The goal of many revegetation projects is often almost heroic: to recreate a wetlands damaged by open-pit coal mining, a salt water marsh drained for farming, or a canyon eroded by wildfire and flood-all based on tiny native seeds.
Often these sites require compost, fertilizer, and mulch. In addition to mulches that are blown dry and protect the seeds, some are applied hydraulically, and some contain nutrients for the soil. Some newly developed mulches do both.
Coal Mine Reclamation Project
The reclamation of Pit 548, mining permit No. 16920107 in Clarion County, PA, shows how one coal mining operation went far beyond its permit requirements and turned a large open-pit mine into a beautiful and functional wetlands.
“Wetlands play a huge role in wildlife habitat, diversification, and sediment and erosion control,” says Daniel Fescemyer, president of RFI Inc. in Sligo, PA. RFI produces coal in Clarion County and delivers coal to industrial customers in Pennsylvania and New York.
“I love fixing this stuff up and making it better. I have kids and grandkids, and I want them to see a better world.”
As part of its permit, RFI was required to construct 2 acres of wetlands for every acre affected by the mine, for a total of 7.1 acres: 2.35 acres of emergent wetlands, 4.35 acres of forested/shrub wetlands, and 0.4 acre of open-water wetlands. According to a 2012 post-construction audit required by the Pennsylvania Department of Environmental Protection (DEP), RFI built a total of 11.55 acres, exceeding the requirement by 4.45 acres.
“This company and its reclamation efforts are pretty unique,” Fescemyer says. It has won national awards for its reclamation and revegetation program.
The site, in a valley with a stream that flows through it most of the year, once had significant wetlands created by springs along the stream and at the beginning of the stream. Much of it was surrounded by forest.
The new wetlands are designed to provide a diverse habitat for wildlife and to be inaccessible to people. Low rolling hills lead to emergent wetlands up to 2 feet deep. They’re dotted with hummocks planted with shrubs and trees for wildlife habitat. In the centers are very deep pools designed to create isolated habitat for waterfowl. One is 1.4 acres of open water. They’re still fed by the springs.
The revegetation was done using seed from the site, as well as wetland seed mixtures and cuttings for shrubs from Ernst Conservation Seeds in Meadville, PA.
“Calvin Ernst has helped me a lot over the years,” Fescemyer says. “The company is very well versed in wetland mitigation. They’re very reputable, and very good at what they do.”
Before the mining began, RFI excavated a large amount of undisturbed topsoil and subsoil and stored them separately onsite to use for the reconstructed wetlands.
Because wetland soils are hydric-saturated with water either seasonally or permanently-they’re anaerobic and develop properties that are different biologically and chemically from those of aerobic soils. They have a good, neutral pH, and in addition they contain seeds from native vegetation. These seeds often germinate before introduced seeds because they’re already acclimatized to the soils and the environment.
The first step in the reclamation project was to build a drainage control system. All the drainage from the project went through sediment ponds.
The weather was a challenge, Fescemyer says. “You can’t have water and working equipment. We work year round, and we had quite a lot of storms.”
RFI temporarily removed the stream and graded the site to approximate the original contours of the valley. Crews built the wetland cells and shaped the hummocks and the deeper pools inside them with small equipment, lined them with clay or subsoil to make them impermeable, and then added topsoil. Because the area of the new wetlands is twice as large as the original, they had to import additional soil. They also rebuilt the stream through the valley.
“Usually you can’t build a stream through wetlands, because stream water is cold and wetland water is warm,” he says. “The water temperature affects the habitat.” In this case, however, a wetland preexisted at the head of the stream and the new one was recreated as it was prior to mining.
Crews amended the land around the cells by adding lime and approximately 300 pounds per acre of 15-15-15 fertilizer. “We worked the soils just like on a farm,” he says. “We did a lot of harrowing and grading with tractors to get the soil fairly smooth so we could drill-seed to get the cover around the site.”
The first seeds were planted in September 2009. They were supplemented in April 2010.
On the land around the cells, RFI planted Ernst’s Riparian Buffer Mix: grasses, fox sedge, clovers, and some legumes to provide cover for the other seedlings.
In the emergent wetland cells they planted Ernst’s Perennial Food and Cover Wetland Mix, which includes wild rye, sedges, reeds, deer tongue, and nodding bur-marigold.
The size of the wetland seed was a challenge. “Wetland seed can be so small you can hardly see it,” Fescemyer says. “You have to sow it by hand. But once you get it in the ground, it grows in really fast.”
