Willow Fascines POLLUTANTS ADDRESSED: Nutrients and Organics, Sediments, Salinity
DESCRIPTION: Willow wattles or live fascines are cigar or sausage-like bundles of live cuttings tied together and inserted into a shallow trench dug into the streambank. Plants will sprout and create a dense matrix of roots stabilizing the slope of the bank. LOAD REDUCTION MECHANISM: Nutrients/Organics Management- Willow and associated plants will take up nutrient materials. Salinity Reduction- Willow and associated plants will take up salts. Sediment Reduction – Plant roots will stabilize stream bank, reducing sediment production.
ALTERNATIVE MANAGEMENT MEASURES: Brush Mattress Erosion Control Fabric Pole Plantings Seeding Tree Planting Vertical Bundles PERMITTING REQUIREMENTS: Generally none if installed by hand. If part of an extensive stream project or if mechanical means are used, a permit under Sections 404 & 401 of the Clean Water Act may be required.
LAND USE CLASSIFICATION: Agricultural lands Grazing lands Urban areas ADDITIONAL BENEFITS: Promotes development of riparian plant communities along the streambank which will also provide habitat for other riparian species.
Arid Southwest BMP
POTENTIAL TREATMENT AREAS: Streamside
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Willow Fascines POLLUTANTS ADDRESSED: Nutrients and Organics, Sediments, Salinity
Level 300: MILD ENGINEERING LOAD REDUCTION POTENTIAL: LOW
MEDIUM
4. Rooting hormones and fertilizers do not significantly improve success for the cost of the materials.
HIGH
ESTIMATED TIME FOR LOAD REDUCTION: IMMEDIATE
MONTHS2 YEARS
5. Never disturb the site unnecessarily. Remember the goal is to stabilize a site. The less it is disturbed, the easier it will be to restore.
> 2 YEARS
EXPECTED MAINTENANCE: LOW
MEDIUM
Riparian Planting Zone: Toe and Bank Zones.
HIGH
ESTIMATED COST: LOW
MEDIUM
HIGH
PLANNING AND IMPLEMENTATION: 1. Coyote willow (Salix exigua) is a particularly good species for this method because of its' dense root system. Seep willow (Baccharis salicifolia) is another useful species that is widely available.. 2. If this method is used in a highly erodible area, some protection should be placed in front of the wattles to prevent scour. Analysis and calculations of forces will provide guidance for suitable toe protection. In some cases, brush revetment or fiberschines may be adequate, while other situations may require rock. If no other protection is used, the wattle should be 12 to 24 inches in diameter. 3. Another variation of this technique is to cover the wattles with erosion control fabric to prevent the soil from being washed away from the wattles. Secure the fabric under the first wattle. Poles can be planted into the permanent water table between the wattles. The following illustration also shows the use of a rock toe to prevent scour.
Arid Southwest BMP
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