Street Tree Management Research Articles

Statewide assessment of street trees in New York State, USA

In the United States, street tree management and planning occurs at regional, state, and local levels. However, state and federal officials charged with managing streets trees at the regional and state levels typically lack the comprehensive, detailed information available to local officials in a street tree inventory such as species composition and tree size distribution. Statewide street tree assessments employing a variety of methodologies have been conducted to fill this knowledge gap. This paper examines these past assessments and builds upon them in conducting a street tree assessment for New York State in which geographic variability in statewide street tree inventory data is accounted for through weighted averaging of estimates.

Comparing street tree assemblages and associated stormwater benefits among communities in metropolitan Cincinnati, Ohio, USA

Green infrastructure approaches leverage vegetation and soil to improve environmental quality. Municipal street trees are crucial components of urban green infrastructure because they provide stormwater interception benefits and other ecosystem services. Thus, it is important to understand the patterns and drivers of structural heterogeneity in urban street tree assemblages. In this study, we compared the forest structure of street trees across nine communities along both geographic and demographic gradients in metropolitan Cincinnati, Ohio, USA. Specifically, we used a two-part statistical model to compare both the proportion of sampled street segments containing zero trees, and basal area magnitude for street segments with trees. We made community-scale comparisons based on street tree management, socioeconomics, and geographic setting. Then, using modeled stormwater interception estimates from i-Tree Streets, we investigated the implications of heterogeneity in street tree assemblages for stormwater interception benefits. The forest structure of street trees varied across communities in relation to management practices, namely participation in the Tree City USA program. As a consequence of this structural difference, we observed a stark discrepancy in estimated stormwater interception between Tree City USA participants (128.7m3/km street length) and non-participants (59.2m3/km street length). While street tree assemblages did not vary by community poverty status, we did find differences according to community racial composition. In contrast to previous research, basal area was greater in predominantly black (i.e., African American) and racially mixed communities than in predominantly white communities. We did not observe structural differences across geographic strata. This research underscores the importance of proactive management practices for increasing the forest structure of street trees. Our findings regarding socioeconomics and geographic setting contrast previous studies, suggesting the need for continued research into the drivers of structural heterogeneity in street tree assemblages.

Building Partnerships: Connecting Communities, Master Gardener Volunteers, Industry, and Extension Through Tree Surveys

Extension, Master Gardener volunteers, and industry professionals can partner in order to provide a significant benefit to a community. The result of this partnership and subsequent tree inventory provides communities with an essential street tree management tool at a substantial cost savings. In addition, there is a greater awareness among the partners regarding their assets and abilities that can lead to a positive impact on a community.

춘천시 도시림의 관리실태 및 시민의식 분석

The research on urban forests in Chuncheon, so far, has mainly conducted in Ponguisan urban forest. Research on other urban forests in Chuncheon was scarce. Accordingly, in this study, the author chose the main urban forests in Chuncheon and tried to find a way of efficient establishment and management of urban forests in Chuncheon by field and questionnaire survey. The research findings, there were several reasons why effective management can not be implemented in the main urban forests in Chuncheon. To solve these problems and make an efficient establishment and management of urban forests in Chuncheon, the first way is to make forest management plans on the urban forest in Chuncheon and expand administrative organization, personnel and budget. Establishment and management of urban forests needs a practical, strengthened overall management system. The second way is to enhance the regional and functional characteristics for urban forest, expand the area of urban forests, and enhance management of Street trees. The third way is to designate Urban Nature Park or Urban Park for the main urban forests in Chuncheon and need to change the ownership of the urban forests by purchasing. The fourth way is to respond to Chuncheon citizen's preference and their way of utilization when create the urban forests in Chuncheon, expand convenience facilities, relaxation facilities as well.

