When Chesapeake Energy needed hydroseeding work done for a gas pad area in Wetzel County, WV, the energy company called in Central Carolina Seeding, based in Winston-Salem, NC.
“It was a slip repair,” says Central Carolina Seeding’s president, Sam Howard. “They had had a massive landslide, and we helped with the repair.”
The hydroseeding portion of the repair project took place from September 2 to September 15, 2012. The work covered about 15 acres of land that was essentially a deep ravine.
“It was 1,700 feet from the top access point down to the bottom of the ravine,” Howard recalls. “Some parts were almost vertical.”
After the ground was seeded, Profile’s Flexterra High Performance-Flexible Growth Medium, a spray-on blanket of bonded fiber matrix, was applied over the entire site. Then 8,000 feet of wattles were laid to slow water runoff.
Howard says the work has held up well. “Three days afterward, the site had over 4 inches of rain, and it was fine.”
The seed used was from Pennington Seed Co. of Charlestown, WV. Pennington’s Slopemaster is a seed mix specifically designed for erosion control, where there is a need for grass to be established quickly and there will be little or no follow-up maintenance. The Slopemaster seed mixture includes Durana, a variety of durable white clover. This medium-leafed, intermediate type of white clover contains as many as 97 stolons per square foot, enough to secure most erodable soils.
In a year’s time, Durana will put up to 150 pounds of atmospheric nitrogen into the soil per acre, helping whatever type of grass is seeded to thrive. Slopemaster is also treated with Pennington’s GermMax technology for enhanced establishment. “They tweaked the seed mix with some Black Walnut seed, hoping that some trees would grow there,” Howard says.
To give the new seeds a boost, starter fertilizer of 10-20-20 was added. So were Profile’s JumpStart and Aqua-pHix soil amendments. Aqua-pHix was applied to lower the pH level of the soil. JumpStart is a liquid blend of a soil penetration agent, humic acid, and over 200 species of beneficial soil bacteria. It helps the soil retain moisture so that revegetation occurs more quickly.
“We were not left with the best material to grow grass on,” Howard observes.
He notes that the biggest challenge of the job was “the access, getting to the bottom of the ravine. There were some roads the bulldozer could travel on, but they were not good enough for a truck.”
To accomplish the task, Central Carolina Seeding crewmembers first mounted their hydroseeding machine on a truck, then hooked the truck to a bulldozer. They had 700 feet of hose to spray out the seed mixture.
“We took the hydroseeding machine more than halfway down, then the hose came out. It took us an hour to get the hydroseeding machine down and up. We had to do that several times,” Howard explains.
The crewmembers used a C330 paddle-agitating hydroseeding and hydromulching machine from Epic Manufacturing in Greenwood, DE. It features a load-sensing, pressure-compensating hydraulic system. Howard notes that the crewmembers really like to use this machine.
Another challenge related to timing. “There is a creek at the bottom of the ravine. Because of the landslide, the stream had to be repaired by another company. We worked around their work,” Howard says.
In addition to the size and severity of the site and working around the stream repair project, the hydroseeding crew knew “the material had to be applied in such a short time. We had to get in and get it done as quickly as possible,” Howard notes.
He adds, “We had a short window because mid-September in West Virginia didn’t leave much time for getting the grass established and growing before winter cold set in.”
Weather, which often makes hydroseeding work more difficult and results less than desirable, was not only cooperative, but actually in Central Carolina Seeding’s favor on this job. “It couldn’t have been better,” Howard says. “We had sunny days for the installing and then a 4-inch rain within two to three days, then steady rain through the fall that gave us good results.”
He concludes, “I was surprised at how great the results turned out. It was very challenging work.”
Bypassing Mt. Pleasant
“It’s an 80 million dollar project. Our contract is a little over $3 million. We’re doing all the seeding and erosion control work on it,” says Danny Marsh, president of Southwest Environment Services in Tyler, TX.
Marsh is referring to his company’s hydroseeding work on a large highway bypass project that would take traffic-especially trucks-around Mt. Pleasant, TX, instead of through it. The spot is where US 271 ties into I-30 in Titus County, TX.
“We’re shooting now and we’ll work the rest of this year [2013], and we worked all last year on it,” Marsh says. “We have a crew that stays up there and works on that project every day.”
The design-build project is managed by PTP Transportation of The Woodlands, TX. The contractor is Williams Brothers of Houston, one of the largest highway construction firms in the US.
Southwest Environment Services is responsible for applying a total of 2.8 million square yards of bonded fiber matrix. Of this amount, 1,427,503 square yards are of permanent bonded fiber matrix. Another 990,488 square yards are temporary warm bonded fiber matrix. The remaining 424,496 square yards are temporary cool bonded fiber matrix.
Marsh says block sodding for the project totals 35,621 square yards. “We have close to 1,600 cubic yards of riprap, wire fence, and silt fence, but no gabions on this project,” he adds.
The area with permanent seeding is about 295 acres, all bonded fiber matrix. The site features all new construction on the location of former pastureland.
