Coir Erosion Control: Mats, Logs and Blankets Explained

The short answer: coir erosion control products are woven meshes, needle-punched blankets and netted fibre rolls (coir logs) made from coconut husk fibre. They hold soil and seed in place while vegetation establishes, then rot away over roughly two to five years, which is longer than straw or jute because coir fibre is 40 to 45 percent lignin. In a 2016 field trial on a 27-degree cut slope, a 700 g/m² coir mesh cut soil loss by 97.9 percent and runoff by 69 percent compared with bare soil (Kalibová, Jačka and Petrů, Solid Earth). The products are not a substitute for permanent armour where flows or waves are strong, and they only work if they stay in firm contact with the ground.

Key facts

Coir fibre contains 40–45 percent lignin, the highest of the common plant fibres; jute has 11–14 percent (Gowthaman, Nakashima and Kawasaki, 2018).

Common coir mesh grades are 400, 700 and 900 g/m² with apertures of about 35, 20 and 12 mm; a UK supplier states a decomposition longevity of 3–5 years (Greenfix Geocoir data).

Coir logs are sold in 300, 400 and 500 mm (12, 16, 20 in) diameters at densities of about 7 and 9 lb/ft³ (roughly 110 and 145 kg/m³), with a stated longevity of 2–5 years (Ferguson Waterworks data sheets, 2025).

Fibre rolls must be trenched in and staked every 1.2 m (4 ft); they are not effective unless in contact with soil (US EPA stormwater BMP fact sheet, 2021).

What coir erosion control products are

Coir is the fibre from the husk of the coconut. Long, stiff "bristle" fibre is spun into twine and woven into open meshes, or needle-punched into dense blankets; loose fibre is packed into tubular netting to make logs. The raw material is the same fibre CVM supplies as coir bristle fibre; the finished erosion products are made by specialist manufacturers who weave, needle or roll it.

The industry groups these products as rolled erosion control products (RECPs). The Erosion Control Technology Council defines an erosion control blanket as "a temporary degradable rolled erosion control product composed of processed natural or polymer fibers" and an open weave textile as the same thing made of "yarns woven into a matrix"; coir appears in both categories and in fibre rolls.

Product	Construction	Typical use
Coir mesh / geotextile (open weave)	Spun coir twine woven into a grid, 400–900 g/m²	Cut and fill slopes, channel banks, dunes; planting through the mesh
Coir blanket (needle-punched)	Coir fibre felted into a dense mat, often with a light net	Slopes where full ground cover is wanted; slower runoff but less open area
Coir log / fibre roll / bioroll	Compressed coir fibre in coir or synthetic netting, 200–500 mm diameter	Toe of banks, lake and pond edges, marsh planting, slope breaks

How coir works on a slope or bank

Bare slopes erode in two ways: raindrops dislodge soil particles, and sheet flow carries them downhill. A coir mesh intercepts the raindrops and breaks the slope into thousands of tiny check dams, one at every twine. Water slows, more of it infiltrates, and the sediment it carries settles behind the yarns. The 2002 ISCO conference paper by De Silva describes exactly this: the mesh "gives the grass plenty of room to grow and at the same time provides larger number of check dams per square metre", then decomposes into mulch once roots have taken over the job.

Coir logs do the same at the toe of a bank. Placed along the waterline and staked, they absorb small waves and shallow flow, trap sediment, and provide a moist bed into which reeds, sedges and willows can root. As the fibre breaks down, the plant roots become the permanent protection.

The important word is temporary. The Virginia Institute of Marine Science states the test of a fibre-log project plainly: it succeeds if the planted marsh is still there after the logs have biodegraded. If vegetation cannot hold the site on its own, a permanent structure is needed instead.

