Leaves reduce the velocity of raindrops Leaves prolong the duration of rain while slowing the rate Much rain evaporates from leaves without reaching the soil Rain dripping from trees is buffered by leaf litter Much of the rainfall is absorbed by tree roots and transpired back to the atmosphere Soil is stabilized by tree roots and surface litter Porous soil beneath trees absorbs and retains groundwater, minimizing runoff
Stabilization: Rainfall penetrating the canopy is cushioned by leaf litter, and seeps slowly into soil that is held in place by a mesh of fine roots.
Filtration: Forest soils are rich with life. Soil- dwelling organisms and roots keep the soil porous and able to absorb rainfall or runoff.
Forest soils retain water in soil pores. Water not absorbed by plants can infiltrate and recharge ground water reserves. Runoff from forest soils is minimal.
During development, topsoil and tree cover are removed…
Rainfall + Unprotected Soil = Sedimentation and Degraded Water Quality
Even well-landscaped lots lack the leaf surface, porous soils, and root mat needed to intercept, filter, and retain rainfall and on-site soil.
Lake Greenwood’s fish and wildlife depend on tree cover and water quality.
In forestry operations, forested buffers called streamside management zones have proved very effective at preventing soil movement from areas disturbed by logging.
Likewise, forested buffers along lakefronts and drainages can prevent water quality problems from runoff during development.
Engineering solutions such as retention ponds, constructed wetlands, and silt fencing (when properly installed) are valuable tools along with forested buffers.
Trees and native landscaping enhance the value and marketability of homes.
“Several studies have analyzed the effects of trees on actual sales prices of residential properties. Homes with equivalent features—square footage, number of bathrooms, location—are evaluated. In one area a 6% increase in value was associated with the presence of trees; an increase of 3.5 to 4.5% was reported in another study.” University of Washington Center for Urban Horticulture November, 1998
The aesthetic qualities of the Lake Greenwood community can be preserved and enhanced by intelligent protection and preservation of trees and the native understory.
Tree Protection During Development (Dead Tree) (Doomed Trees)
Trees naturally grow in groups, interspersed with native grasses and shrubs. Trees should be saved in groups, with associated understory plants, where possible.
It’s not practical to protect the entire root zone in most cases, but if trees and understory plants are to survive and thrive, the critical root zone of the tree must be undisturbed. The CRZ is defined as a radius of one foot per inch of tree diameter (breast height). PROTECTION
THE ROOTS MUST NOT BE HARMED TRUNK DAMAGE MUST BE AVOIDED SITE CHANGES SHOULD BE MINIMIZED
When possible, site the structures, paving, and utilities on the lot as far from the trees (and their roots) as possible.
Where equipment must operate beneath trees, a bridge or a thick blanket of mulch can prevent soil compaction and root damage.
Cut and fill can be fatal to trees. Retaining walls can be used to protect the critical root zone.
Locating buried utilities outside the critical root zone is best, but tunneling can be used to route utilities beneath trees.
Non-standard construction methods, such as using posts, pillars or I-beams rather than foundation walls or slab on grade, can minimize damage to nearby trees and undergrowth.
Lawns, flower and shrub beds, irrigation, and other landscaping can destroy roots as effectively as other construction activities.
The bottom line: to protect trees, stay away from them! Remember, the critical root zone is a radius of one foot per inch of tree diameter. Keep this area undisturbed, and the trees will survive and prosper.
Have a Plan A tree plan would include a site evaluation to identify trees for preservation, a plan to preserve them, and a planting plan if it’s not practical to save existing trees.
A tree plan should be ideally be prepared by a trained arborist, but with proper guidelines, almost anyone can be trained to prepare an adequate tree plan for a building site.
National Standards for tree protection during construction were published in 2005
GETTING HELP Use a forester or certified arborist with training and experience in tree protection Use literature and guidance readily available on the Internet and in printed form Get training for company personnel in tree protection techniques National Arbor Day Foundation SC Forestry Commission US Forest Service