The doves and geese created havoc with it, he says, and at times RFI had to reseed. Once a cell was seeded, crews added water immediately to promote faster germination and minimize seed losses from the birds.
On the mounds, they hand planted with Ernst’s Shrub Mix, which contains arrowwood, three varieties of dogwood, spicebush, witch hazel, buttonbush, and elderberry. Then they hydroseeded with the Riparian Buffer Mix to help cover the larger shrub seed and promote quick growth of the herbaceous plants.
By the October 2012 audit, the hydrology of the wetlands was stable and they were functioning as planned.
As expected, the first seedlings to appear in the emergent wetland cells were native volunteers from the original soils. These included narrow-leaved cattails, spike rush, soft rush, reed canary grass, and rice cutgrass. Species from the introduced seeds in the emergent wetlands and the open-water pool also were establishing themselves.
Growing the woody species from seed was a challenge. Although some of them, notably swamp oak, red cedar, elderberry, and gray dogwood, established themselves, they’re “notoriously slow” to propagate, according to the report.
In the spring of 2012, RFI hand-planted 1,100 live stakes of buttonbush, silky willow, shining willow, red osier dogwood, and elderberry to supplement them. The hand-planting was so successful that it had the potential to upgrade an additional acre of existing emergent wetland to forested/shrub status, according to the report.
“The project took a tremendous amount of work, but it’s doing really, really well,” Fescemyer says. “A lot of things can be accomplished when you do something like this. You create something that is better than what was there before.”
Highway 7 Canyon Restoration
In September 2013, not long after a wildfire had denuded the hillsides, a rain event some called a 1,000-year storm hit northern Colorado.
On the flat farm and ranch land, muddy rivers and creeks overflowed. They washed out bridges and several hundred miles of roadways and damaged several dozen homes in cities and towns, including Boulder, Lyons, and Longmont.
In the canyons, rain-saturated soil, boulders, rocks, and debris from the wildfire crashed onto the roads and into the raging water below.
“It was very devastating, one of the largest natural disasters since Hurricane Katrina,” says Megan Butts, president and CEO of Powell Restoration Inc. in Commerce City, CO.
Powell, a full-service seeding and erosion control contractor that does work for the Colorado Department of Transportation, the Colorado Division of Wildlife, municipal airports, and commercial buildings, revegetated a 15-mile-long section of a canyon on State Highway 7 South, near Lyons.
The general contractor, Skanska, an international construction company, had to wait weeks for the flooding to subside before it could begin to restore the face of the canyon and rebuild the section of road, she says.
“They contacted us the beginning of February. We started work the end of February and finished in the middle of March.”
Powell used seed from Granite Seed. “We use Granite Seed for all our seed,” Butts says. “We have to respond very quickly with seed. With storms coming in, we have to be ready. They are always extremely timely when we need custom seed. We can ask for several lots of seed in the morning and have it by lunchtime, and their pricing is very competitive.”
Because this was a federal project, the federal government provided the specifications. There was no requirement for soil amendments or for maintenance.
The 15-mile-long stretch varies from very flat land to cliffs with 2:1 slopes. Much of the canyon is 200 to 300 feet wide. The roadway is steep in places, she says. It hugs the slopes to the left. On the right is the St. Vrain River and, across that, slopes that can rise steeply back up again.
“Skanska did a great job of putting the mountain back,” she says.
Powell sprayed both sides of the canyon using two steps. Crews first hydroseeded with a custom hydromulch and a seed mix containing grasses, fescues, oats, penstemon, and black-eyed Susan. They returned to hydromulch with Flexterra High Performance-Flexible Growth Medium (HP-FGM) from Profile Products in Buffalo Grove, IL.
Flexterra forms a sticky blanket that temporarily stabilizes the slopes, and it keeps the seed in place, giving it a chance to germinate, she says.
As they drove up the canyon, the crews sprayed the slopes across the river, 150 to 200 feet away in some spots. On the opposing side, they sprayed straight up the slope beside the road, at times to heights of 50 to 60 feet.
That wasn’t the only challenge.
“Our winter is a constant battle with snow, and we still had issues at the end of February,” Butts says. “It snowed while we were seeding.”
In addition, the crews got soaking wet from working in the icy river. They used water from the river to spray, and the pumps froze. The lines in their hydroseeding equipment froze. “Once they started, they had to keep going, or the pipes would freeze,” she says.