Typical specifications

Coir mesh and blankets

Manufacturers grade coir meshes by mass per unit area. Three published product lines show how consistent the grades are:

Grade	Mass	Aperture	Open area	Working life (supplier)	Source
400	400 g/m²	35 × 35 mm	65 %	3–4 years	Kalibová et al. (C400 product)
700	700 g/m²	20 × 20 mm (16 × 16 mm for the Greenfix CN700)	50 %	3–7 years	Kalibová et al. (C700); Greenfix
900	900 g/m²	12 × 12 mm	not stated	3–5 years	Greenfix Geocoir

Tensile strength is the figure engineers most often ask for. The Greenfix CN700 data sheet gives 14 kN/m in the ends (warp) direction and 11 kN/m in the picks (weft) direction, tested to DIN 53857, with 19–24 percent elongation. Other suppliers test to ASTM D6818-21, "Standard Test Method for Tensile Properties of Rolled Erosion Control Products". The two test methods are not interchangeable, so check which one a sheet quotes before comparing products. Also ask whether the values are minimum average roll values or typical values; most coir sheets state typical values.

The fibre itself is stretchy: reviews quote 100–225 MPa tensile strength and 12–51 percent elongation for single coir fibres, against 393–860 MPa and 1.5–1.8 percent for jute (Gowthaman et al., 2018). That is why coir meshes tolerate settlement without tearing, and why they do not lie as flat as jute.

Coir logs

Two published data sheets from one US distributor set out the standard and high-density grades:

Property	Standard log	High-density log
Fibre fill	100 % coconut fibre	100 % coconut fibre
Netting	Biodegradable coir twine, 50 × 50 mm (2 × 2 in) mesh	Same
Nominal diameters	300, 400, 500 mm (12, 16, 20 in)	Same
Nominal lengths	3, 3.7, 6 m (10, 12, 20 ft)	Same
Density	7.0 lb/ft³ (about 112 kg/m³)	9.0 lb/ft³ (about 144 kg/m³)
Unit weight	5.0 / 9.0 / 15 lb per ft (7.4 / 13.4 / 22 kg/m)	7.0 / 12.5 / 19.5 lb per ft (10.4 / 18.6 / 29 kg/m)
Stated water velocity	8 / 12 / 15.2 ft/s (2.4 / 3.7 / 4.6 m/s) by diameter	Same
Stated longevity	2–5 years	2–5 years

(Ferguson Waterworks coir log technical data sheets, 2025. Metric conversions are ours.) The standard grade is recommended for "low energy site usage such as streams, ponds, and other concentrated flow areas"; the high-density grade for "lakes, streambanks, bayshores". A UK supplier lists 200, 300 and 400 mm diameters in 3–6 m lengths (Greenfix Coir Rolls). The velocity ratings are manufacturer statements, not independent test results, and they assume correct staking.

How long coir lasts

Supplier figures cluster at 2–5 years for logs and 3–5 years for mesh, with one range as wide as 3–7 years for 700 g/m² mesh (Kalibová et al., Table 2). The academic literature is less generous: Gowthaman et al. (2018) report coir textile retaining only 22 percent of its tensile strength after seven months in one application, and note that rapid loss of strength limits its use. The explanation for the spread is that degradation depends on moisture, temperature, soil biology and whether the fibre is buried or exposed. For design purposes, assume the product carries load for one to two growing seasons and treat anything beyond that as a bonus; choose the vegetation so that it has taken over by then.

Installation basics

The US EPA's 2021 stormwater fact sheets, which draw on Montana DOT, City of Seattle and Clean Water Services manuals, give the clearest public guidance.

Mesh and blankets on slopes

Grade the slope smooth, remove rocks and clods, and seed or plant first. The mesh goes on top of the seed.
Dig an anchor trench at the crest, lay the top edge in it, staple, backfill and compact. Specific trench depths vary by jurisdiction; the EPA directs installers to local manuals for "material orientation, edge overlap, anchoring, and stake or staple spacing".
Unroll down the slope, not across it, and keep the material loose enough to follow the ground. The EPA's rule is that the material "should maintain firm, continuous contact with the soil"; if there is a gap, "erosion will occur underneath the material".
Overlap adjacent rolls in the direction of flow and pin with biodegradable or steel staples at the spacing the manufacturer specifies, more closely in channels and at overlaps.
Inspect after storms and re-pin or re-cover any lifted edges.

