ESCA BC · Living treatments in practice
Soil Bioengineering for Surface Erosion Control
Bare soil washing away? Water finding a path down a slope? Start with what is moving the soil, then choose the preparation, living treatment and temporary protection that fit the site.
These field notes support Nathan Polster’s ESCA BC discussion and give you a starting point for exploring the methods afterward.
Follow the water before choosing a treatment
Rain striking bare ground, diffuse runoff over a slope and water concentrated into rills call for different responses. Look uphill as well as at the damaged patch: a road, roof outlet, ditch or compacted surface may be delivering water that overwhelms the treatment below.
Plants need conditions in which they can establish. Surface preparation can create those conditions; temporary cover can protect soil during the wait. Where runoff is concentrated, assess its source, route and a safe outlet. Do not simply redirect the problem onto another area.
Start with the problem you can see
Use these combinations to frame a site assessment. They are possibilities to investigate, not automatic treatment recommendations.
Exposed soil
Consider suitable mulch or a blanket for immediate protection, paired with native planting or seeding. Rough-and-loose preparation may help where surface disturbance is safe.
Check first: Check moisture, plantable soil and protection through the first storms.
Runoff moving over slopes
Assess whether runoff is diffuse or concentrated. Suitable surface roughness and living rows may complement vegetation where flow remains within the treatment’s intended function.
Check first: An outlet, ditch discharge or increasing flow needs drainage assessment; planting alone is not the answer.
Small rills
Address the source and flow path before repairing the surface. Temporary cover, prepared microsites and vegetation may help protect the repaired area.
Check first: Growing rills, headcuts or repeated washout need specialist reassessment; do not install a generic living check dam.
Dry or compacted ground
Assess safe loosening or rough-and-loose preparation, native stock suited to dry exposure, and mulch or establishment watering. Supported brush-layer microsites may fit some sites.
Check first: Do not assume willow will root without dependable moisture, or that digging into a slope is safe.
Disturbed riparian surfaces
Suitable live stakes, living rows and native rooted planting can complement surface protection on assessed, stable margins. Protect retained vegetation and plan careful access.
Check first: Separate rainfall/runoff erosion from stream scour, toe undercutting and bank movement. Confirm ecological constraints and any necessary specialist input before work.
Seven methods, with different jobs
Living bioengineering uses live plant material within an assembly intended to perform a physical function. Living revegetation builds plant cover and roots through planting or seeding. Supporting measures prepare the ground or protect it while the living parts establish. These roles work together.
Rough-and-loose surface preparation
Create an irregular, loosened surface with hollows and mounds instead of leaving smooth, compacted ground. The microsites can catch seed, litter and moisture and create places for vegetation to establish.
Where it may fit: Exposed disturbed soil and compacted reclamation ground where safe surface disturbance is appropriate. It can support natural recruitment, rooted planting or live staking.
Butler Bros combined rough-and-loose treatment with live staking. The archive shows later woody cover; it does not quantify erosion reduction or prove deep slope stability.
Explore the PES source →Site requirements, limits and establishment care
Moisture, soil, season and access
Assess the soil and available fine material, seasonal moisture and nearby seed sources. Machine access and safe working ground are usually needed; wet or frozen ground may constrain treatment. Roughness does not make every substrate a viable seedbed.
When another approach or specialist is needed
Avoid applying it as a recipe to moving slopes, sensitive roots, buried services or areas where disturbed soil or ponding would create another problem. Slope stability, drainage and safe machine access may require geotechnical or other specialist input.
What happens now and over time
Microsites exist immediately; plant cover develops over subsequent growing seasons. Recruitment may be slow where seed supply or moisture is limited.
Maintenance and monitoring
Inspect after significant rain for connected runoff paths, sediment escape and renewed compaction. Track recruitment and bare areas through the growing season; adapt planting or protection if recovery is falling short.
Further reading: PES rough-and-loose method · Butler Bros PES project archive
Live staking
Install living, rootable woody cuttings where they can maintain soil contact and reach dependable moisture. If they establish, roots and shoots add vegetation and resistance to surface erosion over time.
Where it may fit: Moist disturbed surfaces and suitable riparian margins, or prepared slope microsites. Useful within a broader treatment when plants can establish before the surface erodes away.
At Clam Bay, live staking was directed to moisture-accessible parts of resistant till, with native planting and establishment care elsewhere. That shoreline project also addressed issues beyond surface erosion.
Explore the PES source →Site requirements, limits and establishment care
Moisture, soil, season and access
Match the species and source material to the site. Plan harvesting and installation around dormancy and workable soil; protect cuttings from drying during handling. Resistant ground may need pilot holes. Assess summer moisture and access for watering and inspection.
When another approach or specialist is needed
Isolated stakes do not provide continuous immediate surface cover. They are unsuitable as the sole response to concentrated flow, major scour, dry ground with no accessible moisture or deep slope movement. Soil resistance and sensitive watercourse work may need specialist assessment.
What happens now and over time
Rooting and shoots may begin in the first growing season. Wider root networks and cover develop over later seasons; visible shoots alone do not demonstrate adequate rooting or erosion resistance.
