Reuse of Wood and Snag Policy
Purpose
Woody debris is an important part of forest and stream ecosystems for its role in sequestering carbon and nutrient cycling, a source of energy for aquatic ecosystems, providing habitat for terrestrial and aquatic organisms, and contributing to structure and roughness, influencing water flows and sediment transport. Leaving wood in place also conserves fuel, can reduce damage to parks and soils from heavy equipment, conserves staff resources, and reduces strain on our waste management system.
Trees are to be reused wherever possible: dead trunks (snags) are left standing in wooded areas for use by cavity-nesting animals and birds; long branches can be used as trail edges in some parks; and some tree trunks can be left standing to be carved into sculpture or other art objects.
Snags
Standing, usually dead, tree trunks, or snags, provide habitat for woodpeckers and insects, and can remain for decades, if planned correctly.
In natural lands and Natural Resource Conservation Areas (NRCAs)
Snags should be kept, as much as possible, where it is safe for the surrounding uses and for the operator creating the snag. The height of the snag should be no taller than the nearest constantly or frequently occupied location (people, buildings, or other property. For example, a 15 ft. snag should be at least 15 ft. from a paved trail or a shelter). Spaces, such as paved trails may be less frequently occupied (occasional or rare), and a 10-15 ft snag near those features may be acceptable, if residual risk is low. Risk is determined by an Urban Forester or tree maintenance supervisor. Natural lands and NRCAs can be found in Geocortex.
Near playgrounds, trails, buildings, managed/mowed landscapes and active recreation sites
Snags require approval from the Park Manager, where there is an overriding public education or public art goal, and the risk of failure and impact of the snag is low.
Coarse Woody Debris
Naturally fallen branches, bark and toppled trunks, as well as felled wood, hold a reservoir of nutrients which are gradually released into the woodland floor as they decompose. Once they're unlocked, these same nutrients can be reused by living trees and other plants for new growth, and carbon can be stored back in the soil. Coarse woody debris should be kept where possible, or moved to a nearby natural area.
In natural lands and Natural Resource Conservation Areas
Coarse woody debris should be left in the natural area in all situations, unless a clear risk to public safety or disease vectors exist from its presence, or if it significantly impacts sensitive ecosystems. Wood should not be moved, or as little as possible, to avoid additional damage. The Park Manager can request removal, if this risk exists, or if trails are impacted, according to the following:
- All paved trails should have 2 feet (4 ft preferred) of area from the edge of the pavement, clear of coarse woody debris.
- All unpaved trails shall be kept clear to the edge. Logs can be used to better define unpaved trail edges, or block unapproved informal trails
Near playgrounds, managed or mowed landscapes, and active recreation areas
All coarse woody debris shall be removed from these areas, and processed appropriately, unless an overriding public education, erosion control, or public art goal exists. Where nearby natural areas exist, wood may be moved to delineate their edge.
In streams and waterways
Small amounts of deadwood may be acceptable in a waterway, without causing a flood risk. Coordinate with the County flood risk manager to determine whether coarse woody debris needs to be removed from the waterway.
Urban Wastewood Reuse
Outside of Natural Lands, wood may be appropriate for urban wastewood reuse. If facilities, resources and the opportunity exist, consider processing urban wastewood in these facilities.
Resources:
Examples