Marsh says that when using bonded fiber matrix, the company does not have to add tackifier or mulch. He notes that the project has “some pretty good slopes, header banks like the on ramps and railroad tracks, and several bridges.”
The seed mixture for the permanent seeding on the project includes five types of grass: green sprangletop, sand love grass, whole Bermuda, German foxtail millet, and weeping love grass. Green sprangletop is a nursery grass that germinates quickly to provide cover.
No wildflower seeds are included. The temporary warm and temporary cool areas have different seed mixtures.
Marsh notes that the project site has very sandy soil. “The pH is very low, so we put in high-count pelletized lime and organic fertilizer.” To get the seeds and other materials applied properly, Southwest Environment is using an Epic 330 hydroseeding machine with a tank capacity of 3,000 gallons.
No wattles are being used. Since the area has a lot of creeks and therefore water runoff, riprap will be used in many of the ditches.
Marsh says the creeks present challenges for his crewmembers. “Soil so sandy is the main challenge. Every time they get things ready we have to shoot right then to keep erosion controlled.”
Weather has also presented difficulties. “Last year this particular project had some big rain events. In January, February, March, and April of 2012, we had a tremendous amount of rain,” Marsh recalls. “This year, for quite a few days we’ve had rain, but not the big events [like last year]. Rain definitely has been a factor. Now that we’re planting grass, we want it. It’s nice to have the rain now.”
Marsh says the bypass project “is one of the largest projects of this kind to use bonded fiber matrix. We’ve been doing this type of work since 1992, and this is the only project where we used bonded fiber matrix for all temporary and permanent seeding.”
At Southwest Environment, he adds, “Normally we use hay mulch or hydromulch or blankets, or a combination of the three of them.”
Why the different materials on this project? “The design engineers specified the bonded fiber matrix because of all the sand. It’s difficult to use blankets in temporary settings, and also there’s been so much runoff water with the rains,” Marsh explains.
The Texas Department of Transportation, PTP Transportation, Williams Brothers, and other partners in the project meet weekly to discuss problems and progress.
“Everyone is pleased with the way things are going,” Marsh notes.
Building an Island
Jeff Pezzetti, president of Pezzetti Erosion Control in West Des Moines, IA, and his hydroseeding crew completed an unusual project just east of Des Moines in July 2013. They prepped and sprayed the area in one day.
“We built a small island on a pond on private property,” Pezzetti says. “It was a landbridge surrounded by a recreational area. The property owners wanted to have a way to walk out and fish off of the island. They wanted grass that would stay less than knee high.”
Pezzetti and his crew hydroseeded a special fescue blend mixed in with a 70/30 wood/paper hydromulch. The area covered was about 35,000 square feet, or three-fourths of an acre.
For a tackifier, the crew added Finn’s E-Tack to the mix. This polymer material binds soil and mulch electrochemically.
As is often the case with hydroseeding work, the biggest challenge of the project was gaining access to the site. In this case, the worksite was 40 to 50 yards off of the road.
“We had to hook the hydroseeding machine to a dozer and pull it. The ground was too soft to drive a truck that close. A truck-mounted machine would never have gotten there,” explained Pezzetti, whose crew used a Finn T120 HydroSeeder.
“That’s one of the reasons I bought the machine,” Pezzetti says. “It’s more versatile. It has steel rings that allow it to be pulled with other pieces of equipment besides a truck. It’s the smallest of the biggest machines: It’s big enough to do big jobs, but small enough for special jobs with limited or no access.”
He adds, “We’ve done a lot of that type of work, for railroads and others. Ponds in particular have little access.”
As a past example, Pezzetti recalled using the Finn T120 on a job where “we picked it up with an excavator-a crane-and set it down inside of a courtyard. When we finished, we pulled it back up and [over the building] with the crane.”
As for the weather while the island project was ongoing, Pezzetti notes, “It was a beautiful day. The ground was dry but still soft, which made it more challenging to get to the site.”
The grass should be growing well by mid-August, thanks to its mulch cover. Pezzetti says he cautioned the property’s owners that it was late in the season to be putting out grass seed, “but they’ll take their chances.” With a little luck and help from Mother Nature, the Iowa pond’s owners and their friends will have a convenient and attractive path to catching some bass or catfish.
To negotiate the rough terrain of Wetzel County, WV, Central Carolina Seeding crewmembers mounted their hydroseeding machine on a truck, then hooked the truck to a bulldozer.
Saving the Bluffs
For the last several years, Rob McGann, president of Hydro-Plant in San Marcos, CA, has had his hydroseeding crews working on beach bluff revegetation jobs. “We probably do two a year, on average,” McGann says, noting that getting access is the most challenging part of the work.
Hydro-Plant is doing the reseeding for homeowners’ beach bluff lots overlooking the Pacific Ocean in San Diego County. The residential lots range in size from one-tenth to one-half acre.
The hydroseeding follows construction of seawalls to stop erosion, which is a serious problem given the winds and water. Homes were built close to the edge of the bluffs, for the magnificent views. That practice has added to the instability of the land.