Maintenance and monitoring
Check moisture, loosening, exposed stems and erosion around stakes. Monitor live growth, browsing and competition, and record failures as well as growth. Plan watering, protection and replacement where needed.
Further reading: PES live staking · Clam Bay PES project record · PES harvesting cuttings
Live willow wattles and fascines
Live woody rows can interrupt surface-material movement and provide places for plants to establish. PES wattle fences support horizontal cuttings behind uprights; fascines are tied bundles of rootable branches placed with soil contact. The terms describe different assemblies.
Where it may fit: Suitable moist slopes with surface raveling or diffuse runoff, as one part of an assessed treatment. Layout must account for where water will go around, through and beyond each row.
The PES wattle-fencing archive documents a living fence treatment over time. This is a wattle-fence example; it does not document a bundled-fascine installation.
Explore the PES source →Site requirements, limits and establishment care
Moisture, soil, season and access
Use suitable rootable material, dependable moisture, good soil contact and a safe anchoring substrate. Coordinate dormant-season cutting supply with workable ground, crew access and backfilling. The structure needs an installation and inspection plan.
When another approach or specialist is needed
A live fence or bundle is not a drainage channel, universal check dam or structural retaining wall. Flow bypass, undermining or overloaded rows can create new erosion. Concentrated runoff, unstable slopes and stream scour require appropriate engineering or hydrological input.
What happens now and over time
The installed assembly can provide a physical break immediately when correctly designed and secured. Rooting and woody cover develop over growing seasons if the living material establishes.
Maintenance and monitoring
Inspect row ends, anchorage, soil contact, sediment accumulation and water paths after storms. Check rooting conditions and live growth through dry periods; repair undermining or bypass and reassess failed sections.
Further reading: PES wattle fencing · NRCS Plant Materials Technical Note 38 (2006)
Brush layers
Conventional brush layers place live branch cuttings into prepared benches with their bases in soil and tips emerging from the slope. PES modified brush layers use supported terraces or microsites, including logs and live material, to suit different surface conditions.
Where it may fit: Surface raveling and disturbed slopes where a designed bench or supported planting pocket can retain material and allow establishment. The modified approach may suit some drier sites or limited machine access.
PES’s modified brush-layer source material shows supports, cuttings and backfill. It illustrates the modified method; a conventional brush-layer project case is not presented here.
Explore the PES source →Site requirements, limits and establishment care
Moisture, soil, season and access
Check available moisture, plant material, soil contact, support and anchorage. Living cuttings still need suitable rooting conditions, even on a drier site. Coordinate the cutting season, safe excavation or hand work, material supply and aftercare access.
When another approach or specialist is needed
Cutting benches can disturb a slope. Logs and branches do not resolve deep instability, high-energy scour or an unaddressed runoff source. Assess stability, support loads and safe access with the relevant specialist before choosing the assembly.
What happens now and over time
The supported assembly can retain some surface material at installation. Vegetation and rooting develop over following growing seasons; they are conditional on successful establishment.
Maintenance and monitoring
Inspect supports, displacement, exposed cuttings, settlement and erosion between terraces. Watch for water concentration, moisture stress and browsing; repair or revise the treatment when its intended function is not developing.
Further reading: PES modified brush layers · NRCS Soil Bioengineering Plantings specification (2017)
Native rooted planting
Plant nursery-grown or appropriately salvaged native plants with existing roots. Species matched to the site can build surface cover, litter and root networks while adding vegetation suited to the restoration setting.
Where it may fit: Prepared exposed soil, drier slope zones where willow cuttings may not fit, and disturbed riparian surfaces after the water and surface-movement problems have been addressed.
Clam Bay combined upper-slope native rooted planting with mulch, drip irrigation and deer protection. The records document installation and care measures, without establishing a survival percentage.
Explore the PES source →Site requirements, limits and establishment care
Moisture, soil, season and access
Match stock to soil, drainage, exposure and seasonal moisture. Prepare plantable microsites and plan installation for workable conditions with dependable moisture or an agreed watering supply. Crews need access for planting, watering and maintenance.
When another approach or specialist is needed
Rooted stock does not instantly protect all soil between plants. Concentrated flow, scour, severe compaction and moving ground can defeat planting. Species selection, riparian constraints and slope hazards may require ecological or engineering input.
What happens now and over time
Roots are present at planting, but they need to grow into surrounding soil. Cover and wider rooting develop over multiple seasons; the establishment period still needs protection.
Maintenance and monitoring
Check root-zone moisture, plant condition, browsing and invasive competition. Maintain irrigation or mulch where specified, record losses and bare areas, and revisit species or site preparation when failures are clustered.
Further reading: Clam Bay PES project record
Seeding
Apply a site-appropriate seed mix to a receptive seedbed so vegetation can establish cover and roots. Seed itself offers little immediate soil protection; temporary protection may be needed while it germinates and grows.
Where it may fit: Exposed soil that can retain seed and provide germination moisture. It can complement woody planting or prepared microsites where the seed mix supports the intended plant community.
