Essential for successful onsite soil stabilization for practically any circumstances, vegetation management commonly involves three types of approaches:
- Physical (mowing, brush clearing)
- Chemical (the use of herbicides or chemicals to kills weeds or non-native species before replanting with desirable species or to inhibit the growth of certain plants)
- Biological (releasing insects to kills certain types of plants or using herds of grazing animals to do the “mowing'”)
Zanga Schutte’s Z-Bar Ranch in Kamuela, HI, uses all three methods. Z-Bar Ranch is a cow/calf operation that runs 1,000 cows on 3,500 acres.
Schutte has used Diamond Mowers’s Ecoblade, which relies on WetBlade technology. Essentially, herbicide is applied directly to the blade. As the blade makes contact with the vegetation, herbicide is wiped onto the cut surface. The herbicide is absorbed into the root system of the vegetation and is not prone to wind drift or ground soak.
Schutte praises the system for helping him better manage ranch operations. “It cuts whatever brush you’re trying to eradicate and applies herbicide right to it, so now I have instant pasture,” he says. “I call it instant gratification. I believe this is the answer to getting rid of any kind of brush or noxious weeds you want to get rid of. You’re clearing the land, killing any brush or weeds that are out there, and so you’re conserving the land and doing a better job by maintaining and managing it.”
Schutte uses the system to rid ranch land of invasive strawberry guava plants and fireweed. “The fireweed has taken over a lot of our pastures. That has to do with poor management as well as the terrible drought we’ve been in for several years,” says Schutte. “I’ve used the WetBlade to do a few demos with the fireweed, and it is incredible. I can get rid of that fireweed, which is a nitrogen-driving product that takes over the forage. There’s really good recovery on the pasture after using WetBlade.”
Schutte was able to purchase the Ecoblade through a grant with the help of the Natural Resources Conservation Services and farm service agencies. “It’s helped us to stay in business and afford to be able to run the machine for the noxious weeds and brush we’re trying to eradicate,” he says. “The grants are available for small business guys to be able to deliver more with our ranches and try making them better. We’ve had some difficult times, especially with the way the weather has been.”
Schutte connected with Diamond Mowers when the manufacturer did a weeklong demonstration project on the island of Hilo in June 2009 at the invitation of an agronomist attempting to manage weeds. It’s become a particular problem in Hawaii, exemplified by one 4,000-square-mile location that’s being overrun with a tall nuisance plant that migrated from Japan.
During Diamond Mowers’ visit, test plots were set up demonstrating an area with a standard cut, a cut with water applied, and a cut with herbicide.
“The idea was to see what kind of results we were going to have with this application,” says Dave Burkhart of Diamond Mowers.
Ecoblade can be used on any type of rotary mower. The chemical is brought down through a dish with small holes through which it is dispersed onto the blade. The centrifugal force of the rotary blades enables the plant to pull the chemical down and off the blade.
This system replaces earlier technology in which the chemical went from a storage tank through the spindle housing, then through the dish and to the blades, so when something broke down, the full spindle would have to be replaced.
Working Around Water
Meanwhile, in Georgia, Estate Management Services of Brunswick, GA, is using SePro aquatics herbicides for its weed control services in aquatic environments and construction.
The company services the residential, municipal, and commercial sectors with a fleet of airboats, harvesters, tractors, land rigs, and smaller boats. Much of the company’s work is performed on right-of-way areas with ditches that function primarily for drainage.
Estate Management Services’s clients seek to have vegetation management that controls stormwater flow. Many projects involve rights of way for utilities and are supervised by a stormwater manager.
“Occasionally, on commercial properties, they will have a ditch or area that runs through the middle of the commercial facility where they want it to look ornate, and they will do shoreline vegetation planting that will give it color and texture instead of a single texture or cattails that are generally more obstructive to flow,” says Estate Management Services owner John Crabb.
Clients are now seeking creative ways of revegetating to keep stormwater flowing without it the contaminants it can carry along with it.
“The city of Savannah is trying to figure out a way to use different plant materials that would remove the impurities but not impede the flow,” Crabb says.
