Tree Health & Rain Bird RWS Series Webinar 30 June 2010 Specifiers Topics Roles of Trees Tree Survival Tree Maintenance Root Watering Series Root Watering Cases Specifier Benefits Sources Roles of Trees 1
Roles of Trees Environmental Benefits Reduce surface water run-off Reduce soil erosion Absorb air pollutants Sequester carbon Reduce noise pollution Cools as evapotranspirator Provide habitat for urban wildlife Roles of Trees Economical Benefits Increases property values from 3 to 20 percent Serve as wind barriers thereby decreasing heat bills in the winter months Studies have shown that trees decrease energy consumption in winter months by 25% Shade from tree canopies decrease electrical bills in the summer Tree Survival 2
Tree Survival Newly Planted Trees 19% of newly planted trees die within the first 2 years 56% of newly planted tree mortality is due to water and nutrient stress In a typical transplant project, as many as 20% of trees do not survive Tree Survival Causes Most frequent causes of newly planted urban tree mortality Water and nutrient stress (56%) Vandalism (18%) Guard girdling (12%) Soil compaction (9%) Improper staking and tying techniques (mechanical injury) (5%) Tree Survival Causes (cont) Poor soil conditions are due to Alkalinity Toxics and pollutants High temperature Lack of physical space in soil pit 3
Tree Survival Causes (cont) Poor soil conditions are due to (cont) Compaction of soil which leads to reduces total air-filled pore space & average pore size increases mechanical resistance to root penetration reduces oxygen and water holding capacities nutrient and water stress reduced root elongation growth reduced radial growth shallow rooting stunted whole tree form fewer symbionts / codependents (favors low oxygen-requiring organisms) (not enough mycorrhizae fungi) Tree Survival Causes (cont) Poor atmospheric conditions are due to High temperature Toxics and pollutants High potential evapo-transpiration (ET) Large-scale natural disturbances such as Hurricanes Ice storms Invasive pests Tree Survival Transplant Shock Roots travel 2.5x the tree height away from the trunk Depending on transplanting methods, trees loose a portion of their their root system 85% of root growth occurs within 18 (46 cm) of the soil surface Trenching / vertical cuts range to over 20 (51 cm), cutting roots in their path Problem appears out of sight but magnifies itself within months 4
Tree Survival Transplant Shock (cont) Tree recovery takes time Reduced root system is unable to supply the quantity of nutrients and water the upper portion of the tree needs for normal growth 4 caliper tree will require 5 years to regain size of original 18 diameter root system 10 caliper tree will require 13 years to regain size of original 45 diameter root system The root system of the smaller tree will have become nearly as large as that of the 10 inch tree after this 13 year period. Roots for both large and small trees grow at the rate of ~18 annually Tree Survival Transplant Shock (cont) During the root growing period, trees need a consistent source of water and nutrients Overwatering must be avoided Results in oxygen saturation and shallow root growth Ensure the margins of the transplant hole are loose Helps enable roots to move into adjacent soil Tree Survival Transplant Shock (cont) How do trees respond to water stress? Reduced stem trunk and root growth Damage to branches and crown Sudden death Signs may not be immediately evident 5
Tree Maintenance Tree Maintenance Watering Proper watering for good turf grass growth can compliment healthy tree root growth Deeper and less frequent watering can encourage healthier root growth for both turf grass and trees Surface soak into root ball (vertical watering) Sprays or drip emitters into mulch area around trunk Direct watering in root area including root ball and adjacent soil (horizontal watering) Emitters with root watering devices Tree Maintenance After Transplant Regular irrigation cycle ~ 3x weekly Applied to the root ball with 2-3 gallons of water for each caliper inch of tree Avoid over watering Many implement no artificial watering after year 3 No pruning for the first year after planting Pruning can inhibit root establishment and growth Pruning should have taken place at the nursery Maintain the mulch area around the root zone Prevent grass or weeds close to the tree trunk 6