This project will stabilize the slopes, she says. “It was one of those projects you don’t get to do very often. It was a great opportunity for us to work on something like this.”
Salt River Ecosystem Restoration
The Salt River used to be deep enough to allow oceangoing steamships to move up to Port Kenyon, some 4 miles inland from the Northern California coast and a mere 13 feet above sea level. Coho and Chinook salmon spawned in the river, and steelhead and coastal cutthroat trout thrived, according to the Salt River Watershed Assessment, a special project of the Coastal Watershed Planning and Assessment Program.
When farming began in the area in the late 1800s, the trees were cleared, and levees and cofferdams were built to drain the thousands of freshwater and saltwater tidal marshes of the delta. The farms’ alluvial soils washed into the river, the river’s drainage capacity decreased, flooding increased, and the fish disappeared.
“It’s my understanding that in 150 years or so the Salt River just silted in,” says Scott Miller, a family member and partner with Miller Farms Nursery, located in McKinleyville, CA.
The Humboldt County Resource Conservation District and a large number of entities, including the California Fish and Game Commission and Ducks Unlimited, participated in the design and funding of phase one of the Salt River Ecosystem Restoration Project.
The project, which began in May 2013, restored a former ranch to a 300-acre tidal marsh area. It also restored the first 2 miles of the Salt River, removing the cofferdams and building three tide gates. Fresh and tidal waters flow inland once again, enhancing fish habitat and migration conditions for the salmon.
In addition, sediment dredged from the Salt River channel was used to build a setback berm, or levee, approximately 2 miles long. It was topped with a gravel road. “It will encapsulate the high tides and reduce flooding,” Miller says. “It also establishes an access route to the property on the east side of the project.”
The landscaping and construction division of Miller Farms Nursery revegetated approximately 80 acres of the project, including the levee and disturbed land.
Crews used six different seed mixes from Pacific Coast Seed in Livermore, CA, much of which was collected by hand. “They’ve been around for a long time,” Miller says. “They’re probably one of very few companies who could have handled this.” David Gilpin, president of Pacific Coast Seed, put the seed blends together.
When Miller and his crew arrived early September 2013, Anderson Dragline, a full-service general engineering contractor in Gridley, CA, was setting the grades and prepping the seedbeds, as well as excavating the river and removing the cofferdams.
That was one challenge. “Once the cofferdams were removed, the Salt River started receiving water,” Miller says. “They had to dig through water.”
The second challenge was the tides.
“Anderson dug through all the tidal flows to remove the cofferdams,” he says. The process usually took approximately 12 hours. Anderson watched the tidal charts and worked as quickly as possible, starting at low tide, and Miller followed, hydroseeding as quickly as possible behind Anderson’s crews.
Often, they finished before the tide came in again. Occasionally the incoming tidal water left them only narrow trails to follow to the areas that had to be seeded. At times, it cut off their access, but Miller would find other routes to achieve the seeding process.
Still, Miller says, “I’m extremely happy. The nice part was working with Anderson. We helped each other.”
Anderson graded the berm from roughly 7.5 feet above sea level to the top of the levee road. “Typical high tides range from 7 to 8 feet,” Miller says. “There’s no sense seeding below high tide. The salt water will kill whatever is in there. Occasional high tides won’t hurt.”
On the sides of the berm, from 7.5 feet to the top of the road, they used native seed mixes that included fescues, brome, wild rye, achillea, and lupin. The slopes are gentle enough to drive equipment on, Miller says.
On the marshland, they used the same seed as above, as well as grass, angelica, and gridelia, which is favored by ducks. On the driest flat land, they used a pasture mix containing mostly clover and some ryegrass.
“Accessing parts of the site was a logistical nightmare,” Miller says. The method of application depended on the accessibility and the wetness of the ground. It almost always involved a three-step process.
Wherever the ground was dry enough to put a tractor, crews farm-seeded. They harrowed the seed and fertilizer in, blew straw on top, and then hydromulched with a tackifier to keep the straw down.
On areas that were too wet or narrow to farm-seed, Miller hydroseeded instead, blew straw on top, and then hydromulched.
Where the ground was too wet for the straw blowers, crews used only two steps: They hydroseeded, and then hydromulched with straw. In the wettest areas, they pulled their hydroseeding equipment with bulldozers.
In wooded areas near the river that were too difficult to access for maintenance, Miller spread wood chips from the riparian areas instead of seeding.
