Does Your Equipment Fit Your Work?
In the world of erosion control, there are any number of techniques for preventing erosion and keeping sediment in place. Think of hard armor, soft armor, silt fences, filter socks, and more retaining walls than you can shake a stick at, just to name a few. Every one of these has its own, specialized machinery, and you may not be aware of all the tools at your disposal. You may be using a hammer to do your work, when there’s a pneumatic drill that could do a better job.
While ignorance is bliss, it’s bad for business. With the tight labor market right now and, hopefully, more work to do this year, we’ll have trouble finding the people to fill our crews. If a piece of equipment can allow you to get more done with the same crew, it’s worth looking into.
The first step in considering any piece of equipment is to ask yourself if it fits with the work you do, or the work you’re planning to do. The erosion-control market has a variety of niches, and for many of these, there are machines that are tailored to be the best, most efficient option for getting the job done.
Take hydroseeding, for example. There are many hydroseeding clients, with many different properties, and there is no ‘one-size-fits-all’ hydroseeder. A 2,000-gallon machine that can shoot a stream of advanced mulch upwards of 150 feet may be great for large open jobs like highway revegetation, but it isn’t suitable for small, cramped residential properties. It’s a good hydroseeder, but it isn’t the right piece of equipment for reseeding a housing development.
There are a number of manufacturers of hydroseeding equipment that make various unit sizes. Hydroseeders are big-ticket items that can be customized in almost every aspect, so getting the right fit is important. At a glance, most would say that what differentiates one hydroseeder from another is the size of the tank. Admittedly, tank size is a major factor, but the agitation method—or how the ingredients are mixed—is also important.
Hydroseeders are either paddle-agitated, using blades to break up the mulch and mix it into the tank, or jet-agitated, using a high-pressure spray of water to do the same thing. “Jet-agitated machines will work fine with paper mulches, or wood/paper blends, even up to a 70/30 mix,” explained Ray Badger, president of Turbo Technologies Inc., in Beaver Falls, Pennsylvania. “But I don’t know of any jet machines that will handle more complex materials, like advanced mulches or 100% wood mulches.”
For years, hydroseeding mixes have been getting more complex, and the mulches used for hydroseeding have been getting heavier. There is still plenty of call for the lighter mulches that jet-agitated machines can mix, and if most of your contracts tend to call for paper or paper blends, you may want to stick with been towards paddle agitation for jet. However, the general trend has years now.
Getting back to size, a larger machine can likely spray farther and needs fewer tankloads to cover the big jobs, or jobs where the nearest same area as a smaller machine. On water source is a significant distance away, that’s a big help. But a large tank and a large machine isn’t always the right tool for the job.
A 2,500-gallon hydroseeder has a vance can quickly end up paying considerably higher purchase price, and much higher operating costs, than a 1,200- gallon machine. Those costs are constant, whether you’re using the bigger machine to its full potential or not. Erosioncontrol companies that buy a big hydroseeder with out lining up enough work for it in ad- dearly for their mistake.
One example of a large hydroseeding job is revegetating a badly- burned slope. Sean Casey is the president of the Finn Corporation in Fairfield, Ohio, and he recently headed out to recommend erosioncontrol measures in Gatlinburg, Tennessee, where a fire burned more than 17,000 acres of forest this past November. “It was primarily what’s called a ground fire, which means that the soil health may have been degraded,” he said.
Left to nature, forests are evolutionarily prepared for fire. Seeds buried deep in the soil sprout afterward and life quickly returns. However, if undergrowth is allowed to build up, it burns hot enough that the land is left barren, and the soil is exposed.
In these cases, the soil must be protected, or the next storm will cause massive erosion. The problem is particularly acute on steep hillsides. “In Gatlinburg, they have very steep slopes, 2:1 or 3:1 slopes, where it is just too difficult, and too dangerous, to reseed manually,” Casey said.
On a slope that steep, hydroseeding may be the only viable method of erosion control. With a big hydroseeder, you can mix tackifier, water, a mulch and native seed together, and shoot it 200 feet up the side of a hill, where it would be too difficult to roll an erosion-control blanket (ECB). Even if the root bed isn’t thick and deep before the next storm, a layer of grasses and the remaining tackifier will increase the soil cohesion and mitigate erosion.
Slopes that steep are rare, and in areas where runoff isn’t as dire a problem, some companies use mulch or bark blowers instead. “If the soil on a site is low in organic material, hydroseeding is more likely to fail, and you won’t get the proper revegetation,” said Larry Cumming, president of the Peterson Pacific Corporation in Eugene, Oregon. “With a blower truck, you can add compost mulch to the site that will include plenty of organic material to get the vegetation established.”
Mulch or bark blowers are mounted on trucks or trailers, and are capable of spreading a wide variety of materials more quickly than manual mulch spreading. “We estimate that one employee can manually distribute between one and one-and-a-half cubic yards of mulch per hour,” said Casey. Compared to that, mulch blowers can distribute six or eight cubic yards per hour, for the smaller units. The biggest machines can distribute one cubic yard per minute, with a two- or threeperson crew required to operate the machine.
Blowing mulch is also a more even distribution method than raking it. Instead of dumping out a pile of mulch and raking it around until it looks even, you’re blowing at a consistent rate. “A mulch blower uses 15 to 25 percent less material than manual spreading, for the same kind of job,” Casey said. “That’s pretty significant if you’re blowing thousands of yards of mulch per year.”