He says a typical project for his company is exemplified by a recent job in South Carolina. “We had a project where there was an easement on either side of a canal. The canal was OK, but the drainage was a problem,” he says. “There were pretty steep slopes on this canal. They wanted to improve the drainage off the canal as well as away from the canal and asked us to remove all of the vegetation by herbicide.”
Estate Management Services treated about 33 linear miles with an application of SePro’s Habitat and Aquapro to broaden the range but still achieve long-term control. “Four to six weeks later, we got the results,” notes Crabb.
Crabb sometimes encounters objections to using herbicides. “A lot of folks aren’t as familiar with herbicide, and you encounter some resistance to it, particularly if it’s close to drinking water. Even though our labels clearly define it as being OK for us to apply certain chemicals in or close to drinking water, there’s a lot of hesitancy. I’ve run into a lot of glitches where I’m trying to get something approved, and, just because they’re not too familiar with it, they will not approve it.”
Crabb will then bring in a chemical company representative, a state agricultural agent, or someone from the water management district to verify that he is licensed and the chemical is labeled for the intended application.
He has seen clients excavate their ditches, such as one who used two tractors with heavy anchor chains, dragging them along the ditch to get rid of the weeds because they weren’t comfortable with herbicide application.
“That was based solely on not having a good understanding of what those chemicals are used for,” he says. “Generally, to treat with herbicides and maintain the vegetation so that your flow rate continues is considerably less expensive than it would be to dig it out every year because of the equipment, the man hours, and the disposal.” The only time excavation is needed is for removing silt from drainage channels, rather than for vegetation management. “The newer herbicides have a much longer control time and a much broader range,” notes Crabb.
Vegetation maintenance is typically funded by a municipality for utility right-of-way work. But there can be funding issues when multiple riparian areas and easements are involved, in which case the owners sometimes assume some of the costs, Crabb says.
Because vegetation management often involves access issues, Estate Management Services is uniquely positioned to address that through its variety of equipment. “An example is a long drainage ditch that’s particularly wide and runs through a heavily wooded area where there may not be adequate area on either side to get a tractor through,” he notes. Estate Management Services can do the job using an airboat instead of a tractor, which is normally how it’s done, Crabb points out.
Airboats and other equipment can be noisy, and Crabb’s company must comply with noise ordinances specified by the contractor. “It’s generally a neighborhood they’re most concerned with,” Crabb says. “Most of the time, 8 a.m. to 4 p.m. is the standard time to operate.”
Exceptions sometimes occur if there is a great deal of work to be done in a certain area or if the company is working with a chemical that favors a lower pH condition and Crabb believes he can get better control by doing the work at sunrise.
SePro offers a variety of aquatics herbicides, including Clearcast, which controls floating, emerged, and shoreline weed species while allowing desirable plants to colonize. It is the only herbicide on the market that has been granted a tolerance exemption by the USEPA. As such, there are no food residue limits for Clearcast in fish, shellfish, crustaceans, or irrigated crops. Another herbicide, AquaPro, is a glyphosate-based herbicide used for nonselective broad-spectrum control of weeds, brush, cattail, and other emergent plant problems. It is formulated for use around aquatic environments without harming fish. Habitat is an herbicide used in areas where there are no desirable trees or vegetation, and Renovate Max G is an aquatic herbicide for selective and systemic control of broadleaf aquatic weeds.
“Clearcast and Habitat are both systemic herbicides, which means you get better root control of the target vegetation,” says Todd Horton, a former BASF employee who now serves as the aquatics development manager for SePro. BASF sold its aquatics division to SePro.
“You don’t have to come back and respray,” Horton adds. “Anytime you’re doing work on rights of way and easements, the one thing that all of them want-whether it is a county or department of transportation- is to reduce the amount of time they have to be out there, for safety. So when you go and do an application, you don’t want to have to return anytime soon.”
Choosing the Right Seed
Some companies take an approach that doesn’t involve the use of chemicals or herbicides. Chuck Joswiak of WindScapes in Inver Grove Heights, MN, says his company uses a lot of yardwaste and compost from Resource Recovery Technologies in Minneapolis in its line of work.
The company offers a variety of services to a broad range of sectors, including municipal, department of transportation, residential, and commercial.
Services include mulch applications, landscaping, playground work, terraseeding, soil work, erosion control, and stormwater management. WindScapes also uses products from Filtrexx International. Additionally, through the use of Express Blower trucks, the company is able to obtain work in difficult-to-access sites.