THOUGHTS ON THE POLITICS AND ECONOMICS OF URBAN STREET TREES

Summary Street trees, and especially urban street trees, provide major services to people and places. They generate local character and distinctiveness and add value to properties, and increase the desire to live or work in a particular locale. Not only that but they improve quality of life and they benefit human health. We even know now that these trees help climate-proof our urban centres by lowering summer temperatures up to several degrees, by attenuating storm-generated runoff and minimising flood risk, and by removing particulates and other pollutants from the city atmosphere. But such urban street trees are at risk and with likely cuts in UK local government services, the threats will soon increase dramatically. These trees, especially in an urban environment are stressed and require care and attention and their champions are often local government tree officers. This provision of service costs money and necessitates well-qualified professional support. However, observations in a number of conurbations over thirty years or more, and discussions with senior tree officers, suggests that local government and other responsible bodies often prefer to remove trees which they deem to be problematic. Generally this means those now mature forest trees that were planted by Victorian and Edwardian developers. This action is in order to minimise maintenance costs, to avoid damage to pavements, and to resolve other potential problems that officers, elected members, or the public associate with the older and bigger trees. Of course in urban areas there is the additional problem that these big trees were not planted in optimum conditions and the ambient environmental stresses sometimes but by no means always lead to premature decline. There are many examples of excellent practice in urban street tree management but one worries about the future in a DIY ‘Bigger Society’ scenario. Professional practice must be maintained even in the face of intransigent economic issues affecting both public and private sectors. The marked decline in arboricultural practitioners taking up options of professional training is a clear indication of the depth of the economic impacts of the downturn. However, it is argued that these trees bring huge benefits to a community and to a conurbation and that this includes enhanced economic prosperity. The problem with this is that the costs are borne by local government which is increasingly cash-strapped, but the benefits which accrue are to local business and to the community at large. The cost and the benefits are not placed with the same organization and so to transfer the financial incentive to maintain the resource there needs to be a movement of tax revenues to the service provider. This is not what central government will wish to hear.

Artificial Neural Network Prediction of Street Tree Growth Patterns

Municipal administrations annually allocate a large budget to preserve their urban trees. However, survival and growth rates of street trees vary drastically as they are strongly influenced by adverse environmental conditions. Consequently, arboricultural programs must be locally adapted to provide care to stressed trees. Artificial neural networks were used to identify poorly growing trees by learning from growth patterns detected by multivariate statistical analyses. Seven species that are representative of 75% of the Montreal street tree population were sampled: Acer platanoides L., Acer saccharinum L., Celtis occidentalis L., Fraxinus pennsylvanica Marsh., Gleditsia triancanthos L., Tilia cordata Mill., and Ulmus pumila L. Individuals were of different age, dissimilar morphological characteristics, and had variable distribution among urban ecological zones. Radial basis function networks (RBFs) were selected as the model type. To assess RBFs robustness and predictive capability on unknown data, global and specific cluster classification was used. When global classification was estimated, the lowest accurate prediction value was 83% and the highest 93%. The average value for all species taken together was 89%. Similarly, the classification success within groups per species was adequate. For most species, test files prediction accuracy ranged from 80% to almost 100%. This indicates that RBFs are well suited for classification decisions. These results have an impact on the management of street trees. Given the present findings, integrating robust predictive algorithms into data banks as a decision-support system is a conceivable avenue. Artificial-intelligence-based models might probably become important elements of efficient street tree management plans.

지방도시 가로 녹지의 존재효과에 대한 보행자와 상업종사자의 의식 연구 - 충주시 가로수를 대상으로 -

The overall purpose of this study was to investigate pedestrians and commercial business men and employers' recognition on management of street trees and green spaces along street sides. The followings were main results of this study. Both pedestrians and commercial business men and employers mostly perceived positive influence of street trees on urban environment and their business. In addition, pedestrians gave higher scores of positive influence of trees function than those of commercial business men and employers. Pedestrians showed strong intention to participate management activities of street trees or green spaces. This study indicated that negative perception on street trees came from improper management rather than existence of street trees. Therefore, more intensive management actions are needed.

