Ernst Seeds Bioengineering Materials

Soil bioengineering is the term used to describe the use of plant material to arrest and prevent slope and streambank failure and erosion. The roots and stems serve as structural and mechanical elements in a slope protection system. Live cuttings and rooted plants are embedded in the ground in various arrays to serve as soil reinforcements, hydraulic drains and barriers to earth movement. Once established, this living material effectively controls a number of stabilization and erosion control problems by binding the soil with its root system and creating a natural vegetative cover. Bioengineered sites are self-repairing and have the advantage of blending with natural surroundings.

You can find a Bioengineering Materials Guide and a Bioengineering (Shrub & Tree Materials) Price list by visiting our Download Center.

Ernst Conservation Seeds is an experienced producer of common and specialized live soil bioengineering materials. We understand the unique needs of bioengineering site construction. Our material is grown, processed and delivered to minimize on-site installation labor and maximize survival and quick establishment.

LIVE STAKES

Live stakes are dormant, live woody cuttings of a species with the branches trimmed off. Live staking performs an important function in creating a root mat that stabilizes the soil by reinforcing and binding soil particles together. Stake establishment also improves aesthetics and provides a habitat for wildlife. Live stakes can be used on their own to secure other bioengineering materials or as an anchor for erosion control and geofabric. Stakes or poles can also be inserted or driven through openings in rock structures, such as gabions, riprap and other retaining structures.

INSTALLATION NOTES

Install stakes during their dormancy (late fall to early spring). Do not allow them to dry out. Soaking before planting significantly increases survival and growth rate. Drive a pilot hole in firm soil, planting at right angles (buds oriented up) with at least two-thirds of its length underground. Plant stakes randomly or 3’-6’ apart on triangular spacing. Tamp the soil down around the cuttings and water. If a long dry spell or hot weather is expected after planting, irrigation may be warranted.

Salix lucida (Shining Willow)
Salix nigra (Black Willow)
Salix purpurea (Streamco Willow)
Salix sericea (Silky Willow)
Salix x cottetii (‘Bankers’ Dwarf Willow)
Sambucus canadensis (Elderberry)
Viburnum dentatum (Arrowwood)
Viburnum lentago (Nannyberry)

BRUSH (BRANCH) LAYERS

Brush (branch) layers are living branches placed on a terrace along contours of a streambank and interspersed between layers of soil. This technique is used to repair a slump or gully and is most effective for revegetating scour holes.

INSTALLATION NOTES

Brush (branch) layers are placed on terraced benches with two-thirds of the basal material tilted into the slope and covered with soil. Branches should protrude beyond the face of the terrace. Before installing, soil terraces can be additionally protected by putting down geofabric. Starting at the bottom of the slope, secondary brush (branch) layers can be added every 3’-4’ proceeding up the slope. Straw mulching the finished surface is recommended to provide moisture retention and additional erosion control. Planting should be done during the dormant season.

Salix lucida (Shining Willow)
Salix nigra (Black Willow)
Salix purpurea (Streamco Willow)
Salix sericea (Silky Willow)
Salix x cottetii (‘Bankers’ Dwarf Willow)
Sambucus canadensis (Elderberry)
Viburnum dentatum (Arrowwood)
Viburnum lentago (Nannyberry)

BRUSH MATTRESSES

Brush mattresses are layers of living branches laid in a crisscross pattern, 1-2 branches thick, on a streambank to form a living ground cover. The mattress that is formed protects the bank surface until the branches can root and native vegetation becomes established. This living system normally roots in the entire bank face, encouraging natural infiltration and immediately acting as a sediment trap.

INSTALLATION NOTES

Place material with the basal ends located toward the bottom of the slope. Using 3’ square spacing, drive dead wedge stakes into the plant material. Stretch wire or biodegradable twine or rope diagonally around the dead stakes and finish driving the stakes in to tighten the wire, twine or rope and secure the mattress. Finally, place a thin layer of soil over the entire area to encourage rooting. Irrigation is necessary immediately after installation.

Salix lucida (Shining Willow)
Salix nigra (Black Willow)
Salix purpurea (Streamco Willow)
Salix sericea (Silky Willow)
Salix x cottetii (‘Bankers’ Dwarf Willow)
Sambucus canadensis (Elderberry)
Viburnum dentatum (Arrowwood)
Viburnum lentago (Nannyberry)

WATTLES / FASCINES

Wattles, also known as fascines, are living branches bound together in long tubular bundles. When placed in shallow trenches across the slope of a bank, these structures provide protection from erosion and create a sediment trap. This material provides immediate bank support even prior to root growth. Once established, this live rooting material grows into a living fence-like erosion barrier. Within one growing season, roots and shoots grow along the entire length of the structure, quickly stabilizing the bank.

INSTALLATION NOTES

This technique is simple, effective and can be installed with little site disturbance. Material is placed in 6” wide trenches on banks or slopes parallel to the stream contour and partially covered with soil. Wedge-like dead stakes secure them in place at 2’-3’ intervals. Live stakes can also be used in conjunction with dead stakes to secure the material. Straw mulching the site after installation retains moisture and reduces surface erosion. Irrigating after installation is necessary if the soil is dry.

Salix lucida (Shining Willow)
Salix nigra (Black Willow)
Salix purpurea (Streamco Willow)
Salix sericea (Silky Willow)
Salix x cottetii (‘Bankers’ Dwarf Willow)
Sambucus canadensis (Elderberry)
Viburnum dentatum (Arrowwood)
Viburnum lentago (Nannyberry)

DEAD WEDGE STAKES

Dead wedge stakes are pieces of hardwood cut into long wedges to secure wattles, brush mattresses and other applications of soil bioengineering and erosion control measures.