Butler Bros is an example of adaptation: seeded cover remained alongside exposed, eroded ground before PES changed the approach. This does not show that seeding fails on every site or verify the original seed mix.
Explore the PES source →Site requirements, limits and establishment care
Moisture, soil, season and access
Check soil contact, compaction, germination requirements, seasonal moisture and application access. Select species for the site and restoration objective; plan how seed will stay in place and how young growth will get water.
When another approach or specialist is needed
Seeding alone is a poor response to active rilling, concentrated flow or a seedbed that is moving or persistently dry. Dense competitive cover can also impede intended woody recruitment. Seek qualified seed and erosion-control advice where establishment or protection is uncertain.
What happens now and over time
Germination timing depends on species and conditions. Useful cover needs growth beyond germination; neither seed application nor a green photograph proves that erosion is controlled.
Maintenance and monitoring
Inspect seed retention, patchy emergence, bare soil and renewed erosion after rain and during establishment. Identify the cause of gaps before reseeding, and manage unwanted competition.
Further reading: Butler Bros PES project archive · EPA permanent seeding fact sheet (2021)
Temporary blankets or mulch
Cover vulnerable soil while vegetation establishes. Blankets provide an anchored cover; mulch can cushion rainfall impact and support establishment moisture when the material and application suit the site.
Where it may fit: Exposed soil between young plants, prepared seedbeds and vulnerable surfaces that need temporary protection. Select the material for the actual rainfall, slope and runoff conditions.
Clam Bay records mulch as part of establishment care. This example documents mulch; it does not establish the performance of a particular blanket product.
Explore the PES source →Site requirements, limits and establishment care
Moisture, soil, season and access
Assess soil contact, anchoring, runoff, material suitability and access for installation and repairs. Coordinate coverage with seeding or planting, and check product guidance and relevant wildlife or habitat constraints. Mulch and blankets are not interchangeable on every slope.
When another approach or specialist is needed
Loose mulch can move, and poorly fitted blankets can be lifted or undermined. Neither resolves deep slope movement or substitutes for a designed concentrated-flow treatment. Get erosion-control or product-specialist input for demanding conditions.
What happens now and over time
Protection starts after suitable material is correctly installed. Its useful life must bridge the establishment period; durability varies by material, exposure and site conditions.
Maintenance and monitoring
Check contact, anchor security, exposed edges, displaced mulch and erosion underneath after rain. Restore failed coverage and follow the specified removal or degradation plan; inspect for impeded plant growth.
Further reading: Clam Bay PES project record · EPA matting and netting fact sheet (2021) · EPA mulching fact sheet (2021) · BC transportation environmental reference documents
Make the methods work together
The immediate job is to protect the ground and create workable establishment conditions. The longer job is to develop living cover and roots, and keep checking whether the original erosion problem is being addressed.
Water and ground first
Assess runoff delivery, surface movement, compaction and moisture. Resolve drainage or stability questions before preparing microsites or installing living structures.
Give young plants a chance
Choose compatible living treatments and any needed temporary cover. Plan material supply, timing, irrigation and browse protection as part of the treatment.
Look beyond green cover
Check erosion, runoff paths, soil contact and plant condition after significant weather and through dry periods. Repair failures and revisit the cause when the same damage returns.
Butler Bros: preparation and live staking were used after seeded cover coexisted with exposed, eroded areas. Later archive photos show woody development, without quantifying treatment performance.
Clam Bay: native planting, moisture-targeted staking, mulch, irrigation and deer protection served different establishment needs. Its shoreline context also involved problems outside this surface-erosion overview.
Project photographs are observations, not measurements of survival, sediment reduction or deep slope stability.
A short site-assessment checklist
Bring photographs of the damaged ground and the area above it, along with observations from rain events and dry periods. Note what changed and when.
- Where does water arrive from, and where can it leave safely?
- Is soil being washed from the surface, rilling, scoured at the toe, or moving as a larger mass?
- What are the soil, compaction, drainage and summer moisture conditions?
- Which native plants already fit the exposure and moisture zones?
- Can crews and equipment work safely without damaging retained vegetation?
- Are watercourses, structures, services or sensitive habitat close to the work?
- What protection is needed before living cover and roots develop?
- Who will water, inspect, maintain and record the treatment’s condition?
Discuss your project with PES
Tell us what the water and soil are doing, what has already been tried, and how the site can be accessed. We can discuss whether living treatments fit the problem and what other input may be needed.
Discuss your project with PES →Keep exploring
- PES field methods
- Project examples and archive records
- Papers and further resources
- Harvesting and handling living cuttings
Sources and further reading
This resource draws on PES method pages, project records and the ESCA preparation notes. NRCS and EPA guidance supplements method definitions and establishment/protection considerations; it does not establish BC design requirements.
NRCS Plant Materials Technical Note 38 (2006) · NRCS Soil Bioengineering Plantings specification (2017) · EPA permanent seeding fact sheet (2021) · EPA matting and netting fact sheet (2021) · EPA mulching fact sheet (2021) · BC transportation environmental reference documents