The revegetation was completed in January 2014.
GHD and Ducks Unlimited served as inspectors while the seeding was taking place and will monitor the site to ensure at least 70% survivability.
“Inspectors and contractors don’t always see eye to eye,” Miller says. “They were wonderful.”
He went back in March. “It was just beautiful,” he says. “Phase one has already restored the native habitat. It had geese, ducks, deer, foxes, coyotes, and raccoons after all the equipment was gone. This project was one of the best I’ve worked on in 30-plus years.”
In 2013, CalTrans awarded Selby’s Soil Erosion Control the contract to revegetate approximately 30 acres of land surrounding a new overpass near Tracy. It included dry, flat soil along Highway 132 and slopes as steep as 2:1 on the abutments of the new on and off ramps.
The CalTrans specification called for applying 1 inch of compost onto the soil and then hydroseed, but Jay Selby, the owner of the Newcastle, CA-based company, which does work on erosion control projects for landfills, new developments, gold mines, and levees as well as for CalTrans, had another idea.
Applying dry compost before seeding has its disadvantages. The application can be dusty. The compost can erode with wind and rain before the vegetation becomes established, and when it isn’t tilled into the soil, it doesn’t provide as many benefits as it could otherwise.
Applying compost hydraulically eliminates the dust and erosion. If the area is seeded, the fibers in the mix absorb up to 10 times their weight in moisture so the seed germinates faster, Selby says.
But Selby was determined to find an improvement to compost to shoot hydraulically, one that would be acceptable to CalTrans.
Ramon Godinez of Soil and Seed Solutions in Temecula, CA, connected Selby with Organic Earth Industries Inc. in Fort Collins, CO, a company that had developed a line of hydraulically applied erosion control products. Kevin Loucks, president and CEO of Organic Earth, recommended TerraVita, a hydraulic growth medium (HGM) and a US Composting Council-approved compost.
“They’ve had it for a few years now,” Selby says. “This is the closest hydraulically applied product that matches CalTrans’ specs. It’s a derivative of compost, but it has a lot higher nutrient base. Where TerraVita will be superior to compost is that it will keep feeding the soil.”
TerraVita HGM contains growth mediums; microbial growth stimulants; a small amount of wheat straw, thermally and mechanically processed to remove seeds and ensure consistent and even degradation; a tackifier; and a soil stabilizer.
“Organic Earth has worked hard with us for quite a while to get this to work with CalTrans,” Selby says. “When Kevin [Loucks] found out we were presenting CalTrans with a change order, he jumped on a plane from Colorado to help convince them.”
Selby and Loucks met with the CalTrans engineer on the project site. The engineer sent them to the CalTrans regional office in Stockton to talk to the landscape architect. They had the change order in one day.
Most of the project took place between February 12 and 18, 2014, which is late in the season for California. Ideally, seeding takes place at the beginning of winter, when there’s more chance of rains in the following months.
Selby’s is doing a trial run with CalTrans and documenting the results.
The soil was graded on the entire site. On one small plot, crews spread regular compost. On the majority of the site, they used TerraVita.
They used a second product by Organic Earth on three other test plots. Earth Essence is a hydraulic growth medium that contains mulch (HGM2), so it doesn’t require an erosion control mulch on top. They hydraulically applied Earth Essence Beta on one slightly sloped area, Delta on some of the steeper slopes, and Omega on the steepest, 1:1 slopes.
The seed mix was specified by CalTrans. “CalTrans has landscape architects who see what’s going on in the particular area,” Selby says. “Every mix is different for every project.”
Seed suppliers hand-collected the seed. They included Purshing’s lotus, lupins, California poppies, cattle spinach, dwarf goldfields, fescues, and pine bluegrass.
Selby’s used 31 pounds of seed, 1,425 pounds of 16-20-0 fertilizer, 1,500 pounds of fiber from Hamilton Manufacturing Inc.’s NaturesOwn Fibermulch, and an organic tackifier at 180 pounds per acre.
CalTrans will monitor the revegetation.
“It’s difficult to put timeframes on this kind of project because they’re so weather dependent,” Selby says. “Native seeds need at least four or five days of the soil being wet in order to establish germination, as well as sunlight and soil temperatures above 50 degrees. By mid-March, although there were only a couple of rains, I saw growth establishing. You have to allow nearly two years to establish mature vegetation of native seeds. Once the seeds germinate, these Organic Earth products will sustain the vegetation so it can continue to grow.”