72 Sanders et al.: Size Expectations for Urban Trees with Regard to Designed Space trees have not yet reached a proven or repeatable maximum size in trunk diameter. As the area of unpaved surface increased in the planting zone, from pavement opening, to linear planting strip to park/lawn situations, the terminal size trunk diameter of the trees increased. While it is understood that performance expectations need to be on a species level, the data can provide guidance on the consequences of varied design choices and expectations on plant performance to scale design intentions with definitive outcomes. This could provide a context for developing urban site index or urban size expectation to help determine harvest interval, the time when trees begin to accrue costs at a greater rate than return- ing ecosystem services. This study also used 11 cities whereas a manager would typically use this method in one city. Although there are differences in soils, compaction, and other site specific criteria, the relationships described in all 11 communities are con- sistent and provide for a start of an urban tree size expectation. Although researchers identified a gradient in the tree size by planting site location, it is not suggested that this is the definitive maximum for these species. Care is needed in the interpretation of these results, but the methods provide a robust and repeatable benchmarking approach for long-term evaluation by managers and researchers. It should also be noted that small trees were observed in small sites; but not in large sites, this is common for the urban forest. Common wisdom dictates that large trees will provide more shade, which is why small trees tend not to be planted in such sites. CONCLUSION In urban forest management, a goal would be to minimize pre- mature tree losses and manage trees to the point at which trees begin to accrue costs at a greater rate than providing ecosystem services. The goal was to establish a method to develop a con- struct for cohort senescence, which could be easily developed and replicated from existing data in regional inventories. Thus, the method described could be used with existing community tree inventories. This study seeks to improve management by de- veloping consistent site types to use in conjunction with current inventory practices. With this data, maximum size and a reason- able life span has been determined for several tree species and a conceptual framework has been developed. DBH is a viable surrogate for age. Additionally, design plans need to accommo- date a reasonable design size expectation to then provide a rea- sonable idea of services for the associated investment if some service is associated with canopy size/volume. Within such planning and evaluation, this rapid assessment is very useful. LITERATURE CITED Bassuk N., D. Curtis, B.Z. Marranca, B. Neal. 2009. Recommended Ur- ban Trees: Site Assessment and Tree Selection for Stress Tolerance. Urban Horticulture Institute Department of Horticulture Cornell Uni- versity, Ithaca, New York, U.S. 128 pp. Berrang, P., D.F. Karnosky, and B.J. Stanton. 1985. Environmental fac- tors affecting tree health in New York City. Journal of Arboriculture 11:185–189. Bond, J. 2010. Tree condition: Health. Arborist News 19:34–38. Bond, J. 2012. Urban Tree Health: A Practical and Precise Estimation Method. Urban Forest Analytics LLC, Geneva, New York, U.S. 130 pp. Cannell, J.J. 1988. Nationally normed elementary achievement testing in America’s public school: How all 50 states are above the national average. Educational Measurement Issues and Practice 7:5–9. ©2013 International Society of Arboriculture Chacalo, A., A. Aldama, and J. Grabinsky. 1994. Street tree inventory in Mexico City. Journal of Arboriculture 20:222–226. Clark J., N. Matheny, G. Cross, and V. Wake. 1997. A Model of Urban Forest Sustainability. Journal of Arboriculture 23(1):17–30 Day, S.D., and R. Amateis. 2011. Predicting canopy and trunk cross- sectional area of silver linden (Tilia tomentosa) in confined planting cutouts. Urban Forestry & Urban Greening 10:317–322. Fraenkel, J.R., and N. Wallen. 1992. How to Design and Evaluate Research in Education. McGraw-Hill, New York, U.S. 620 pp. Gerhold, H., N. Lacasse, and W. Wandell. 1993. Street Tree Factsheets. Penn State College of Agriculture Sciences, University Park, Penn- sylvania, U.S. Grabosky, J., and E. Gilman. 2004. Measurement and prediction of tree growth reduction from tree planting space design in established park- ing lots. Journal of Arboriculture 30:154–164. Hightshoe, G. 1988. Native Trees, Shrubs, and Vines for Urban and Rural America. A Planting Design Manual for Environmental Designers. John Wiley and Sons, New York, U.S. 819 pp. Hitchmough, J.D. 1994. The management of trees in the urban landscape. pp. 267–300. In: J.D. Hitchmough (Ed.). Urban Landscape Manage- ment. Inkata Press, Sydney, Australia. Jim, C.Y. 1994. Evaluation and preservation of champion trees in urban Hong Kong. Arboricultural Journal 18:25–51. NJ DEP Community Forestry. 2011. New Jersey shade tree and commu- nity forestry assistance act. Accessed 1/17/2012. Pescott, R.T.M. 1968. Life expectancy and planned replacement. pp. 53–59. In: A.W. Wilkie (Ed.). Proceedings of the symposium on street trees. Australian Institute of Parks and Recreation, Melbourne, Australia. Sanders J., and J. Grabosky. 2013 (in press). Factors influencing early mortality and survival of New York City street trees in the Urban Forest. Urban Ecosystems. Schoonjans, F., D. DeBacquer, P. Schmid. 2011. Estimation of population percentiles. Epidemiology 22:750–751. Sinclair, W.A., and G.W. Hudler. 1988. Tree declines: four concept causality. Journal of Arboriculture 14:29–35. Solotaroff, W. 1911. Shade Trees in Towns and Cities. John Wiley & Sons, New York, New York, U.S. 287 pp. Jessica Sanders (corresponding author) Casey Trees 3030 12th St NE Washington D.C., 20017, U.S. Jason Grabosky Rutgers - Ecology Evolution Nat Resources 14 College Farm Road New Brunswick, New Jersey 08901, U.S. Paul Cowie Paul Cowie & Associates 11 N. Beverwyck Road Lake Hiawatha, New Jersey 07034, U.S.
March 2013
| Title Name |
Pages |
Delete |
Url |
| Empty |
Search Text Block
Page #page_num
#doc_title
Hi $receivername|$receiveremail,
$sendername|$senderemail wrote these comments for you:
$message
$sendername|$senderemail would like for you to view the following digital edition.
Please click on the page below to be directed to the digital edition:
$thumbnail$pagenum
$link$pagenum
Your form submission was a success. You will be contacted by Washington Gas with follow-up information regarding your request.
This process might take longer please wait