Coir logs on banks and slope breaks

Run the log along the contour, perpendicular to flow, and turn the ends upslope so water cannot flow round them.
Trench the log in. The EPA quotes a minimum of 50 mm (2 in), with Seattle recommending 125–180 mm (5–7 in) on soft or loamy soils and 75–125 mm (3–5 in) on hard, rocky ground. In practice a coir log should sit in a trench about one third of its diameter so the toe is buried.
Stake every 1.2 m (4 ft) with wooden stakes at least 19 mm (3/4 in) thick, driven at least 300 mm (12 in) into the ground, through or either side of the log. VIMS says tidal installations should be "aggressively staked on both sides using hardwood stakes only".
Where several rows are used on a slope, Montana DOT spacing for 200 mm (8 in) rolls is 3 m (10 ft) apart on 1:1 slopes, 6 m on 2:1, 9 m on 3:1 and 12 m on 4:1 or flatter. Larger coir logs are spaced according to the manufacturer's tables.
Plant into or immediately behind the log. VIMS notes that planting into the log is not always needed because surrounding vegetation readily grows into it, but it should be used together with planted marsh or bank grading, never alone.
Inspect while the site is active, remove sediment when it reaches one third of the log height, and re-stake any log that has lifted.

Coir compared with jute, straw and synthetics

Property	Coir mesh / log	Jute mesh	Straw or straw-coconut blanket	Synthetic turf reinforcement mat
Lignin content of fibre	40–45 %	11–14 %	low	not applicable
Fibre tensile strength	100–225 MPa, 12–51 % elongation	393–860 MPa, 1.5–1.8 % elongation	low	high
Supplier working life	2–5 years (3–7 years quoted for 700 g/m²)	1–2 years	months to about a year	permanent, non-degradable
Water absorption	130–180 % of fibre mass	higher than coir	high	negligible
Indicative material price (2016, EU)	EUR 0.89–1.29/m² (400 g), 1.29–2.09/m² (700 g)	EUR 0.61–0.96/m² (500 g)	not in the study	not in the study
End of life	Rots in place, adds organic matter	Rots in place	Rots in place	Must be left in place or removed to landfill

Sources: Gowthaman et al. (2018) for fibre properties; Kalibová et al. (2016) for working life and prices; US EPA (2021) for synthetic geotextile disposal.

Coir versus jute. The Czech trial is the best direct comparison. In the laboratory on a 9-degree impermeable bed, jute (500 g/m²) reduced runoff more than either coir mesh. In the field on a 27-degree gravelly loam cut, 700 g/m² coir cut runoff to 31 percent of the bare plot while jute only reached 62 percent, yet jute still gave the lowest soil loss (0.6 percent of control versus 2.1 percent for coir 700 and 6.2 percent for coir 400). The authors attribute the difference to jute absorbing more water and lying flatter on the soil, and coir's stiffer fibres creating "higher obstacles for overland flow" but poorer soil contact. Their conclusion is that the two heavier products perform comparably, that 400 g/m² coir is consistently the weakest of the three, and that ranking changes with slope and soil. Choose jute where a cheap one-season cover is enough; choose coir where the vegetation will take more than a year or the site is wet.

Coir versus straw. The EPA mulching fact sheet shows straw and hay mulch are effective (2 tons per acre of hay reduces soil loss by 98 percent in Minnesota data) but they are loose and are washed away in concentrated flow, so they are limited to gentle slopes and must be netted or tackified near water. Straw blankets with a photodegradable net are the cheapest rolled product for short-term cover; coir is chosen where the blanket must outlast one season or sit in flowing water.

