Multipurpose census methodology to assess urban forest structure in Hong Kong

Fulltext link: http://joa.isa-arbor.com/request.asp?JournalID=1&ArticleID=3073&Type=2Surveys of urban forests in the compact city environment of Hong Kong were initiated in 1985 and regularly updated thereafter. Roadside trees were evaluated first in a tree census and reported in this article followed by urban parks, public housing estates, and special habitats such as old stone walls or special specimens such as heritage trees. The survey method aimed at collecting comprehensive data to echo both tree conditions and tree-environmental interactions. Detailed information was gleaned, with the help of well-trained assistants, on tree sites, tree growing space, tree structure, and tree defects and disorders. A field record form was designed, pilot-tested, and refined to solicit responses to multiple choices or direct measurements to minimize subjectivity and errors in data recording and entry. The study also identified potential planting sites, registering suitability for tree growth, site characteristics, and dimensions. Data fields were designed to be quantitative or convertible to ordinal ranks to facilitate statistical analysis. Locations of trees and planting sites were marked on large-scale maps to permit spatial analysis. Besides statistical analysis, community ecology attributes and custom-designed indices were used to assess urban forest structure. The multipurpose method could be appropriately adjusted for use in other compact city areas. © 2008 International Society of Arboriculture.link_to_subscribed_fulltex

Street Tree Resource Evaluation and Education Trust (STREET)

An educational and applied research project, Street Tree Resource Evaluation and Education Trust (STREET), was conducted to train Master Gardener volunteers to identify and inventory Bucyrus street trees, to educate city government and citizens on street tree benefits, to secure funding and city approval for new street tree planting, and to compare citizen and landscape contractor tree planting by tree planting depth. Outcomes of STREET included: identification and inventory of 1,797 street trees, grant funding of $5000, 194 new trees planted, and citizen tree planting depth higher than tree professionals

Utilizing Inventory Data and Public Opinion to Develop an Urban Tree Management Plan for Oak Ridge, TN

Proper management by a trained urban forester is essential for the health of urban trees, due to the adverse growing conditions they face. Unfortunately, many cities do not have the luxury of employing an urban forester for various reasons, which is the case for the City of Oak Ridge, TN. This study utilized inventory data of the street trees, park trees, and trees surrounding the municipal complexes in Oak Ridge, as well as evaluated park visitor satisfaction in three of the city parks through the use of a survey to aid in the development of an urban tree management plan. Understanding what plant species are growing within cities and the benefits associated with those trees are only small parts of proper urban tree management. Additionally, assessing citizens’ attitudes towards the benefits of vegetation in areas such as city parks is important, due to the fact that the purpose of these areas is public enjoyment. The total urban tree inventory was completed over two years and consisted of 2,442 trees (H’ = 3.55). The inventory data was utilized to calculate benefit estimations for the city in the software program i-Tree, producing a total $133,796 in benefits, and a benefit-cost ratio of 0.90. For the park visitor survey, a total of 263 people participated in the survey among the three parks. Survey results revealed that for the two future management factors produced (future planting efforts and future tree care) there was a significant relationship for both factors with attitudes toward trees as well as a significant relationship between future planting efforts and visitor personal preference of park aspects. The inventory data, i-Tree benefit estimations, and survey results were used to aid in the development of a 10-year management plan for the city of Oak Ridge. This management plan contains 1) specific guidelines for proper tree care, 2) planting protocols, 3) strategies to manage pest or disease outbreaks, and 4) guidelines for raising public awareness of the urban forest through citizen engagement outreach programs. The management plan will be completed and presented to the city of Oak Ridge in September of 2015

Arbor Assets: The ROI of Campus Urban Forests

Values at Work Series: Facilities Services developed our core values of Service, Integrity, Teamwork, Excellence, and Stewardship (collectively referred to as SITES) based on the way we approach our work. Our values can be found throughout our areas of services in many ways.Through a series of articles, the Values at Work Series is devoted to providing a closer look at how our values are hard at work. Each article focuses on an area of service and how that group incorporates our values in a significant way. We are proud of our employees who continue to serve as an example of “walking the talk” every day.The University of Texas at Austin’s extensive grounds are home to a vast array of tree canopies lumbering across the campus’ urban landscape, along with a variety of flora native to the sunny skies of the Southwest. From the towering branches of the massive Battle Oaks to the fruit-bearing orchard adjacent to Waller Creek, these trees bring a multitude of benefits to everyone in the university community. Yet when UT Austin’s arborists discuss the benefits stemming from our urban forest, their conversations sound almost more like something that would take place in a classroom for the McCombs School of Business. Terms like return on investment (“ROI”), “valuation,” “asset appreciation” and “green infrastructure” can be heard from the Landscape Services conference room in the Facilities Complex. That’s because the conversation among professional arborists at universities has evolved as urban forestry programs have evolved.Facilities Service

Carbon Accounting in the Arboriculture Industry; Reduction of Greenhouse Gas Emissions from Tree Surgery

