The following Refuge 20/20 post was written by Chris Collins and Curtis Helm of the Lower Columbia Estuary Partnership.
More Than One Life to Live
If you’ve passed by Steigerwald Lake National Wildlife Refuge lately, you may have seen some trees gone. It’s true, but it’s only a small part of their life story.
An unfortunate but necessary part of restoring a more natural hydrology to this area, profoundly altered decades ago, is that some established trees were growing in areas that will become a stream channel or other feature. Where it is unavoidable, crews are removing trees. That is when their second life begins–nearly all trees removed are being salvaged to be used as habitat logs placed throughout the project site.
In addition to trees, the crew is relocating other shrubs and plants, like these ferns. Photo courtesy of the Lower Columbia Estuary Partnership
A Thoughtful Approach
We love trees and it was important to remove as few of them as possible. While designing the project, the design team continually analyzed and tweaked the project’s disturbance footprint to minimize the loss of mature trees and shrubs. As the project is constructed, USFWS and Estuary Partnership staff have been working closely on site with the contractor to ensure we are limiting further tree removal where we can. This close coordination has saved over twenty mature trees and countless smaller trees and shrubs. Additionally, many understory plants, such as ninebark, elderberry, and swordferns, are being salvaged, replanted, and watered in protected areas.
The most significant tree removal so far was north of SR14, to make way for realignment of Gibbons Creek. Around 30 trees were removed here, primarily cottonwood, alder and non-native cherry. This stand also included many dead and dying trees that had been overwhelmed by invasive English ivy, which we are removing, root mass and all, and disposing of at a landfill. A second area of trees were removed to create the path for one of four new floodplain channels, which ultimately will reconnect the site directly to the Columbia River.
Trees removed North of SR-14, like this cottonwood, are making way for a realignment of Gibbons Creek, seen to the right of the image. Photo courtesy of the Lower Columbia Estuary Partnership
A third area of cottonwood trees will soon be partially removed to make way for the west setback levee. This particular stand, located in the southwest corner of the refuge, is home to a great blue heron rookery, so no disturbance is allowed until this year’s chicks have fledged. This stand has a special place in the hearts of many visitors, and we do not take it lightly that approximately 20% of it must be removed. But we know that great blue heron are highly adaptable birds and that they choose a new nest from year to year, and numerous other rookeries occur along the river. We’ll also delve into the many ways the project will benefit birds and other waterfowl in a future blog post.
The crew carefully places removed trees into the new stream channel. Most of the removed trees will be given a second life in the project. Photo courtesy of the Lower Columbia Estuary Partnership
Trees are removed root-wad and all, as it all provides valuable in-stream and flooadplain habitat for wildlife. Photo courtesy of the Lower Columbia Estuary Partnership
These woody debris placements will create new habitat for macroinvertebrates, perches for birds, and resting spots for fish. Photo courtesy of the Lower Columbia Estuary Partnership
Removed Trees Form a New Kind of Habitat
Although the loss of some living trees is unavoidable, all trees are salvaged intact (including their root wad) and will have a second life as habitat logs placed throughout the restored wetlands and floodplains. These logs will provide cover for herptiles and macroinvertebrates, perches for raptors, and refuge for fish during high water events. They also become nurse logs as they decay.
And these trees will be replaced. Eventually, 400,000 native trees and shrubs will be planted by crews, volunteers and students as part of the project, including 120,000 trees and shrubs already planted last winter on Gibbons Creek’s 54-acre alluvial fan. Over 1,000 of these were 8-foot-plus cottonwood poles. A study of cottonwoods performed on Lady Island (near Camas) found that 9-year-old trees averaged 49 feet in height and almost 7 inches in diameter! They are remarkably fast growers on good sites and many parts of Steigerwald provide ideal soil conditions.
Though some trees must be removed for this restoration project, we are confident that the over 200 acres of new native plantings will more than make up for the losses during construction. We’re also thankful for our contractors, Rotschy, Inc. and LKE Corporation, for being dedicated to the spirit and goal of this project and working with us every step of the way to minimize harm to the natural resources valued by our community.