東京２３区における街路樹ハナミズキの植栽環境と生育状況

The planting environment and the growing condition of street trees were surveyed to contribute to appropriate street tree establishment and management. The distribution and site condition in terms of road types and width and land use for dogwood street trees in the 23 wards of Tokyo prefecture were analyzed using GIS. Attributes of roads, sidewalks, planting layouts and background, and tree vigor were surveyed at the 49 selected sites. Dogwood street trees were mainly planted in residential, commercial and business areas. It was found however that they had different backgrounds and that in different growing conditions depended on the site condition. Especially, the number of sites where dogwood trees are planted drastically increased recently on national road and Tokyo metropolitan government roads mainly on the occasion of construction works on the roads. On ward roads, they were planted as improvement of sidewalks especially in commercial and mixed land use areas. Tree vigor showed differences for different site conditions. It was considered that the selection and management of street trees should be based on site condition.

190 Growth Response of Four Tree Species to Fertilization and Humate Additives to CU Soil

CU soil is a material primarily composed of clay loam soil and crushed stone designed for use under pavement to promote street tree root growth in a durable pavement section, such as sidewalks or parking lots. One concern is the low total soil fraction from which tree roots can meet nutritive demands. At issue is the long-term nutrient management of street trees once the root zone has been rendered inaccessible due to the pavement wearing surface, although in 3-year field tests, there were no differences found between a CU soil material and an agricultural field control. CU soil treatments were produced in a factorial design with a patent applied for processed humate additive, and a nursery production fertilization treatment. Bare-root seedlings of Salix nigra Marsh, Platanus × acerifolia Willd., Ginkgo biloba L., and cell plugs of Ficus benjamina L. were grown in treatment containers for 5 months. A Minolta SPAD-502 was used to evaluate relative chlorophyll content as an indication of leaf tissue nutrient levels. Plant growth as a function of new growth dry weight was calculated. Soil samples were collected at the end of the study and were analyzed to evaluate the impact of humate admixes in nutrient availability. The fertilization treatments positively influenced leaf color and growth for all species. The CU soil control plants displayed significantly lower chlorophyll levels, but overall growth differences were less dramatic—insignificant in some cases. The humate additive did not consistently affect leaf color. The humate additive alone did not affect plant growth, but a significant positive interaction with the fertilizer treatment was evident for Platanus and Ficus. The positive interaction was insignificant in Salix and non-existent in Ginkgo.

192 Growth Response of Salix nigra Marsh. to Fertilization, Humate Additive, and Mycorrhizae Inoculation in a CU Soil Container Study

CU soil is a material primarily composed of clay loam soil and crushed stone designed for use under pavement to promote street tree root growth in a durable pavement section, such as sidewalks or parking lots. One concern is the low total soil fraction from which tree roots can meet nutritive demands. At issue is the long-term nutrient management of street trees once the root zone has been rendered inaccessible due to the pavement wearing surface, although in 3-year field tests, there were no differences found between a CU soil material and an agricultural field control. CU soil treatments were produced in a fractional factorial design with a patent applied for, processed humate additive, a nursery production fertilization treatment, and a mycorrhizae inoculation package of Pt and various VAM species. The mycorrhizae/fertilizer treatment was eliminated for plant availability restrictions. Bare-root seedlings of Salix nigra Marsh. were grown in treatment containers for 5 months. A Minolta SPAD-502 was used to evaluate relative chlorophyll content as an indication of leaf tissue nutrient levels. Plant growth as a function of root dry weight, shoot dry weight, and shoot: root ratio was analyzed. Soil analyses were conducted on media samples collected at the end of the study to evaluate the impact of humate admixes in nutrient availability. The fertilization treatments positively influenced leaf color, shoot weight, root weight, and shoot: root ratio. There was no impact from the mycorrhizae inoculation on leaf color or growth. There was no impact from the humate additive on leaf color or growth. There were no additive effects found in the treatment levels.