Increasing atmospheric concentrations of greenhouse gases (GHG) have been directly attributed to human activity; burning fossil fuels, land use change e.g. deforestation and energy production. Current practices in arboriculture rely heavily on fossil fuel based equipment to maintain trees in urban areas; removing carbon sinks (trees) and emitting CO2 during management practices. Therefore, it has been suggested that the arboriculture industry may make a disproportionately large contribution to GHG emissions when compared to the size of the sector. The study sought to identify the contribution of arboriculture to anthropogenic (GHG) emissions and provide recommendations for reduction. Assessment of the industry was achieved using a case study approach of a tree surgery company Down to Earth (DTE) based in Sevenoaks, Kent. The structure of CO2e (carbon dioxide equivalent) quantification methods followed the top-down approach - BS ISO 14064:2006; using secondary data to measure CO2e emissions and primary data for assessment of daily activity optimisation. The results, based on project boundaries included direct emissions from sources owned or controlled by the company – 101.2 tonnesCO2e yr-1, indirect emissions from energy use – 5.2 tonnesCO2e yr-1, and indirect emissions owned or controlled by other organisations – 98.9 tonnesCO2e yr-1. Results suggested that the arboriculture industry releases 7 times more CO2e emissions yr-1 than other similar-sized service sectors. This was mainly attributed to the use of plant and heavy-duty vehicles and the removal of carbon storing biomass. The study suggested that changing current practices could reduce GHG emissions from arboriculture by between 12% and 18%. In 2011 DTE provided 719 tonnes of wood chip to a renewable electricity generation plant, substituting coal use avoiding the release of 1,062 tonnesCO2e. Therefore, although arboricultural activities emitted 235.50 tonnesCO2e, this figure was more than offset (825.58 tonnes CO2e) by the avoided emissions achieved in power generation. By providing a renewable feedstock for the generation of electricity it is suggested that the arboriculture industry may, in the future, achieve carbon positive status and its practices seen as the management of a renewable energy crop

SOCIO-POLITICAL AND NATURAL-ECOLOGICAL FACTORS INFLUENCING URBAN FOREST MANAGEMENT IN MASSACHUSETTS

The management of urban forest systems is a complex interaction of social-ecological elements where biophysical factors interact with social aspects including policy decision-makers, managers, and municipal and private-sector employees. In the New England states, tree wardens are the local officials responsible for the preservation, maintenance, and stewardship of the public trees of a municipality. In-person qualitative research interviews were conducted with 50 tree wardens throughout Massachusetts to understand position duties, responsibilities, and professional challenges at the community-level. Qualitative research interviews were also conducted with chairs from 13 volunteer urban tree committees across Massachusetts. The value of employing qualitative methodologies in urban forestry, such as research interviews, as a mechanism to inform Extension professionals of stakeholder needs was also explored and further defined. Clearly emergent themes were identified from interview data and explored through analysis and comparison with existing literature. Tree wardens are typically housed in a municipal department, routinely interact with a number of local organizations, including urban tree committees, and are concerned about emergent plant health issues of importance including Asian longhorned beetle (Anaplophora glabripennis), emerald ash borer (Agrilus planipennis), and hemlock woolly adelgid (Adelges tsugae) (HWA). Since eastern hemlock (Tsuga canadensis) is one of only four native coniferous trees of ornamental importance in the Northeast U.S., and coniferous trees are notoriously underplanted in the urban environment, the ecology and natural history of its native and invasive insect and disease pests were reviewed in detail. These included HWA, elongate hemlock scale (Fiorinia externa), and shoestring root rot (Armillariaspp.). The use of pest resistant plant material – a strategy known to arborists and urban foresters as employing host plant resistance (HPR) – with applicability of HWA-resistant hemlock trees as potential substitutes for eastern hemlock plantings was explored. It was determined that HWA-resistant Chinese hemlock (Tsuga chinensis) would make a suitable surrogate ornamental planting for eastern hemlock in the urban environment

Biological, Social, and Urban Design Factors Affecting Young Street Tree Mortality in New York City

In dense metropolitan areas, there are many factors including traffic congestion, building development and social organizations that may impact the health of street trees. The focus of this study is to better understand how social, biological and urban design factors affect the mortality rates of newly planted street trees. Prior analyses of street trees planted by the New York City Department of Parks & Recreation between 1999 and 2003 (n=45,094) found 91.3% of those trees were alive after two years and 8.7% were either standing dead or missing completely. Using a site assessment tool, a randomly selected sample of 13,405 of these trees was surveyed throughout the City of New York during the summers of 2006 and 2007. Overall, 74.3% of the sample trees were alive when surveyed and the remainder were either standing dead or missing. Results of our initial analyses reveal that highest mortality rates occur within the first few years after planting, and that land use has a significant effect on street tree mortality. Trees planted in one- and two-family residential areas had the highest survival rates (82.7%), while young street trees planted in industrial areas, open space and vacant land had the lowest rates of street tree survival (60.3% -62.9%). Also significant in predicting street tree success and failure are species type, tree pit enhancements, direct tree care/stewardship, and local traffic conditions. These results are intended to inform urban forest managers in making decisions about the best conditions for planting new street trees

Quantifying the Offset of Greenhouse Gas Emissions at the University of North Alabama

This study quantified the discrete and areal carbon sequestration capacity of the University of North Alabama’s green infrastructure. USDA i-Tree was used to analyze and report on the carbon sequestration of 1487 campus trees, which provided -82.29 metric tons CO2 sequestration. Quantification of CO2 sequestered for 61 acres of undisturbed stands of native forest is -56.45 MT CO2. A summated sequestration capacity of UNA green infrastructure is estimated at -138.74 metric tons of CO2 per year. Sequestration capacity of the University of North Alabama’s green infrastructure is compared to their direct emissions for 2017. The scope I CO2e emissions from gasoline, diesel, and natural gas totaled 1,982.10 Metric tons. The offset capacity of UNA green infrastructure was estimated at 6.98% of UNA Scope I emissions, leaving a balance of 1,848.36 Metric tons of CO2e emission as UNA’s Scope I footprint