Trees provide numerous benefits in urban areas, including improving stormwater retention and filtration, removing gaseous and particulate pollutants from the air, sequestering atmospheric carbon, and ...reducing ambient temperature. However, trees also pose risks in urban areas. Trees growing near overhead electrical utility lines cause a large proportion of electrical power outages. To mitigate this risk, arborists frequently and sometimes severely prune trees near overhead utilities for clearance and to reduce the likelihood of failure. Ostensibly, urban trees distant from utility lines are not pruned as frequently or severely. This study aimed to (i) assess factors related to both individual trees and the sample populations of trees growing near and away from overhead utility lines, and (ii) determine whether those factors differed between the two groups. In total, 200 utility easement plots and 200 non-utility control plots were distributed in Eversource Energy’s distribution territories, encompassing 2361 trees in total. Diameter at breast height (DBH), crown height and spread, percent crown missing, percent twig dieback, and likelihood of failure were gathered for each tree in the study. These variables were compared individually among study groups, and used as inputs to calculate estimated ecosystem service delivery using USFS iTree Eco v6. Overall, trees in control plots were larger and delivered more ecosystem services, per tree, than trees in utility plots. However, on a population level, trees in utility plots were more populous and delivered more aggregate ecosystem services than those in control plots. Although the aesthetics of utility tree pruning is often debated, there were no differences in likelihood of failure ratings between trees in control and utility plots. These findings may help to frame trees near overhead utility lines, commonly seen as risks or eyesores, as valuable green infrastructure and community assets.
•Nearly all Massachusetts urban tree committees formed in the last 30 years, indicating the recency of urban forestry as a recognized profession.•Urban tree committee volunteers are typically ...motivated, passionate, and generally desire to work cooperatively with other organizations.•Successful urban tree committees work collaboratively with their local tree warden to advance the care of their community’s urban trees.•Municipal managers should attempt to provide urban tree committee volunteers with appropriate training opportunities and resources.•Municipal managers should demonstrate appreciation to urban tree committee members, to further encourage and solidify volunteer-engagement.
Citizen engagement through urban forest tree committee volunteer service may aid in providing essential experience, ideas, and skills that support municipal tree management. Using semi-structured, research interviews with tree committee (TC) representatives from across the Commonwealth of Massachusetts, this study addresses current knowledge gaps concerning the general composition, processes, and relationships of volunteer-led urban forest tree committees. Our findings indicate that TC representatives are typically motivated, passionate volunteers who generally desire to work cooperatively with the many associations, organizations, and agencies that comprise the local socio-political landscape. Our findings also indicate it is important that TC representatives make a sustained, concerted effort to work collaboratively with their local tree warden to advance the care of their community’s urban trees. Furthermore, it is also essential that municipal managers and decision-makers attempt to provide TC volunteers with appropriate training opportunities, resources, as well as demonstrate appreciation, to further encourage and solidify volunteer-engagement in urban forestry at the local level.
Urban forested natural areas are an important component of the forest and tree canopy in northeastern United States urban areas. Although similar to native forests in surrounding regions in ...structure, composition, and function, these natural areas are threatened by multiple, co-occurring biological and climate stressors that are exacerbated by the urban environment. Furthermore, forests in cities often lack application of formal silvicultural approaches reliant upon evidence-based applied ecological sciences. These include both urban- and climate-adapted silvicultural techniques to increase the resilience and sustainability of native forests in cities. With this in mind, we convened a group of urban forest practitioners and researchers from along a latitudinal gradient in the northeastern United States to participate in a workshop focused on co-developing long-term, replicated ecological studies that will underlie the basis for potential silvicultural applications to urban forests. In this article we review the process and outcomes of the workshop, including an assessment of forest vulnerability, and adaptive capacity across the region, as well as shared management goals and objectives. We discuss the social and ecological challenges of managing urban oak-dominated mixed hardwood forests relative to non-urban forests and identify potential examples of urban- and climate-adapted silviculture strategies created by practitioners and researchers. In doing so, we highlight the challenges and need for basic and long-term applied ecological research relevant to silvicultural applications in cities.
Green infrastructure is the aggregate of plants and green spaces in the urban landscape. This infrastructure provides many benefits that are becoming increasingly valuable as municipalities strive ...for urban sustainability. The value of the urban forest is an integral part of securing funding and support for urban forestry initiatives: the higher the value the more support is gained, and benefits accrued. According to available data from street tree inventories, most species that make up street trees in urban forests in the United States and Canada are broadleaf, deciduous species. Since many urban tree benefits are attributed to the tree canopies, benefits effectively drop to negligible levels during the leaf-off period. When a rain event occurs during this season, the canopy cover afforded by evergreen tree species, in concert with the canopy architecture and density of evergreen conifers will help to maintain canopy-dependent benefits. This paper investigates the role that conifers play in increasing the canopy-dependent ecosystem services of an urban forest and the unique role they play in increasing the stability of the urban forest through diversification.