Another factor causing the high degree of erosion is the shallowness of the soil. Some of the seawalls are built on native sandstone.
“It’s kind of a gamble to shoot seeds there and hope they’ll find pockets of soil to grow in,” McGann says.
Installing seawalls and hydroseeding the bluffs for revegetation fall within the guidelines of the California Coastal Commission. This regulatory agency functions on a regional basis. The commission has broad powers to protect the sensitive coastal environment. It regulates what private property owners must do on their land that adjoins the beaches.
In areas where the beaches below are open for visitors, these hydroseeding jobs on bluff lots frequently draw the attention of beachgoers. They crane their necks to watch the hydroseeding crew at work with their hoses dangling from the hydroseeding equipment at the buff’s edge.
“The guys have to belay down the slopes on ropes,” McGann says. “Other times the contractors [for the seawalls] provide a cherrypicker for us to use.”
The slopes are sheer drop-offs, though sometimes there are little walkways or ledges that the crewmembers can use. “It’s 1-to-1 most of the time,” McGann says.
Seeds for the beach bluff revegetation came from S&S Seeds of Carpinteria, CA. They were all for native wildflowers and shrubs. “We used two dozen coastal indigenous species, from Beach Evening Primrose to buckwheat, the more common type,” McGann says. “We also included Sea Dahlia, which is unique to San Diego County.”
For the hydroseeding mixture, “We used a heavier rate of application-3,000 pounds per acre instead of the usual rate of 2,000 pounds,” he notes. He explains that the heavier application was necessary because of the very loose soil-lots of decomposed sandstone. “Plus, we have wind and water erosion issues,” he adds.
The slurry contained guar gum binder as a tackifier and a humate product for fertilizer. Germination enhancer and soil activator were also added.
Revegetation here depends on rainfall for hydration. The Coastal Commission prohibits homeowners from installing irrigation systems. They can water with hoses, but water rates are high, and getting the water to reach the plants often isn’t possible.
This type of hydroseeding work is typically done in the fall, anticipating the first seasonal rains of November and December. The heaviest rains fall in January and February, sometimes in March.
The jobs typically take one day or less to accomplish. “One in the north of the county took us three days,” McGann recalls. “We had straight westerly winds [that would have blown the hydroseeding material away] that we had to wait out.”
McGann says homeowners on these beach bluff properties are happy to see the hydroseeding crew arrive because they know it’s the last part of work that has to be done so they are in compliance with the Coastal Commission.
Hydro-Plant’s seed supplier, S&S Seeds, specializes in native seeds and native seed blends. Victor and Susan Schaff, who founded S&S in 1975, say climate changes have affected the business. “The two-year drought in California has refocused the need to use more native drought-tolerant plant seeds,” Victor says.
Warmer temperatures have also changed the way that S&S Seeds grows seeds for sale to hydroseeding companies, plant nurseries, and other firms that rely on the company for high-quality native seeds in both standard and custom mixes.
“We have had to increase irrigation at our farm during the winter months, which typically were our wettest months,” Schaff notes. This irrigation has, of course, added to the company’s operating expenses.
When asked about trends of recent years in the commercial seed business, Schaff says, “There has been a tremendous increase in seed usage to revegetate soils disturbed by solar site installations. They are primarily using native seeds with local origins.”
S&S Seeds is a primary wholesale supplier to landscape contractors, government agencies, and seed distributors throughout the United States and abroad. The company keeps more than 450 acres in seed production and also does wildland collection of seeds. That amount of access to seeds means that customers can choose from more than 1,000 species of native grasses, wildflowers, and shrubs. They can order stock seed mixes or request custom seed mixes for commercial and residential projects.
S&S Seeds will even contract to collect seed from specific sites for a project. The seeds so collected are identified, cleaned, tested, and stored properly. S&S employees can locate stands of harvestable plants within the project’s defined zones. This stand assessment helps ascertain potential yield of the plant’s seeds, harvest date, and the size of collection crew required to meet a job’s deadlines.
S&S Seeds maintains a state-of-the-art seed cleaning facility where harvested field material, after proper drying, is taken. The dry, conditioned seed is assigned a unique lot number and stored in the company’s warehouse facility. Special long-term storage arrangements can be made if needed. If desired, samples are sent to an independent certified seed-testing laboratory for purity and germination tests. Specific reports as required by the project can be provided.
The company’s acres are used not only to grow seeds for customers and obtain a ready supply of seeds needed for specific ecoregions, but also for research and trial fields. Both new and old species can be easily compared for productivity, disease resistance, and other characteristics.
These four companies, in Texas, North Carolina, Iowa, and California show the diversity of hydroseeding work. The details of their projects also show how important it is to choose the appropriate seeds and supplemental hydroseeding materials for the types of soil and microclimate.
Meeting the challenges of slopes and soils, too much or too little rain, and temperature and wind fluctuations isn’t easy, even for a seasoned hydroseeding professional. That’s why successful projects such as these four are both instructive and interesting.
