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Phone: +1.678.367.0981
Fax: +1.240.547.1795

Mailing Address

International Society of Arboriculture
PO Box 191
Annapolis Junction, MD 20701
United States

Physical Address

International Society of Arboriculture
270 Peachtree St NW, Suite 1900
Atlanta, GA 30303
United States

Order Delays Due to Physical Inventory

Due to ISA's annual physical inventory, orders placed between
2 p.m. EDT, Thursday, 20 June 2019, and 11:59 p.m. EDT, Friday 28 June 2019, will not ship until the week of 1 July 2019

Please plan your ordering accordingly.

We will resume regular turnaround times
1 July 2019.

Thank your for your patience.

Questions? Please call the customer service team at (678) 367-0981.

    Climbers' CornerTree Academy

    Effects of Root Severance on Tree Health and Stability


    The aims of this study were: 1) to evaluate the effect of two levels of root severance on tree growth and physiology of two shade tree species supposed to differ in tolerance to root manipulation; 2) to evaluate the effects of root damage on tree stability by theoretical calculations and pull test.

    The root system of 48 established Aesculus hippocastanum (25-30 cm circumference) and 48 Tilia x europaea (25-30 cm circumference) growing in a loamy soil was damaged according to the following treatments:  1) roots were severed only on one side of the tree by excavating a trench (70 cm deep and 50 cm wide) 40 cm apart from the root flare (Moderate Damage); 2) roots were severed at two opposed sides of the tree by excavating two trenches (both 70 cm deep and 50 cm wide) 40 cm apart from the root flare (Severe Damage); 3) roots were not damaged (control). Shoot and stem diameter growth, leaf gas exchange, chlorophyll fluorescence and water relations were assessed for the 4 years following the damage. Roots were dug with Airspade a few months and 4 years after the damage to assess the size of the root plate and to calculate the uprooting resistance index according to standard methodology. The pull test was performed immediately after the severance and after 4 year using Orebla analysis software.

    Effects of root severance on tree stability (both directly measured using pull test and calculated from the size of the root plate and of the crown) and recover from root damage of the two species in the 4 years after severance will be discussed in the presentation. Also, the impact of root loss on growth, leaf gas exchange and water relation will be described and the potential for recovery of the two species will be evaluated. 


    Alessio Fini is a researcher at the Department of Agri-Food Production and Environmental Sciences at FlorenceUniversity. Since 2005, he has been working on projects regarding sustainable cultivation techniques for nursery production and urban forestry and on stress tolerance of urban trees. Research topics include: reduction in use of herbicides, irrigation and chemical fertilizers; effects of shading on leaf gas exchange and leaf anatomy; alternative techniques to tillage and their effects on plant physiology; effects of mulching on plant physiology and soil chemical, physical and biological properties; development of native and species-specific mycorrhiza to improve health and growth of urban trees; development of nursery pre-conditioning techniques to improve success at transplant; roles of phenolic compounds in plant response to stress and plant responses to climate change. In 2011, he got a PhD in “Animal and vegetal production for sustainable landscape development” at the University of Florence. His PhD thesis dealt with the mechanisms of drought tolerance of shade trees and the selection of drought tolerant species. He is author of about 85 publications in international peer-reviewed journals, book chapters and conference proceedings. 

    Climbers' CornerTree Academy

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