Tree Maintenance Soil Compaction Heavy equipment passing on top soil can squeeze out up to 60% of the water by elongating roots Other causes can be pedestrian traffic and material storage Root rarely recovers Exaggerated in times of drought Establish traffic free zone around the critical root zone Minimize damage and maximize tree health Tree Maintenance Cost of Not Managing Root Growth In California, as much as $2 per capita is spent on expenses related to conflicts between tree roots and infrastructure Repairs (60%) Legal remedies (40%) Roots need to be drawn deep underground to avoid damage to hardscapes Tree Maintenance Soil Compaction Vertical mulching helps alleviate soil compaction 2 diameter hole, 12 deep, 8 feet from the tree trunk out to the edge of the critical root zone Holes are then back filled with pea gravel to allow water and oxygen to penetrate the soil Apply a 3 to 4 layer of high quality organic soil over the critical root zone Improves soil texture, moisture retention, increase soil fertility and weed control Identify the critical root zone to prevent high traffic flow 7
Root Watering Series Product Benefits & Features Benefits Investment Protection Deep and broad roots yield transplantation survivability, stability in high winds, fast and healthy growth Watering Efficiency Subsurface irrigation minimizes run-off and evaporation Landscape Aesthetics Installs at grade and minimizes damage to hardscapes Features Subsurface bubbler Trains roots away from surfaces and hardscapes Helps minimize surface erosion Reduces waste due to runoff with RWS without RWS 8
Features (cont) Minimizes transplant shock Water directed to root ball as well as where the roots need to be in a few years Supplements top-down soaking Helps ensure root integrity and better tree growth 2 Growing Seasons w/ RWS 9 Growing Seasons w/out RWS Features (cont) Rigid tube design Mesh material allows for horizontal movement of water into root zone and surrounding areas Supports pea gravel fill to strengthen tube against root compression and to help disperse water 36 version with non-potable grate cover Features (cont) Connects to traditional irrigation lateral lines Integrated polyethylene swing assembly connects to PVC and PE pipes Supports low-volume tubing Can be ordered without a swing assembly or spiral barbed fittings to allow direct connection to a drip system Top View (grate removed) 9
Features (cont) Installs even at grade level Aesthetically pleasing appearance Helps minimize personal injury; e.g., tripping, by eliminating above ground risers and pop-up strays with RWS without RWS Features (cont) Self-contained and factory assembled Swing assemblies and spiral barb fittings simplify attachment to lateral pipes Better reliability and quality than self-assembled units Sand sock option Prevents sand particles from penetrating the RWS tube Available on the 18 and 36 models Features (cont) Locking grate cover Deters vandalism Available on the 18 and 36 models Purple reclaimed water grate cover option Available on the 18 and 36 models 10
Features (cont) Comes pre-assembled in (3) sizes Provides design flexibility Accommodates all tree & shrub sizes Saves time and money by being ready to install out of the box RWS (36 x 4 ) RWS Mini (18 x 4 ) RWS Supplemental 10 x 2 Features (cont) Bubbler options Most models come with pre-installed bubbler options Flow range 0.25-2.0 g/m (1.2-7.2 l/m) Provides optimal watering Helps avoid overwatering Check valve options Prevents water from draining out of system when watering is not occurring Reduces erosion and run-off Installation Installation flexibility Typically 2-3 RWS per tree beyond root zone at edge of tree canopy Optionally, add additional RWS further away from trunk to accommodate future growth Ideally, place RWS on separate watering zone Units placed beyond root ball 11
Specifications RWS bubblers RWS: 0.25 g/m (0,95 l/m), 0.5 g/m (1,9 l/m), 1.0 g/m (3,8 l/m), 2.0 g/m (7,6 l/m) RWS Mini: 0.25 g/m (0,95 l/m), 0.5 g/m (1,9 l/m) RWS Supplemental: 0.25 g/m (0,95 l/m) RWS tubes RWS 36 x 4 (91 x 10 cm) RWS Mini 18 x 4 (46 x 10 cm) RWS Supplemental 10 x 2.3 (25 x 6 cm) Ordering RWS RWS-B-C-1401 RWS-B-1401 RWS-B-X-1401 RWS-B-C-1402 RWS-B-1402 RWS-B-C-1404 RWS-B-C-1408 RWS (6 units per package) RWS-Mini RWS-M-B-C-1401 RWS-M-B-1401 RWS-M-B-C-1402 RWS-M-B-1402 RWS-M (12 units per package) RWS/RWS-Mini other RWS-SOCK RWS-GRATE-P (6 units per package) RWS-Supplemental RWS-S-B-C-1401 RWS-S-S Ordering (cont) (20 units per package) 12
Root Watering Cases Oregon Site #1 with RWS Year 1 Year 3 Oregon Site #2 with RWS Year 1 Year 3 13
