Correspondence /y /
w7 Walter H. Knapp & Associates, LLC
Consultants in Arboriculture, Silviculture, and Forest Ecology
MEMORANDUM
DATE: September 5, 2012
TO: Albert Shields (City of Tigard)
CC: Steve Lucas (Legend Homes)
FROM: Morgan Holen, Project Arborist
RE: Walnut Creek Subdivision, Lot 12 — Tree Protection Recommendations
At the request of Legend Homes, I visited Lot 12 at Walnut Creek Subdivision in Tigard on
September 4, 2012 in order to determine recommendations for tree protection during
construction. A marked up site plan is enclosed and recommendations are provided below.
Approximately eight trees are'- located on the adjacent property just north of Lot 12. The crowns
of these trees extend a maximum` of approximately 13 -feet across the property line, overhanging
the project site. Pruning for building clearance does not appear necessary. The standard tree
protection area is 15 -feet from the back of the lot to the property line fence (highlighted in purple
on the enclosed site plan). For Lot 12, the protection area may be reduced to 8 -feet from the
property line fence to allow for deck construction while continuing to provide adequate tree
protection (red line illustrates recommended tree protection area).
Invasive vegetation and the uppermost organic matter may be removed from the protection area
by hand and with hand tools. Protection fencing (orange silt fencing on wooden stakes) shall be
installed and verified by the project arborist prior to construction and monitored at least once
every two weeks with inspection reports sent to the client, contractor and city.
Deck construction shall be performed under the guidance of the project arborist. This work shall
be conducted by hand and no equipment is allowed within the tree protection area. Decks will be
built on pier blocks and concrete footings measuring approximately 18 "x18 "x18" are needed to
hold the pier blocks in place; excavation for footings shall- be conducted by hand- digging. The
location of concrete footings shall be adjusted to avoid root impact as feasible. If root impact is
unavoidable, roots less than 2- inches in diameter may be cut clean to the edge of excavation with
a pruning saw or pruning shears; if the roots are larger than 2- inches in diameter, work shall
temporarily stop so that the project arborist may be contacted for additional recommendations.
No storage or stockpiling of materials is allowed within the protection area. Concrete for
footings should be mixed in a wheel barrow on site.
Please contact us if you have questions, concerns, or need any additional information.
Morgan . Holen
Morgan Holen & Associates, LLC
ISA Certified Arborist, PN -6145A
ISA Certified Tree Risk Assessor, PN- 449
Enclosure: Site Plan Markup 9 -5 -12
7615 SW Dunsmuir Lane, Beaverton, OR 97007
Phone: (503) 646 -4349 Fax: (503) 747 -4863
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