Coir versus synthetics. Polypropylene turf reinforcement mats are stronger and permanent. The EPA is blunt about their drawback: synthetic geotextiles "are not biodegradable", many "degrade rapidly when exposed to sunlight", and it "may be necessary to dispose of geotextiles as well as synthetic matting and netting in a landfill". Coir is the choice when the site will be vegetated and a plastic matrix in a river bank or marsh is unacceptable. Where flows exceed what grass roots alone can resist, the honest answer is a TRM, rock or a hybrid, not a thicker coir mat. For the broader picture of how coconut fibre fits into low-impact construction, see our sustainability page.

Evidence from the field

Czech rail corridor, 2016. On the 1:2 cut slope near Klabava described above, three replicated 15-minute storms at 80 mm/h produced no runoff from any of the coir or jute plots during the first event, while the bare control began to run off within 44–792 seconds. Over the trial, coir 700 reduced soil loss by 97.9 percent and coir 400 by 93.8 percent (Kalibová et al.).
Earlier coir trials summarised by the same authors. Sutherland and Ziegler (2007) measured soil loss of 0.4 percent of control under 700 g/m² coir on a 5.5-degree clay slope; Lekha (2004) recorded 0.4–21.9 percent of control under 700 g/m² coir on a 26-degree slope in India; Álvarez-Mozos et al. (2014) found coir beat jute at 45 degrees but not at 60 degrees. Product grade, slope and soil all matter.
Flint Creek watershed, USA. The EPA fibre-roll fact sheet cites a restoration project where planted fibre rolls along creek shorelines increased vegetative cover, stabilised banks and improved water quality (US EPA Section 319 success stories, 2001).
Tidal marshes, Virginia. VIMS reports that fibre logs decay within about 3 to 5 years in tidal settings and recommends them only above mid-tide level at sites with minimal wave and boat-wake action.

Limitations and common failures

Wave and flow energy. Fibre rolls "are not designed to reduce wave energy" (VIMS). The EPA warns against using them in channels experiencing erosion from concentrated flow. Manufacturer velocity ratings of 2.4–4.6 m/s apply to well-staked logs in short events, not to sustained flood flow.
Loss of ground contact. The single most common failure. Bridging over hollows, shallow trenches and too few stakes let water run under the product. VIMS lists "inadequate monitoring and staking" among the main causes of failure.
Slopes that move. Fibre rolls should not be used on slopes subject to creep, slumping or landslide (EPA, citing Clean Water Services). Coir holds surface soil; it does not fix a geotechnical problem.
Steep slopes and jute-type behaviour. On very steep faces water can run through and under a mesh without infiltrating (Álvarez-Mozos et al., as discussed by Kalibová et al.). Combine mesh with brush layering or live stakes above about 1:1.
Degradation faster than planned. If the fibre is wet and warm and the vegetation is slow, the mesh may lose its strength before the roots arrive. Plan planting and irrigation accordingly.
Raw-fibre quality. Mesh strength depends on the twine, which depends on fibre length and cleanliness. For a coarse structural component in soil mixes rather than textiles, see coconut husk chips.

Specifying and sourcing

A usable specification states the function (surface protection until vegetation, or toe protection for a planted bank), the grade by mass per unit area, minimum tensile strength in both directions with the test method named, and for logs the diameter, density and netting material. It also fixes trench depth, stake spacing, overlap and the requirement for continuous ground contact, and names who inspects after storms during the first two seasons.

Ask the supplier about the fibre, too. Mesh strength depends on the twine, and long, clean bristle fibre spins into stronger yarn than short fibre mixed with pith. CVM supplies coir bristle fibre to manufacturers of twine, mats and erosion products; we do not make finished geotextiles, but we can describe the fibre's length and cleanliness and discuss what a textile maker needs. Contact us with your requirement.

FAQ

What is coir erosion control matting?

Coir erosion control matting is an open-weave mesh made from spun coconut-husk fibre twine, usually sold in 400, 700 and 900 g/m² grades. It is pinned over seeded slopes and channel banks to absorb raindrop impact, slow runoff and trap sediment until grass or shrubs take over, then decomposes over several years.

