Start SMART: Determine the Best Erosion Control Product for Your Application

By Marc S. Theisen, Profile Products

Rolled blankets (ECBs) are best suited for sites that are easily accessible, have moderate-to-steep slopes and are prepared sites. They are also popular for small touchup jobs that do not justify the mobilization of hydroseeding equipment.

There are numerous erosion control product choices now available for landscape contractors. Choosing the right product for the particular project you?EUR??,,????'???re working on is a matter of examining budgets, site characteristics and matching the best applications. For years rolled erosion control blankets (ECBs) have been the norm for use on steep slopes and channels.

But today Flexible Growth Mediums?EUR??,,????'?? (FGMs?EUR??,,????'??), hydraulically applied, flexible erosion control blankets that form an intimate bond with the soil surface, are also increasing in popularity, thanks in part to on-going technological advancements. Which product is the best to use for your application? The following guideline is a simple rundown of the pros and cons for both products, which will help you select the right product based on your specific needs.

ECBs

Rolled ECBs are biodegradable and/or photodegradable products that protect slopes from wind and water erosion. ECBs are typically made of fibers such as straw, wood excelsior, coconut or polypropylene affixed to nettings. They are generally used on small projects and temporarily reduce soil erosion, while enhancing the germination and establishment of vegetation and come in several varieties that may last from less than 90 days to up to three years. In addition, they cover 80 to 85 percent of the ground and provide a moderate safety factor.

There are numerous ECBs available. When selecting one, it?EUR??,,????'???s important to consider three factors: (1) it will be used short or long-term; (2) what is the cost of installation and maintenance; and (3) will this product be successful when compared to other soil stabilizers.

Proven to be highly effective at minimizing soil loss and promoting seed germination, rolled erosion control blankets have many positive qualities. Traditional rolled blankets are manually placed onto bare soil, slopes and/or hills that have well prepared slopes with good access. Installation of blankets, which must be secured with trenches, check slots, stakes or staples, can be time and labor intensive. For a blanket to be completely effective, the site must also be prepared to minimize surface irregularities, which can cause a blanket to ?EUR??,,????'??bridge?EUR??,,????'?? the soil surface, leading to under blanket washouts and seed migration. They may also have a tendency to ?EUR??,,????'??tent?EUR??,,????'?? or lift from the soil surface when vegetation emerges. Once applied, the blankets provide immediate protection if the blanket is in intimate contact with the soil.

Through heavy and unseasonably abundant rains this spring and early summer, the coir blocks and blankets have held up well and the plants are becoming well established.

FGMs

FGM is hydraulically applied to steep slopes on a previously seeded surface with or without good access. It bonds directly to the soil, can be applied without direct access to the site and is effective without special soil preparation. FGMs are used on large projects and provide 99 percent ground cover and are the strongest, loftiest matrices available for erosion control and rapid vegetation establishment.

Like an ECB, once applied it is immediately effective against rain, capable of resisting and absorbing the full kinetic energy from raindrop impact and preventing dislodging of soil particles. Even though it is hydraulically applied, it forms the same flexible consistency of a blanket. FGM is composed of long strand, thermally processed wood fibers, crimped, interlocking man-made fibers and performance enhancing additives.

Because it conforms to the soil without site preparation, FGMs can offer better protection on uneven terrain and rough seed beds than rolled blankets, while providing the speed and cost savings of hydraulic seeding. To accommodate a broad range of conditions, FGMs can be applied at various rates and used along with other erosion control technologies. At lower application rates FGMs significantly and economically improve the vegetative establishment and erosion control performance of complementary technologies, from straw blankets to Turf Reinforcement Mats (TRMs). FGMs provide erosion control for less than a year, are 99 percent effective and provide a high safety factor.

Prior to construction, the stream bank profile was severely undercut and numerous places exhibited bank failure. The stream experiences periodic high water and overflow of banks in heavy rains.

The Bottom Line on Applications

Hydraulically applied blanket technology (FGM) is appropriate for small or large projects on prepared or unprepared sites. This includes projects with moderate to severe slopes, without access. Environmentally sensitive wetlands and other wildlife areas are a great application for FGMs.

These products are not suggested for use on heavy flow channels, for shoreline protection, or in areas where long-term protection is required by utilizing TRMs.

Both blanket products can be highly effective solutions to controlling erosion and establishing turf grass for new residential or commercial developments, roadside construction or golf course renovation.

FGMs

FGM is hydraulically applied to steep slopes on a previously seeded surface with or without good access. It bonds directly to the soil, can be applied without direct access to the site and is effective without special soil preparation. FGMs are used on large projects and provide 99 percent ground cover and are the strongest, loftiest matrices available for erosion control and rapid vegetation establishment.

Like an ECB, once applied it is immediately effective against rain, capable of resisting and absorbing the full kinetic energy from raindrop impact and preventing dislodging of soil particles. Even though it is hydraulically applied, it forms the same flexible consistency of a blanket. FGM is composed of long strand, thermally processed wood fibers, crimped, interlocking man-made fibers and performance enhancing additives.

Because it conforms to the soil without site preparation, FGMs can offer better protection on uneven terrain and rough seed beds than rolled blankets, while providing the speed and cost savings of hydraulic seeding. To accommodate a broad range of conditions, FGMs can be applied at various rates and used along with other erosion control technologies. At lower application rates FGMs significantly and economically improve the vegetative establishment and erosion control performance of complementary technologies, from straw blankets to Turf Reinforcement Mats (TRMs). FGMs provide erosion control for less than a year, are 99 percent effective and provide a high safety factor.