Bob Polomski, Ph.D.Clemson Extension Horticulturist

Clemson University, South Carolina

September 12, 2010

Emerging Issues in Arboriculture

http://hort.ufl.edu/woody/planting

Emerging Issues in Arboriculture

Tree selection Production Planting Establishment Urban soil management (“soil

restoration”

Plant Health Care

Tree Selection The search for the perfect

landscape/street tree continues….        --evaluation of new species and cultivars

Tree SelectionBiomechanics: study of

the structural behavior of trees

Study branch failures Learn why some trees

stay upright in a storm while others fail;

Prune to prevent storm damage

Tree Production Effects on successful

tree establishment and longevity    --evaluate container

types and container treatments to

reduce/ eliminate circling roots

Planting and establishmentAn estimated 80 percent of all landscape

tree problems originating below ground relate to quality and placement of the root system.  Structural root defects and root planting depth issues can occur during all stages of tree production and establishment including nursery propagation and production, landscape specification development and planting, and post‐planting and transplanting maintenance.  

Tree Selection

Tree Planting• Bare root

--Develop methods and products to use for bare-rooting trees at planting time (root washing, pressure washing, and air excavation)

Bassuk, N. L. 1998. Creating the urban forest: the bare root method. 1998. Urban Horticulture Institute Cornell University Ithaca, NY.

Tree Planting Bare rooting--technique to reveal tree

roots prior to finishing the planting or transplanting process

Need to see root defects--if possible, correct and adjust planting height 

“Bare Root to Bare Root – Coming Full Circle” (www.mortonarb.org/deeptreeroots/pdf/LBG_Abstracts.pdf)

Tree Planting Bare rooting--technique to reveal tree

roots prior to finishing the planting or transplanting process

Need to see root defects--if possible, correct and adjust planting height/depth. 

“Bare Root to Bare Root – Coming Full Circle” (www.mortonarb.org/deeptreeroots/pdf/LBG_Abstracts.pdf)

Tree Planting Plant trees at the

proper depth--Deep roots of landscape trees: A comprehensive guide to current research and practice

(www.mortonarb.org/deeptrees)

Planting too deep is deadly

93% of professionally-planted trees (Smiley and Booth, 2000)

75% of nursery-grown trees (Maynard 1995)

Tree Planting Container-grown

--evaluate root pruning strategies: slicing, shaving, bare rooting, or butterflyingAlleviate root defects after planting and ensure survival and vigorous growth of trees after planting.

Planting and establishment Container-grown

--evaluate root pruning strategies: slicing, shaving, bare rooting, or butterflying

Post-planting survival and

establishment• New technologies to

improve post-plant survival and stress resistance in urban trees,e.g., biostimulants, humectants, mycorrhizae, etc.

Established Trees Urban soil management (“soil

restoration”)--Root Invigoration®

Established Trees Urban soil management (“soil

restoration”)--Root Invigoration®

Established Trees

Planting and Establishment Urban soil management (“soil

restoration”)--Root Invigoration®--Aerated Compost Tea (ACT)

www.masslaboratory.org/mass_015.htm

Planting and establishment Urban soil management (“soil

restoration”)--Root Invigoration®--Aerated Compost Tea (ACT)--Biochar – carbon-rich product (wood, manure, leaves) heated in absence of O2

Planting and establishment

http://abcnews.go.com/GMA/JustOneThing/video/green-plant-soil-biochar-11486209

Plant Health Care: Pests Emerald ash borer (Agrilus planipennis)

--Native of China and Eastern Asia--Michigan in 2002-13 states and parts of Canada

www.agri.ohio.gov/divs/plant/eab/eab-index.aspx

PHC: Pests EAB management

www.emeraldashborer.info/files/Multistate_EAB_Insecticide_Fact_Sheet.pdf

PHC: Pests Walnut twig beetle and

thousand cankers disease of black walnut (Juglans nigra)—insect-disease complex

Geosmithia sp.Fusarium solani

PHC: Pests Walnut twig beetle and

thousand cankers disease of black walnut (Juglans nigra)—insect-disease complex(Geosmithia sp. and Fusarium solani) 1990s Utah 2001 New Mexico

PHC: Pests Walnut twig beetle and

thousand cankers disease--Black walnut decline

PHC: Pests Asian long-horned

beetle (Anoplophora glabripennis)

--native to Japan, Korea, and China--1996 discovered in Brooklyn and Amityville, NY--Maples and horsechestnuts, also ash, poplar, willow, elm, mulberry, and black locust

PHC: Pests Asian long-horned beetle

PHC: Pests Asian long-horned beetle

Plant Health Care Novel disease control compounds to

reduce pesticide usage in the arboricultural industry:--“Biopesticides” - synthetic or natural compounds such as plants, microorganisms, and certain mineralscontrol pest and foliar diseases.

Arboricultural Research Research

More research

Even more research

Application

“With great power…

Comes great responsibility.”

Only you can speak for trees.

Angel Oak, Charleston, SC