AVAILABLE SIZES

1 1/4″ x 3 1/4″ X 2 1/2′ long, wedge-like dead stakes – $0.95 each

LIVE WHIPS

Whips are slender, live woody shrub material. Whips are well suited for very moist areas of stream edges and commonly used in conjunction with gabion structures, riprap and geofabric.

INSTALLATION NOTES

Push whips into the ground as far as they will go without breaking. At least two-thirds of the whip should be covered with soil. Whips can be installed either by laying them on an angle or planting them erect in the soil. When using whips with hard structures, be sure they are long enough to reach into the soil and moisture behind or below the structure. (Example: If installing whips through riprap, take into account the 3’ riprap depth; therefore, install a 6’ whip at least 2’ into the moist soil behind the stone and 1’ above the riprap surface).

Salix lucida (Shining Willow)
Salix nigra (Black Willow)
Salix purpurea (Streamco Willow)
Salix sericea (Silky Willow)
Salix x cottetii (‘Bankers’ Dwarf Willow)
Sambucus canadensis (Elderberry)
Viburnum dentatum (Arrowwood)
Viburnum lentago (Nannyberry)

UNROOTED CUTTINGS

Cuttings of dormant, live sections of advantageous rooting species suitable for sticking directly in the ground for establishment of growing plants.

INSTALLATION NOTES

Cutting should be buried two-thirds of the length in the soil. A pilot hole may be required in some situations.

Salix lucida (Shining Willow)
Salix nigra (Black Willow)
Salix purpurea (Streamco Willow)
Salix sericea (Silky Willow)
Salix x cottetii (‘Bankers’ Dwarf Willow)
Sambucus canadensis (Elderberry)
Viburnum dentatum (Arrowwood)
Viburnum lentago (Nannyberry)

ROOTED CUTTINGS

Rooted cuttings of dormant, live sections of species suitable for planting directly in the ground for fast establishment of growing plants.

INSTALLATION NOTES

Cutting should be planted in the ground with the root collar under the soil’s surface. This can be achieved with a standard shovel or a slitting tool.

Salix lucida (Shining Willow)
Salix nigra (Black Willow)
Salix purpurea (Streamco Willow)
Salix sericea (Silky Willow)
Salix x cottetii (‘Bankers’ Dwarf Willow)
Sambucus canadensis (Elderberry)
Viburnum dentatum (Arrowwood)
Viburnum lentago (Nannyberry)

POSTS

Posts are dormant, live woody cuttings of a species with the branches trimmed off. These differ from live stakes in that they come in lengths in excess of 4’ and in larger diameters than live stakes.

INSTALLATION NOTES

Install posts during their dormancy (late fall to early spring). Do not allow them to dry out. Soaking before planting significantly increases survival and growth rate. Dig a hole and plant the post with at least two-thirds of its length underground. Plant stakes randomly or 3’-6’ apart on triangular spacing. Tamp the soil down around the posts and water. If a long dry spell or hot weather is expected after planting, irrigation may be warranted.

Salix lucida (Shining Willow)
Salix nigra (Black Willow)
Salix purpurea (Streamco Willow)
Salix sericea (Silky Willow)

HELPFUL TIPS FOR YOUR BIOENGINEERING PROJECT

Ernst Seeds bioengineering products are dormant live material. If the material cannot be installed immediately when it arrives at the site, it must be properly stored. Place material out of direct sunlight in a cool, wet place, such as under straw or burlap. If packaged, open the pallets, boxes and plastic bags so the material can be thoroughly watered. Do not allow the material to dry out. Soaking before planting significantly increases survival and growth rate. Planting is best done during dormancy.

For best survivability, the material should be planted during the dormant season, November 1st-April 30th. We do not guarantee any of our bioengineering material from May 1st- October 31st.

Overseeding and mulching a completed bioengineered project with the appropriate seed mixes protects the soil surface from erosion while adding biodiversity to the site. The following mixes are excellent for this purpose: ERNMX-122 (FACW Wetland Meadow Mix), ERNMX-123 (Native Upland Wildlife Forage & Cover Meadow Mix), and ERNMX-138 (Wildlife Food & Shelter Mix).

Live Stake and Branch Layering Cross-Sections courtesy of United States Department of Agriculture, Natural Resources Conservation Service (NRCS), Engineering Field Handbook, December 1996, Chapter 16, “Streambank and Shoreline Protection”, pp. 16-13 and 16-20. Special thanks to John McCullah, Salix Applied Earthcare, for allowing us to use the information in his Bio-Draw software. More information is available at Bio-Draw Software.

DISCLAIMER: The information in this review of practices is the result of more than 50 years of experience in seed production. Ernst Conservation Seeds has been supplying seeds and consulting in the reseeding of tens of thousands of acres of roadsides, surfacemined lands, conservation and restoration sites in eastern North America, as well as growing and supplying seed and consulting in the planting of hundreds of thousands of acres of CRP/CREP-related areas for erosion control and wildlife habitat. All of these practices are opinion only and our best advice as a result of these experiences. These recommendations do not cover all of the conditions that will be encountered in the field. All of the information is for individual consideration. Ernst Conservation Seeds is not responsible for conditions that will be encountered in individual situations. The use of brand names does not represent our endorsement of a specific product; rather, it represents our experience only and has not necessarily been replicated in peer-reviewed research. The use of chemical pest control agents is subject to manufacturers’ instructions and labeling, as well as federal, state and local regulations.