Vegetation Vegetation EstablishmentEstablishment

Exposed soil occurs on all construction sites

Soil StabilizationSoil StabilizationSoil stabilization is the component that Soil stabilization is the component that

combines with runoff control to be the combines with runoff control to be the concepts that limit or control erosion.concepts that limit or control erosion.

Every effort should be made to keep the Every effort should be made to keep the soil in place and limit its migration soil in place and limit its migration within the project area to minimize the within the project area to minimize the need for sediment control.need for sediment control.

Protect SurfaceProtect Surface

Vegetative Soil CoverVegetative Soil Cover Non-Vegetative CoverNon-Vegetative Cover

Temporary SeedingTemporary Seeding

TopsoilingTopsoiling

SoddingSodding

MulchingMulching

Riprap Slope ProtectionRiprap Slope ProtectionPermanent SeedingPermanent Seeding

Protecting VegetationProtecting Vegetation

Rec. Area ImprovementRec. Area Improvement

Dune StabilizationDune Stabilization

This site was temporary seeded (dormant seeding) in January, and it germinated by April.

Drill SeedingDrill Seeding

Seeding TechniquesSeeding Techniques

It’s important for the seed to be in direct contact with

the soil….this

machine is a drill seeder.

Helicopter SeedingHelicopter Seeding

Seeding TechniquesSeeding Techniques

Helicopters can distribute seed over a large area.

Hydraulic SeedingHydraulic Seeding

Seeding TechniquesSeeding Techniques

This is one of the most common seeding

methods for construction

sites.

Graded slopes should be topsoiled and seeded as soon as practical

But what is the problem do you seen with this photo with the sediment barrier?

Native Regrowth Native Regrowth MethodMethod

The key to this simple process is that it can preclude the need for soil amendments, seeding, and

irrigation.

Sod provides immediate soil cover.

Protect Existing Protect Existing VegetationVegetation

Wherever possible, existing vegetation should be preserved.

Leaving existing vegetation is particularly important along the site perimeter or adjacent to water bodies.

Specifications Specifications Ensure proper species are selected for Ensure proper species are selected for

season and site conditions (review seed season and site conditions (review seed mixture used by inspecting bag labels).mixture used by inspecting bag labels).

Ensure seeding is done within optimum Ensure seeding is done within optimum seeding dates.seeding dates.

Ensure proper site preparation and Ensure proper site preparation and sequencing of seeding operation with other sequencing of seeding operation with other operations.operations.

Ensure proper seedbed preparation – Ensure proper seedbed preparation – including appropriate top soil materials (loose including appropriate top soil materials (loose friable soil), and use of appropriate seeding friable soil), and use of appropriate seeding equipment.equipment.

Use Mulch on those sites when called for or in Use Mulch on those sites when called for or in seeding outside of approved dates.seeding outside of approved dates.

MaintenanceMaintenance Inspect seeded areas at least once a week and Inspect seeded areas at least once a week and

within 24 hours of the end of a storm with a rainfall within 24 hours of the end of a storm with a rainfall amount of 0.5 inch or greater for seed and mulch amount of 0.5 inch or greater for seed and mulch movement and rill erosion.movement and rill erosion.

Where seed has moved or where soil erosion has Where seed has moved or where soil erosion has occurred, determining the cause of the failure. occurred, determining the cause of the failure. Repair rills and other areas where soil has been Repair rills and other areas where soil has been eroded. Re-seed and re-mulch. Inspect for evidence eroded. Re-seed and re-mulch. Inspect for evidence of concentrated flows and bring to attention of site of concentrated flows and bring to attention of site engineer for possible structural design needs.engineer for possible structural design needs.

Continue inspections until the grasses are firmly Continue inspections until the grasses are firmly established. Grasses shall not be considered established. Grasses shall not be considered established until a ground cover is achieved which is established until a ground cover is achieved which is mature enough to control soil erosion and to survive mature enough to control soil erosion and to survive severe weather conditions (approximately 80% of severe weather conditions (approximately 80% of surface cover is vegetated).surface cover is vegetated).

Temporary seeding can be quite cost effective.

Permanent SeedingPermanent Seeding Purpose: To permanently stabilize the soil with a Purpose: To permanently stabilize the soil with a

vegetative cover that will prevent damage from vegetative cover that will prevent damage from wind and/or water erosion and sedimentation.wind and/or water erosion and sedimentation.

Applicability: Applicability: On disturbed or eroded soils have been brought to final On disturbed or eroded soils have been brought to final

grade or where the suspension of work is expected to grade or where the suspension of work is expected to exceed one year, andexceed one year, and

Where slopes gradients are no steeper then 2:1. for Where slopes gradients are no steeper then 2:1. for slopes steeper then 2:1 use slope stabilization measures slopes steeper then 2:1 use slope stabilization measures that include structural measures.that include structural measures.

SpecificationsSpecifications Ensure proper species are selected for season and site Ensure proper species are selected for season and site

conditions (review seed mixture used by inspecting conditions (review seed mixture used by inspecting bag labels – look for pure live seed percentages and bag labels – look for pure live seed percentages and ensure legumes are inoculated).ensure legumes are inoculated).

Ensure seeding is done within optimum seeding dates.Ensure seeding is done within optimum seeding dates. Ensure proper site preparation and sequencing of Ensure proper site preparation and sequencing of

seeding operation with other operations. seeding operation with other operations. Ensure proper seedbed preparation – including Ensure proper seedbed preparation – including

appropriate top soil materials (loose friable soil), and appropriate top soil materials (loose friable soil), and use of appropriate seeding equipment. use of appropriate seeding equipment.

Ensure lime and fertilizer have been applied based Ensure lime and fertilizer have been applied based upon soil test recommendations or use of upon soil test recommendations or use of ‘standardized’ recommendations for species selected.‘standardized’ recommendations for species selected.

Use Mulch on those sites when called for or in seeding Use Mulch on those sites when called for or in seeding outside of approved dates.outside of approved dates.

Consider irrigation needs during periods of low rainfall.Consider irrigation needs during periods of low rainfall.

MaintenanceMaintenance Inspect seeded areas at least once a week and within 24 Inspect seeded areas at least once a week and within 24

hours of the end of a storm with a rainfall amount of 0.5 hours of the end of a storm with a rainfall amount of 0.5 inch or greater for seed and mulch movement and rill inch or greater for seed and mulch movement and rill erosion.erosion.

Where seed has moved or where soil erosion has occurred, Where seed has moved or where soil erosion has occurred, determining the cause of the failure. Repair rills and other determining the cause of the failure. Repair rills and other areas where soil has been eroded. Re-seed and re-mulch. areas where soil has been eroded. Re-seed and re-mulch. Inspect for evidence of concentrated flows and bring to Inspect for evidence of concentrated flows and bring to attention of site engineer for possible structural design attention of site engineer for possible structural design needs.needs.

Continue inspections until the grasses are firmly Continue inspections until the grasses are firmly established. Grasses shall not be considered established if established. Grasses shall not be considered established if there is less then 100 plans per square foot after 4 weeks of there is less then 100 plans per square foot after 4 weeks of growth. If not, reseed as planting season allows, if not, growth. If not, reseed as planting season allows, if not, mulch area with approved mulch at approved rate.mulch area with approved mulch at approved rate.

Allow majority of plants to achieve a height of at least 6 Allow majority of plants to achieve a height of at least 6 inches before first mowing and mow afterwards on a inches before first mowing and mow afterwards on a schedule in operation and maintenance plan.schedule in operation and maintenance plan.

QuestionsQuestions