A Street Tree Inventory for Massachusetts Using a Geographic Information System

The creation of a street tree inventory using Geographic Information System (GIS) software can greatly enhance municipal tree management. Many different techniques were explored in an effort to map tree locations efficiently and accurately, including aerial photo interpretation, Global Positioning Systems (GPS), surveying techniques, and tree placement on existing base maps. Additionally, several different types of basemaps were tested to optimize accurate cartographic transfer of tree locations. Detailed data about tree attributes were collected in the field using a portable, preprogrammed computersothatthese data would be compatible with a GIS. The spatial tree location data were joined with the tree attribute data to produce afully functional spatial database for street tree management purposes. Based upon two case studies, the advantages and disadvantages of each project phase are discussed and qualified.

WHITE COLLAR COMPULSORY COMPETITIVE TENDERING (CCT): THE DEATH KNELL FOR ARBORICULTURAL OFFICERS AND THE END OF PROFESSIONAL STREET TREE MANAGEMENT

Summary The implications of the implementation of Compulsory Competitive Tendering (CCT) are discussed in relation to posing a direct and indirect threat to arboricultural officers in metropolitan authorities. The mechanisms of this threat are laid out firstly, within the terms of client street tree management contracts, and secondly, how this may impact on the level professional tree care.

Designing Alternatives to Avoid Street Tree Conflicts

The use of representative crossectional illustrations of various street types presents a useful and effective method of examining the relationship between overhead electric lines and street trees. This design system can serve as the basis for proper species and site selection. Through the development of a series of street type criteria, ranging from larger major arterial roads to smaller local streets, this paper presents a workable and useful methodology that is available to municipalities and utility companies for aiding in the selection and management of street trees.

The Factor Structure of Street Tree Attributes

A factor analysis of 816 householder evaluations of street trees showed a general benefits factor and discrete annoyance factors in such areas as ground disturbance, disease, reduced visibility, and debris from fallen tree parts. Benefits were more highly related than annoyances to overall satisfaction with the street tree. The findings have implications for management of street trees and for future surveys of attitudes.

The Management of Urban Street Trees Using Computerized Inventory Systems

The microcomputer has made possible the storage, access and analysis of large quantities of data at high speed and low cost, it is the objective of this paper to describe the contribution the microcomputer can make towards the management of street trees in urban areas. Benefits and problems associated with urban trees are outlined and the work of the Arborist and workforce is described. Existing systems of recording, filing, and retrieving information, are compared with those incorporating the use of a computer. The paper focuses on the application of recent developments in computer technology towards data management for the Arborist. Some of the difficulties associated with the transition from a manual filing system to one that is computer based, are discussed. Further areas of research and development in this field are explored.

The Pruning of Trees in Towns

THE services of Prof. Bayley Balfour, F.R.S., have been obtained by H.M. Office of Works to inquire into the justness or otherwise of complaints made in regard to the treatment of the young trees in the Mall. His report, which has just been issued from the Stationery Office (Cd. 5823, price 21/2d.), must be gratifying to those who have charge of the trees, for he finds nothing to justify adverse criticism of the pruning. On the contrary, he was impressed by the evidence of sound practical knowledge and scientific principle shown in their treatment. It was high time that someone in a position of authority should have been called on to lay down the principles that govern, or should govern, the pruning of trees in public thoroughfares. The outcry periodically made in the daily Press is usually marked by want of knowledge and unfairness. As a matter of fact, there is no work more thankless in nature than the management of street trees. In London and other great urban areas the planter's choice is restricted to a few species (of which the plane is the chief and best) which experience has proved will thrive, but which, as regards size, are quite unsuited to the spaces usually available for them. In the Mall this difficulty does not arise, for the space is ample. The object there is to control the growth of the trees that have been planted so that the foundations of a stately avenue may be laid.