most significant species, based on their importance values, are shown in Table 1. These importance values (IV) are the summation of the percentage of tree population and leaf area each species represents.

Table 2. The most important species in Kamloops

Despite the recognized importance of urban trees, there is often a lack of comprehensive assessment and quantification of the ecosystem services they provide. In Kamloops, where urban growth and development continue to reshape the cityscape, there is a pressing need to evaluate the contributions of community trees to the urban environment. Such an assessment can inform evidence-based decision-making in urban planning and management, ensuring the preservation and enhancement of urban green infrastructure for current and future generations.

The questions this project hopes to answer include:

1. What is the value of the publicly provided trees (ecosystems) in Kamloops?
2. What is the value of ecosystem services per year of these trees?
3. What factors influence the value of the natural asset?
4. What are the spatial distributions of these ecosystems across different neighborhoods in Kamloops?
5. What is the valuation of trees across different neighborhoods in Kamloops?
6. What gaps can be found to improve the distribution of trees?

The objectives of this study are to:

1. Quantify the economic value of these ecosystem services to understand their importance in urban planning and management.
2. Identify spatial patterns of ecosystem service provision to inform targeted tree planting and maintenance efforts.