are valuable tools along with forested buffers.

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Transcript are valuable tools along with forested buffers.

Treading Lightly on the Shore
The Role of Residents and Developers in Keeping
Lakes Healthy
The Role of Trees in Preserving the
Quality of Lake Greenwood
•Water Quality
•Fish and Wildlife
•Economic Values
•Aesthetic Quality
Trees and Water Quality
Trees and understory plants have a
tremendous effect on what flows into
our lakes and rivers:
•Interception
•Stabilization
•Filtration
•Storm water retention
Interception: It’s all about
surface area.
•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. Soildwelling 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.
(Dead Tree)
(Doomed Trees)
Tree Protection During Development
What does it take to
SAVE A TREE?
FLAGGING TAPE HAS NEVER
SAVED A TREE.
There’s more to a tree…
…than meets the eye!
Roots typically occupy the
upper few inches of soil,
and can extend a distance
of three times the height of
the tree.
TREES ARE SAVED OR LOST
BEFORE THE FIRST PIECE OF
EQUIPMENT MOVES ON TO
THE PROPERTY.
It’s too late now…
these trees are goners!
The soil is compacted…
and the roots are destroyed.
TO SAVE TREES, IT TAKES:
•EVALUATION
•PROTECTION
•MONEY
EVALUATION
•SPECIES
•LOCATION
•HEALTH
•SOUNDNESS
•STRUCTURE
•PRACTICALITY
DESIRABLE SPECIES
•OAKS
•DOGWOODS
•BLACKGUM
•MAPLES
•SYCAMORE
•REDCEDAR
•ELM
•HICKORY
LESS DESIRABLE
SPECIES
•PINES
•TULIP-POPLAR
•SWEETGUM
•COTTONWOOD
EVALUATION
•Choose trees that
allow room for
construction and
utilities.
•Trees must have room
to grow to maturity
without causing
problems.
•Choose trees that will
enhance the property.
(bad choice)
EVALUATION
•Choose trees that are
free from decay and
diseases that will limit
their useful lifespan,or
create hazards.
GOOD STRUCTURE AND FORM
STRAIGHT
SINGLE TRUNK
CAVITY-FREE
FULL CANOPY
POOR CHOICES
•MULTIPLE TRUNKS
•FORKS
•CAVITIES OR
DECAY
•LEANS
•DIEBACK
Trees naturally grow in groups, interspersed
with native grasses and shrubs. Trees
should be saved in groups, with associated
understory plants, where possible.
PROTECTION
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.
PROTECTION
Fencing is
crucial…
PROTECTION
Fencing is
crucial…
…and a
Rottweiler
helps.
Signs can help
get the
message
across to
subcontractors
Plastic mesh gets no respect…
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