In many cases, WindScapes helps establish vegetation and then educates the owner or end user on maintaining it.
Joswiak says site-specific conditions drive the choices of certain types of vegetation.
“The Minnesota Department of Transportation has a list of different seed mixes they prefer,” he says. “Those are designed based on different areas in the state of Minnesota, because we have different climates throughout the state and we also have a lot of different soil types throughout the state.”
Another part of the decision-making process is whether DOT officials want the area maintained on a regular basis or want to let it grow naturally.
“A lot of that comes down to the person designing the project in the first place,” notes Joswiak. “We don’t make the final call, but we do make a lot of recommendations. There are architects working on projects-not necessarily DOT, but commercial and industrial sites-and they will pull a random selection out of the DOT mixes, but we will work to educate them on what it is going to entail over the years to come and what their best options are.”
Sometimes, that means adjusting the seed mixes accordingly, because the project owner may not have had a good understanding as to what the end result would be.
In helping clients to eliminate the use of pesticides and herbicides, WindScapes has been educating them on amending soil. “You can get a healthier plant, and in the long-term, a healthier plant needs fewer chemicals. A plant will survive better than some of the weeds that are out there if you can get it healthy enough,” says Joswiak. “That can help eliminate the use of pesticides and herbicides.”
More locations are also being maintained as stormwater management sites, Joswiak notes.
“We’re seeing a lot of municipalities reworking their infrastructure to accommodate runoff,” he says. “They are using any type of infiltration system to collect road runoff. By using different compost materials, we can increase the filtration properties of the soil. Rain barrels have also become very popular in Minnesota. It all comes together.”
Teaching the Basics
Proper vegetation establishment that leads to effective vegetation management has become front and center of the classes that J.W. Lemons, an International Erosion Control Association (IECA) member, teaches.
He also provides consultation for his sons Deric and Devin, whose hydroseeding and erosion control company, Earth Control, serves Texas and Oklahoma. Lemons is also a general manager of SECA, the Stormwater Environmental Compliance Alliance, and teaches classes on compliance, primarily in Texas and Oklahoma.
“We started teaching classes to each one of our cities,” he says. “We did what we call a Stormwater 101 so that our customers-builders, developers, contractors, engineering firms, and the cities we were working in-were all on the same page.”
Lemons now teaches inspectors, architects, and others involved in stormwater issues, with a student count now surpassing 2,000.
In his travels throughout the United States, he’s noted that government and commercial agencies appear to have difficulties knowing how to properly establish vegetation.
“The soils have been disturbed, including all of Mother Nature’s efforts at making any kind of topsoil where you have microbial activity or natural nutrition from decaying plants,” he says. “They take an almost sterile situation with subsoil and a lot of rock and throw seed at it.”
Lemons cites an example that he calls common but disconcerting. En route to Houston with his business partner, he noticed a small pickup truck driving down a disturbed area between two four-lane highways with a large tub of seed in the back.
Workers on either side of the truck were lifting their hands up into the air and throwing seed up from the pickup, which was moving very fast so the wind would broadcast the seed, says Lemons.
“Now, that was a very effective and very efficient way to use taxpayer money,” he notes sarcastically. “What was so comical is that we didn’t spot them at first. What we spotted was the flocks of birds that were following them. It was like, “˜Come and get it!'”
From that experience, Lemons decided he was going to teach effective vegetation establishment in his classes.
“Even in temporary situations, there are a number of large developments where they shave off all of the soil and stockpile it. The stockpile may sit there for 14 days or 14 months. If it’s going to sit there for a while and be a pollutant hazard for erosion control, what’s wrong with broadcasting a little bit of seed on it and getting some vegetation to hold the soil up? Draping some erosion control blankets over it? Then if they don’t need the topsoil for the next three years, so be it. They can come back in with their giant loaders, stir it back up, and put it on the ground and use it later on.”
Lemons says his primary vegetation management concerns center on establishing vegetation in construction situations.
“Typically, construction does more damage to the soil base than it’ll ever do good, and that’s because of grading,” he explains. “We take the topsoil off, and in many cases we try to save it by putting it off to the side, but in the meantime we’ve got all of this grading on huge amounts of acreage that has disturbed the soil.