Florida Site with RWS Royal Palms Planted with RWS at Dolphin Stadium Miami, Florida Major Sites Using the Rain Bird Root Watering Series Tian anmen Square, Beijing China (1,200 RWS Units) State Veteran s Cemetery Boise, Idaho (1,200 RWS Units) Greek Town Casino, Downtown Detroit, Michigan (80 RWS Units) Zaragoza World Expo 2008 Aragon Spain (66 RWS Units) RWS Benefits to Specifiers 14
Specifier Benefits Investment Protection Tree survivability Tree appearance Watering Efficiency Use less water Operate under water rationing Landscape Aesthetics Minimize run off Minimize hardscape damage cause by roots Sources Sources Best Management Practices for Successful Urban Tree Plantings; Dr. Ken Tilt and Dr. Joe Eakes, Auburn University Horticulture; David West, James Miles, and William East, Alabama Cooperative Extension System; http://www.ag.auburn.edu/hort/landscape/hurricane_bmps2.html Newly Planted Street Tree Growth and Mortality; David J. Nowak, Joe R. McBride, Russell A. Beatty; College of Natural Resources, University of California Berkeley; Journal of Arboriculture, 16(5): 124-130, 1990 (now the International Society of Arboriculture s Arboriculture & Urban Forestry journal; http://nrs.fs.fed.us/pubs/jrnl/1990/ne_1990_nowak_001.pdf Providence's Urban Forest; Brown University; http://www.brown.edu/research/envstudies_theses/summit/briefing_ Papers/Greenspace_Openspace/Urban_Trees.html State of Providence s Urban Forest Report, April 2008, http://forestry.providenceri.com/forestry/docs/state_of_providences_ Urban_Forest_2008.pdf 15
Sources (cont) Trends In Street Tree Survival, Philadelphia, PA; Lara Roman, University of Pennsylvania; May 2006; http://repository.upenn.edu/mes_capstones/4/ Vertical Mulching; Athens-Clarke Country Georgia; http://www.athensclarkecounty.com/documents/pdf/landscape_ management/tcn_vertmulch.pdf Soil Compaction Impacts On Tree Roots; Dr. Kim D. Coder, University of Georgia; July 2000; http://warnell.forestry.uga.edu/service/library/for00-008/for00-008.pdf Various issues of The Arboriculture Journal and Arboriculture & Urban Forestry Journal The Arboriculture Journal (1975-2005, Volumes 1-31) became the Arboriculture & Urban Forestry Journal (2006-present, Volumes 32- present) Sources (cont) Irrigation Systems & Trees; UMass Extension; http://www.umassgreeninfo.org/fact_sheets/plant_culture/irriga tion_sys_and_trees.pdf Transplant Shock: Severity Dependent on Tree Size and Restoration of Root-Shoot Balance; Dr. Gary Watson, Morton Arboretum; http://www.dnr.state.mn.us/fid/may97/transhck.html The Impact of Soil Compaction on Soil Aeration and Fine Root Density of Quercus palustris; Gary W. Watson, The Morton Arboretum, and Patrick Kelsey, Christopher B. Burke Engineering, Ltd; http://www.mortonarb.org/images/stories/pdf/research/watson/ soil_compaction.pdf Treating Soil Compaction Near Trees; E. Thomas Smiley, Plant Pathologist, Bartlett Tree Research Laboratories; http://www.groundsmag.com/mag/grounds_maintenance_treating_soil_compactio n/ Sources (cont) Soil Compaction: Cause, Effects, and Control; University of Minnesota Extension; http://www.extension.umn.edu/distribution/cropsystems/dc311 5.html Tree Root Growth Requirements; Dr. Kim D. Coder, University of Georgia; July 2000; http://www.snca.org/enviro/trees/pdfs2/treerootgrowth.pdf Tree Roots - Where Are They?; Alan McDaniel, Department of Horticulture, Virginia Tech; The Virginia Gardener Newsletter, Volume 6, Number 8; http://www.msue.msu.edu/objects/content_revision/download.c fm/item_id.207976/workspace_id.- 30/OC0478%20Tree%20Roots%20Where%20are%20They.pdf/ 16
Sources (cont) Dead Branches, Dead Tops & Dead Trees: The Interaction of Water Stress, Insects & Disease; Forest Health & Monitoring Unit, Oregon Department of Forestry; http://www.oregon.gov/odf/privateforests/docs/fh/interactiono fdrought.pdf Effects of Regulated Deficit Irrigation Under Subsurface Drip Irrigation Conditions on Vegetative Development and Yield of Mature Almond Trees; Plant and Soil Journal, Volume 260, Numbers 1-2 / March, 2004; Pascual Romero, Pablo Botia and Francisco Garcia; http://www.springerlink.com/content/t2437q7g067un726/ Costs Due to Conflicts. Between Street Tree Root. Growth and Hardscape; E. Gregory McPherson and Paula J. Peper, Western Center for Urban Forest Research; http://www.fs.fed.us/psw/programs/cufr/.../cufr_109_em00_81.p DF International Mycorrhiza Society; http://www.mycorrhizas.org/ Questions? Jeff Hayes jhayes@rainbird.com 17