AGNEW — For Olympic National Park restoration botanist Joshua Chenoweth, the Elwha River dams removal project is as much an experiment in bringing back native grasses, shrubs and trees as it is in returning historic stocks of fish species.
“We’re trying to steer it and learn as we go,” said Chenoweth, who has been with the park for 10 years working on other projects.
“We will monitor up to 320 plots to tell us what’s working.”
Since 2006, he has been primarily focused on helping to oversee the five-acre native plant nursery at Clallam County’s Robin Hill Farm Park south of Pinnell Road in the Agnew area, between Port Angeles and Sequim.
The native plant center is named for Matt Albright, the park greenhouse manager who was on the ground floor of managing river revegetation before he died of cancer in 2007.
The 7-year revegetation project has a $5 million budget.
The nursery produces 80 species of native plants and trees in various stages of growth and will also grow grasses and forbs on a fresh-plowed site at the center.
About 5,000 pounds of grass and forbs seed are being planted at the nursery and on the revegetation sites already under way at the two lakes due to disappear with the return of the wild river — Lake Mills and Lake Aldwell.
About half of the 420,000 native plants and trees needed to revegetate 438 acres at Lake Mills and 340 acres at Lake Aldwell are being grown at the park’s greenhouse and nursery, with the other half being grown at Fourth Corner Nurseries in Bellingham, Chenoweth said.
Nothing will be planted or disturbed within 150 feet of existing forestland, he said, a buffer zone expected to reseed itself to the historic floodplain, which is already visible where lake waters have drawn down.
Seeds for growing plants were pulled from “seed banks” in the park and adjoining Olympic National Forest.
Planting to begin
Planting starts in earnest next month.
“This fall, we are going to put in over 20,000 plants,” Chenoweth said, naming a few, such as red alder, bigleaf maple, thimble berry, salmon berry, twin berry, snow berry, trailing blackberry, willows and cottonwood trees.
The first planting will be mostly around the present Lake Mills behind Glines Canyon Dam.
Non-native plants
The dams at both lakes were opened to draw down, and Chenoweth said that was timely for the seeds naturally drifting off cottonwoods and willows.
“We called it the luck of the drawdown,” he said, adding that among he and his colleagues, “that’s a joke.”
Chenoweth said he and other park scientists toured the shoreline of the receding Lake Aldwell on Tuesday and found some native plants, such as willows and cottonwoods.
Non-native plants have already sprouted and will be pulled or treated by revegetation work crews.
“One we’re worried about coming up is reed canary grass,” he said.
Canada thistle and herb Robert, or “stinky Bob,” are also popping up and throwing down their invasive root systems, which are difficult to eradicate.
At Lake Mills, Chenoweth said, Scotch broom and St. John’s wort have sprouted.
Low-toxicity herbicide approved by the Environmental Protection Agency will be made in batches to use around the lake sites where needed.
Lower Elwha crew
A noxious-weed crew of four people from the Lower Elwha Klallam tribe will be hard at work in the war on non-native species as they arise.
Chenoweth has a list of at least 150 weeds that seem to thrive in disturbed areas of the watershed.
Much of the seed for new native plants is further cleaned and prepared at the native plant center, then planted in flats for sprouting at the greenhouse.
The greenhouse has long elevated metal beds with water-heated tubes that run under plant flats to promote root growth.
Mimic nature
One way man mimics nature occurs before sprouting starts at the greenhouse, Chenoweth said.
Seeds are placed in peat and refrigerated to mimic winter for up to two months.
“After that, they are ready to sew in flats,” he said.
Part of the plan is to get plants started on the dry terraces left behind when the water recedes.
That will help stabilize the slopes and reduce erosion.
Chenoweth, for his master’s degree, conducted studies to discover if seeds in the reservoir would sprout on their own and grow into plants.
He found no viable seeds in the area underwater.
He expects grasses to establish themselves quickly.
Monitoring plants
Careful monitoring will help him change planting strategies as necessary.
The primary goal is to get native plants growing as quickly as possible.
After the completion of the dams removal in the fall of 2013, he said, “We’ll go like gangbusters” with a National Park Service crew of six at Lake Mills and a Lower Elwha Klallam tribe crew of three at Lake Aldwell.
Once the plants are trucked over to the sites, he said, “we’re going to try to walk them in or use [utility terrain vehicles] to tow them in.”
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Sequim-Dungeness Valley Editor Jeff Chew can be reached at 360-681-2391 or at jeff.chew@peninsuladailynews.com.