“There”˜s no vegetative cover for as much as three or four years, which is not acceptable to be in compliance with the Clean Water Act.”
Detention ponds are also more effective with a vegetative cover, Lemons says.
“Geotextiles play a huge role in that,” he adds. “You want structural integrity, but you still want drainage so you don’t flood out your vegetation and it can maintain and hold water for a temporary period of time.”
Lemons emphasizes proper vegetation establishment in his classes for engineers and architects because “here’s one of Mother Nature’s easiest fixes, if you just put a little bit of time, effort, and money in it,” he says. “It is a lot more cost-effective to get vegetation back, even if it’s temporary, than it is to install all the physical erosion control items that we have out there. Those have to be maintained and replaced when they’re damaged, but vegetation’s pretty forgiving.”
Once vegetation is established, maintenance involves “keeping it to a dull roar,” notes Lemons. “You don’t let it get too tall so it becomes a different kind of hazard, like a fire hazard.”
Economics is what drives the choices for the sites, although the approach of saving a buck now may mean spending far more down the road.
For example, he notes, government entities usually have established guidelines as far as what seed should be used. “Somebody calls a company and they’ll put it on, but they may be putting it wrong because they’re doing it the fastest and easiest way they know how to do it; that might be throwing the seed in the air from a pickup truck,” says Lemons.
“So it doesn’t establish, and then we get those really wet rains like we did this year, and get landslides because the vegetation wasn’t established right.”
Choosing a knowledgeable erosion control specialist helps to avoid such problems, Lemons points out. “If they had recruited the right kind of people, who have a background in agriculture, agronomy, or horticulture, they would have known they were doing the wrong thing on some of those slopes,” he says. “Now they’ve realized after the fact, and after it has cost the taxpayers hundreds and thousands of dollars, that maybe that wasn’t the best way to do it.”
Lemons will sometimes ask those who take his class to raise their hands if they’ve taken any previous soil or plant classes. Usually, he says, the response is minimal. “These are the people who are specifying what needs to be put on the ground, and yet they’ve never had these classes,” he points out.
Improper vegetation establishment and maintenance of any site often can mean the site runs afoul of regulations.
“We’re setting up all of these things to protect our water system and keep pollutants out of it,” Lemons says. “You can establish the vegetation but fail to maintain it right. Let’s say the site needs 50 pounds of fertilizer and Joe takes 150 and puts it on there just because he has it. One hundred pounds of that is leaching off and getting into our water system, doing more damage than leaving the soil bare and having the soil go in.”
Once newly established vegetation is stable, maintenance is usually turned over to a homeowners association or property management group, but, Lemons says, there can sometimes be a difference of opinion on what constitutes “stability.”
“According to the EPA, it’s 70% vegetated cover of the native vegetation that existed there prior to disturbance,” he says. “If I’m out in the desert and I’ve got five cacti and a couple of sage brush, then I only need to establish 70% of what was there; I don’t need to have a green lawn growing.”
That is often misunderstood in the regulatory world, Lemons says. Regulators may complain that the site isn’t “70% covered” when it never was in the first place.
“In the construction industry, we have our landscape plans, and we hand them off to someone; what are their qualifications?” Lemons says. “They’ve got trees, shrubs, lawns, and bushes they want to grow, and then the landowner is stuck with trying to make that stuff grow in a situation where it may just not work.”
Just as important as plant choices are the supplies that will help good vegetation thrive and minimize nuisance vegetation. The use of landscape and drainage fabrics helps control weeds and unwanted vegetation, enabling shrubs or flowers to grow in dedicated landscape areas and allowing for easier maintenance, Lemons points out.
Lemons uses products from L&M Supply for vegetation establishment, including geotextiles, erosion control products, silt fence, and landscaping material. “They cover it from A to Z,” says Lemons. “I’ve got such a wide parameter of blankets for every situation, from the single-net straw blanket that can be put on a fairly mild area all the way to heavy-duty coconut fiber on a steeper slope that needs to stay up there longer and needs to have a better UV resistance, better runoff, and weather resistance. Coconut can be used on even steeper banks and can also be used on banks where there are going to be high-velocity flows.”
