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Educational Sessions

Heritage Trees Symposium

Assets and Liabilities of Large Old Trees in Urban Landscapes
Tuesday, 11 August 2015
8:30 AM — 11:00 AM
Osceola Ballroom D
A, M, Bm

Urban trees generally live a shorter life than their forest counterparts. Yet in many cities, a small number of trees reach great size and age.  These trees may be pre-settlement trees left in place during a city’s growth, or trees planted early in the life of a city.  Although not common, large old trees are significant assets and sometimes significant liabilities to cities. The symposium will begin with two case studies of ancient tree management in urban landscapes and then address risks and benefits and risk management of large urban trees. The symposium will conclude with a panel discussion on emerging guidelines for management of large trees in urban environments.

  • Opening Remarks and Moderater - Bryant Scharenboch, PhD, Morton Arboretum

  • Longevity and Management in Ancient Urban Trees of the Bluegrass When the Bluegrass region of Kentucky was settled in the 1770s, there were extensive woodland pastures consisting of very large, open-grown trees shading grass and cane. This habitat was created by bison and drought. Farmers had little reason to cut down the trees, and today there are still thousands of acres of ancient woodland pastures. As urban areas grew, many of these trees were lost. Fayette County, Kentucky, lost 90% of its bur oaks in the last 60 years. Many trees remain in urban areas. This trees are slowly disappearing due to development, poor management and lightning strikes. The Old Schoolhouse Oak is a case study in careful management of an ancient bur oak in a new housing development. A clear understanding of physiologic condition and root distribution, removal of competing vegetation, avoidance of damage by construction equipment and lightning protection are contributing to the preservation of this iconic tree. -Tom Kimmerer, Venerable Trees

  • Preservation of Large Trees at the University of Pennsylvania - While all trees within our urban landscapes are valuable, large trees play a particularly vital role as the most important green infrastructure element.  Large trees provide the greatest environmental, economic, and social benefits, and fundamentally contribute to the health and welfare of almost 80 per cent of the US population and over half the world population living in urban areas. However, as a tree grows and tree-related benefits increase, tree-related risk concurrently increases, since large, mature specimens are more likely to shed increasingly larger branches or develop conditions predisposing the whole tree to failure.  This presentation will discuss how tree-related risks and benefits are assessed and evaluated, and how tree owners and managers strive to balance their risk tolerance with the many benefits trees contribute to our urban communities.- Jason Lubar, Morris Arboretum
  • Elderly Trees are Quite Different From Young Trees Their appearance, physiology, needs, cultural tolerances, and other aspects require unique attention. As arborists it is essential that we understand these differences and change the way we interact with elderly trees. This session will discuss, in very simple basic terms, how to identify elderly trees, discuss the contrasts from younger trees, and discuss how as arborists our treatments of elderly trees need to adapt.-Norm Easey,  Florida Chapter ISA

  • Managing Mature Trees Under Limited Water/Drought Conditions  The City of Austin, Texas has an estimated 200,000 trees in managed park lands.  Of this population, roughly half are considered to be established trees, and about 7% are mature trees.  In 2011, Texas experienced one of the worst drought years in history, resulting in a loss of an estimated 5.6 million urban trees.  Drought has persisted in the state, leaving the lake system which supplies water to the City of Austin at extremely low levels.   The City has had watering restrictions in place for several years now, and without significant rainfall, is expected to further restrict water usage.  This has made protecting the mature trees in our parks even more challenging.  This presentation will outline the steps that we are taking to manage our mature trees through this time of drought and water restrictions, and how we are attempting to engage the community to help.– Lara Schuman, City of Austin, TX

  • Panel Discussion - Developing guidelines for management of large, old trees

Presenter Information

    • Bryant C Scharenbroch
      Bryant Scharenbroch is an Assistant Professor of Soil Science at University of Wisconsin – Stevens Point and a Research Fellow at The Morton Arboretum. Bryant is an Associate Editor for Arboriculture and Urban Forestry. He is the chair of the Urban Tree Growth & Longevity Working Group under AREA and ISA and the chair of the Urban and Anthropogenic Soils Division of Soil Science Society of America. In 2013, Bryant received the ISA’s Early Career Scientist Award. Bryant has a Ph.D. in Soil Science from University of Wisconsin – Madison, an M.S. in Plant Science from University of Idaho, and B.S. degrees in Urban Forestry and Forest Management from University of Wisconsin – Stevens Point. 
    • Tom Kimmerer
      Tom Kimmerer, PhD, is Chief Scientist at Venerable Trees, Inc, a nonprofit corporation devoted to the conservation of ancient trees in the Bluegrass. He has a BS in Forest Biology from SUNY ESF and a PhD in forestry and botany from the University of Wisconsin-Madison. Tom has taught tree physiology, forest biology and urban forestry in the US, Indonesia and Malaysia. He was a faculty member at the University of Kentucky and Universiti Putra Malaysia, where he was a senior Fulbright Scholar. He is the author of Venerable Trees: History, Biology and Conservation in the Bluegrass (Available Fall 2015) and the forthcoming book The Age of Trees.
      Venerable Trees, Inc, Lexington, KY, USA
    • Norm Easey

      Norm Easey has been an active member of ISA for over 35 years and was the first Student Member of ISA in 1978.  Norm has been active in urban forest management and arboriculture in Florida since receiving his bachelors' degree in Forestry/Resource Management in 1980 from the University of Wisconsin. He is currently the Chief Executive Officer of the Florida Chapter ISA. Mr. Easey for 18 years was the Forestry Manager for Sarasota County, Florida. Mr. Easey also has a part-time urban forestry consulting practice, wherein he specializes in tree risk assessment and urban forest management. Mr. Easey currently serves the International ISA in many capacities including: Chair of the Certification Liaison Committee, Certification Board, and Nominations and Elections Committee. Mr. Easey has also been a County Forester with the Florida Forest Service. Mr. Easey is a past Chairman of the Florida Urban Forestry Council and Board Director of the International Society of Arboriculture. He is also a long-standing member of Society of American Foresters.


    • Jason Lubar

      Jason is the Associate Director of Urban Forestry at Morris Arboretum of the University of Pennsylvania in Philadelphia. He is an ISA PennDel Chapter Board Member and CoR Representative, serves on Penn-Del’s Nursery Quality Task Force, and is a Board Certified Master Arborist and a member of the American Society of Consulting Arborists. He also is on the Executive Board and is treasurer of the Pennsylvania’s Urban and Community Forestry Council.

    • Lara Schuman
      Lara Schuman is the Urban Forestry Program Manager for the City of Austin, Texas Parks and Recreation Department.  She is a native Austinite, and a graduate of the University of Texas.  She lived for many years in Wyoming, where she ran a tree care company with her husband.  Lara is an ISA Certified Arborist, and the current Vice President of the Texas Chapter of the International Society of Arboriculture.

      City of Austin, Texas