Mulch blowers also open up a very wide variety of work in some rapidly growing markets you may not already be in. For instance, the recent western drought has caused a major re-think about the amount of water we use in landscapes. This is causing more demand for drought-tolerant landscapes, which usually call for a lot of mulch. It is also incentivizing mulch blowing over hydroseeding, because a blower doesn’t require a tankful of water to use.
Depending on how rugged the machine is, you can blow fiber-based mulches, composted mulches, bark, soil, rock or even playground chips. The applications are simply too many to list. Some contractors even blow mulch to the tops of buildings for green roof installations.
Of course, that work is pretty rare, and there are much more common uses. “You can use a mulch blower to fill up a filter sock very quickly,” Cumming said. Filter socks are made of geosynthetic material and, when filled, form artificial berms that slow stormwater and capture sediment. They are usually used where heavy rains are expected and the resulting pressures would cause a silt fence to fail.
While we tend to think of erosion control in the context of sloped areas, because they need it the most, flat terrain is prone to erosion as well. The effects of wind and rain on flat or gently sloping ground may not be as severe, but they are there, and they do need to be addressed.
For these gentler applications, laying down straw is often the most cost-effective answer. Straw is cheap, and it tolerates the impact of raindrops without breaking up the way soil does. It provides a degree of protection from the wind, while also retaining moisture. Straw is not as strong as other erosion-control measures, but many jobs still call for it, and a straw blower is ideal for that work.
A straw blower takes compressed bales of hay and distributes them over a section of soil, ideally in a layer that is just thick enough so that the stalks will interlock. Interlocking strands will help keep each other in place, making the straw layer stronger than any individual stalk. To increase the straw’s ability to hold the soil, you can run over the newly-applied layer with a straw crimper.
A straw crimper pulls a series of parallel blades over the ground, tucking the straw into furrows in the soil, which greatly increases the straw’s resistance to wind. “You can drive by seeding jobs where they haven’t crimped the straw, and see where the wind has piled it up in some areas,” explained Aaron Burchland, president of Burchland Manufacturing in Gilman, Iowa.
All of the methods we’ve talked about so far are for blowing or spraying a material on the ground, but some jobs don’t call for either. Many projects specify some variety of erosion-control blanket (ECB) to be laid down and nailed into place. Happily, this process doesn’t have to be wholly manual, either.
There are attachments for carrying ECBs available for skid steer loaders or compact track loaders (CTLs). The skid steer may not travel much faster than a walking pace while carrying a 1,500-foot roll, but it’s one person driving, rather than three or four people pushing the roll.
Practically speaking, a two-person crew is usually assigned to installing ECBs, even with equipment. That way, one person can be stapling the blanket in place as soon as it hits the ground. The labor savings, however, are still substantial. After all, it is feasible for a skid steer to carry a much heavier, longer roll than a team could maneuver manually.
Erosion-control contractors often make use of CTLs and skid steers, and Gregg Zupancic, product marketing manager for John deere’s construction and forestry division in Moline, Illinois, explained why. “They are very wide machines with a lot of rubber under them, so they’re very stable and can work on steep grades,” he said. “Plus they’re transportable; you can move them from jobsite to jobsite without a commercial driver’s license.”
These handy machines also come with a mind-boggling array of attachments. Need to unload a bunch of heavy materials? Pallet forks are your friend. Need to carry backfill around the site? Hook up the multipurpose bucket. Need to compact the soil? You can get a vibratory roller in flat or sheep’s foot patterns.
There are also attachments that are specific to our work. “After the grading is done, and you have smooth, flat ground on a site, you can go over it with a power rake,” Zupancic said. “This will break up the soil to make a really nice seed bed, in preparation for hydroseeding.”
The most erosion-control specific attachment for skid steers and CTLs is, without a doubt, the silt fence installer. You can use a trencher to install silt fence, but having a dedicated attachment brings a few advantages.
First of all, it lays down the silt fence as you go. “It slices the ground, and puts the silt fence material in at the same time, so there’s very little soil disturbance, compared to trenching,” said Chris Mc- Cormick, owner of Silt Fence Plow in Pleasantville, Iowa. “Once it’s in the ground, then you just drive back along the edge of the fabric to compact the ground, put in your posts and tie it up.”
Instead of putting all that wear and tear on a trencher, you’re putting it on the cutting tip of a silt fence installer, a part that costs about $15. That’s the kind of advantage you can achieve by buying equipment that’s engineered to meet your needs. Equipment that’s specifically built for erosion-control work is more efficient than generic options.
This is only the start of the journey when it comes to considering what equipment to buy. Before you make any purchase, you should get down to the nuts and bolts, learn the technical details, estimate how much the equipment will cost you, versus how much more business you'll be able to do with it. Any purchase at this scale is a big investment, and should be weighed carefully.
Erosion control is a big enough field that an exhaustive list of equip-ment options would be difficult to read and impossible to publish. We've only covered a handful of them here, so if you find that there's a type of job out there that's eating up a lot of your time and manpower, do yourself a favor. Take a look online or call your equipment supplier, and see if anyone has a mechanical solution. You may find that there's a machine out there that's made just for you.