When the National Park Service and the Korean War Veterans Memorial Foundation undertook refurbishment of the Korean War Veterans Memorial and constructed the Korean War Memorial Wall of Remembrance on the National Mall in Washington, D.C., WSSI provided tree preservation consulting services.
The Challenge
Extending the circular plaza around the original Pool of Remembrance, installing two new pedestrian paths, and refurbishing the grounds that are home to 19 eight-foot tall statues representing an advance party from Korean War posed a variety of risks to the good health of the mature trees established in the memorial.
Our Solution
To gain a clear picture of tree presence and health, WSSI urban foresters conducted assessments and worked closely with the National Park Service to ensure best management practices for the trees that are a part of this national landmark.
Prior to construction, WSSI’s International Society of Arboriculture certified arborists conducted a site assessment with individual Level 2 Tree Risk Assessments to accurately determine tree health with visual assessments, mallet sounding, and decay probing. That information allows WSSI to prescribe the best stress reducing measures to be taken during construction.
During the investigation, WSSI staff determined which trees met the District of Columbia definitions for Heritage and Special designations and protections.
WSSI’s consulting arborists conducted a subsurface root investigation study to compare the proposed site concept design with the extent of tree root growth. Using a Supersonic Airtool, WSSI staff moved porous soils away from non-porous roots, gently exposing them for assessment, and allowing our team to depict root length, depth, and health, and utilize that information to inform design and construction decisions.
Our tree preservation plans overlaid proposed design elements with graphic depictions of the Critical Root Zones and Structural Root Zones and were provided to the design team in CAD format, allowing seamless integration with the overall site plans.
The plans allowed for construction modifications to address adjustments to the decorative stone, irrigation, and drainage improvements, with a goal to maintain tree health while providing pedestrian access at the memorial site.
WSSI’s urban forestry staff were present during construction to coordinate a proactive strategy with the construction managers that involved equipment, access, staging, and stockpiling. Soil decompaction and amendments boosted tree health and resiliency in the grove that shelters the soldier sculptures. Temporary root protection mats were also installed to provide additional shielding for tree roots. We subsequently provided monitoring during the post-construction first growing season.
Project Facts
- Owner
National Parks Service - Location
Washington, D.C.