How long do coir logs last?

Manufacturers state 2 to 5 years and coastal guidance from Virginia gives about 3 to 5 years in tidal settings. Academic measurements show coir can lose most of its tensile strength within a year in warm, wet conditions. Design so that vegetation has taken over within one to two growing seasons.

Is coir better than jute for erosion control?

It depends on the job. In a 2016 field trial on a 27-degree slope, 700 g/m² coir reduced runoff more than 500 g/m² jute, but jute gave slightly lower soil loss; the authors judged the two comparable. Jute is cheaper and lasts one to two years; coir lasts longer and suits wet sites and planting through the mesh.

What density should a coir log be?

Standard logs are about 7 lb/ft³ (around 110 kg/m³) and are recommended for low-energy streams and ponds. High-density logs are about 9 lb/ft³ (around 145 kg/m³) and are specified for lakes, bay shores and streambanks with more wave or flow energy. Either way the log must be trenched in and staked every 1.2 m.

Can coir logs stop wave erosion on a lake or sea shore?

Only small waves. Fibre rolls are not designed to reduce wave energy and are recommended for sites with minimal wave and boat-wake action, above mid-tide level. On exposed shores they are used behind a sill or breakwater that takes the wave energy, with the logs protecting the planted marsh.

How are coir mats installed on a slope?

Seed first, then anchor the top edge in a trench at the crest, unroll down the slope, keep the mesh in continuous contact with the soil, overlap adjacent rolls in the direction of flow and pin with staples at the manufacturer's spacing. Inspect after storms and re-pin any lifted edges.

Does coir erosion control matting need to be removed?

No. Coir mesh with coir-twine netting is fully biodegradable and is left in place to rot into the soil as mulch. Products with a polypropylene net are only partly biodegradable; the plastic net remains and may need removal where it is unacceptable.

Why does coir last longer than straw or jute?

Coir fibre is about 40 to 45 percent lignin, the highest of the common plant fibres, against 11 to 14 percent in jute. Lignin is hydrophobic and slow for fungi and bacteria to break down, so coir resists rot far longer. Coir is also one of the few natural fibres that tolerates salt water.

Sources

Kalibová, J., Jačka, L., Petrů, J.: The effectiveness of jute and coir blankets for erosion control in different field and laboratory conditions, Solid Earth 7, 469–479 (2016)
Gowthaman, S., Nakashima, K., Kawasaki, S.: A State-of-the-Art Review on Soil Reinforcement Technology Using Natural Plant Fiber Materials, Materials 11(4), 553 (2018)
Hasan, K.M.F., Horváth, P.G., Bak, M., Alpár, T.: A state-of-the-art review on coir fiber-reinforced biocomposites, RSC Advances 11, 10548–10571 (2021)
US Environmental Protection Agency: Stormwater Best Management Practice – Fiber Rolls, EPA-832-F-21-028S (2021)
US Environmental Protection Agency: Stormwater Best Management Practice – Geotextiles, Matting and Netting, EPA-832-F-21-028T (2021)
US Environmental Protection Agency: Stormwater Best Management Practice – Mulching (2021)
Virginia Institute of Marine Science, Center for Coastal Resources Management: Living Shorelines Design Alternatives – Fiber Logs (web guidance, accessed 2026)
Ferguson Waterworks: Standard and High-Density Coir Logs technical data sheets (2025)
Soiltec GmbH / Greenfix: Technical Data Sheet Coir Netting CN 700 (2021)
Greenfix UK: Geocoir and Coir Rolls product pages (accessed 2026)
ASTM International: ASTM D6818-21, Standard Test Method for Tensile Properties of Rolled Erosion Control Products (2021)
Erosion Control Technology Council: Terminology (web page, accessed 2026)
De Silva, G.F.: Coconut Coir Fibre as an Eco-Friendly Renewable Resource for Soil and Water Conservation, 12th ISCO Conference, Beijing (2002)