•Compiled a database of arboricultural safety standards among 29 countries•Searched for common safety categories in 29 countries with at least 1 ISA component•In 82 % of countries, an industry ...standard was used•From 14 unique standards, we identified 90 safety categories•Of 90 safety categories, 19 were in all standards and 20 were in all but 1 standard
Arboricultural safety standards exist in some countries, but it is unclear how many standards exist, how they compare to one another, and whether (and how many) countries share standards. To address these gaps, we obtained and analyzed arboricultural safety standards from 29 countries. We determined which safety categories were included in each standard to highlight frequently and infrequently included categories. We computed the proportion of all safety categories included in each standard, and we compared standards to determine their similarity with one another. Among 29 countries, 14 unique standards exist. Of 90 safety categories gleaned from the standards, 19 were included in all standards and 20 were included in all but 1 standard. Standards in Hong Kong, Poland, Singapore, Spain, and Sweden included at least 90 % of 90 safety categories. Our findings can be used by safety committees around the world to develop or revise local standards; they may also be used to help develop an international best management practices guide for safety.
In most urban areas, residents have regularly occurring experiences of the trees around them. They interact with trees based on those experiences, as well as their own personal values, priorities, ...and identities. Whether those interactions with trees are active or passive (and whether or not they are conscious interactions), it is necessary to understand them in order to gain a more detailed picture of the urban forest. Qualitative research, and interviews specifically, are an important tool for developing this knowledge as they can uncover a deep understanding of an individual’s values, experiences and perspectives; build relationships between researchers, practitioners and community members; and support the inclusion of diverse and nontraditional perspectives in the pursuit of procedural and recognitional justice in urban forestry. In order to understand how and why interview methodology is being used to understand human-tree relationships in the built landscape, we employed PRISMA methodology, multiple screening phases, and NVivo qualitative coding software to identify and analyze 112 manuscripts that employed interviews in their study of human perspectives of, and interactions with, built-landscape urban trees. Findings show that interview methods are a relatively new introduction to urban forestry research, and that they have been primarily utilized to learn about: (1) Civilian perspectives/perceptions, sometimes with regard to diverse groups and those historically underrepresented in urban forestry; (2) Civilian participation/decision-making with regard to activities on their own property and volunteer activities in the community; (3) Urban forest manager and arborist perspectives and decision-making; and (4) Stakeholder collaboration – among government entities, NGOs, businesses and volunteers. Most studies (particularly those based in the Global North) prioritized the perspectives of decision-makers over community members, which highlights the need to find new ways of bringing different voices into urban forestry research and practice.
The first state-legislated and mandated municipal urban forestry officials in the United States were tree wardens. Massachusetts state law enabled municipalities to appoint tree wardens first in 1896 ...and mandated their appointment beginning in 1899; five other states passed similar legislation shortly thereafter. These municipal officials have jurisdiction over most, and sometimes all, public trees in the municipality they serve. This study used a structured mail survey to explore ways tree wardens acquire professional information, what modes of learning they prefer, how they interact with their communities, and what urban forestry tasks they do. Results suggest that New England tree wardens acquire information in several ways, including the Internet, yet prefer traditional outreach education tools such as workshops and conferences, especially those that involve more than one speaker, informational handouts, and both indoor and outdoor lectures and exercises. Tree wardens value highly interacting with other tree wardens and depend on peers and colleagues for information and assistance in decision making. They also value other organizations, such as the Cooperative Extension System, state forestry agencies, and state tree warden associations, for information. Results further suggest that public safety is their primary motivation and that they spend most of their time on associated tasks such as risk tree assessment and removal. They recognize the value of tree replacement and certain urban forestry planning practices such as tree risk assessment and inventories. Tree wardens place less importance on municipal shade tree ordinances and shade tree or urban forest committees or commissions. It is recommended that people and organizations responsible for tree warden education conduct activities that bring tree wardens together frequently and combine social and educational activities and emphasize traditional outreach education delivery systems.
To build deeper knowledge regarding urban forestry issues and familiarity with programming audiences, a multi-year needs-assessment was conducted by initiating qualitative stakeholder research ...interviews with professional urban foresters (i.e., tree wardens) and volunteer urban tree committee chairs. An objective of this exercise was to inform the implementation of relevant university-based continuing education (i.e., extension) opportunities, that led to the development of deliverables that included online urban forestry programming, the initiation of an urban tree committee census, and the development of a street tree selection guide. Findings indicate that qualitative stakeholder research interviews are a reliable needs assessment methodology and have widespread applicability among education professionals.
Inventories of urban tree populations and affiliated analysis software are valuable, contemporary tools in use by municipalities across the globe. While software that allows users to explore the ...values and benefits of discrete urban tree populations may be readily available, capacity to model and project tree growth is limited. Using existing urban street tree inventory data from Amherst, MA (USA), a generic platform for tree growth modelling was developed to be implemented by the user at the source code level, called "Xylem". Agile programmes like this provide a fast-working, extensible platform to generate tree growth projection data that can be delivered efficiently to the end user. The Amherst case study offers an example of how programmes written in Python 2.7 have application and can be readily customisable, to add value to existing tree inventory data.
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