Title: vegetation by Er. Harish
1Vegetation Establishment
2Exposed soil occurs on all construction sites
3Soil Stabilization
- Soil stabilization is the component that combines
with runoff control to be the concepts that limit
or control erosion. - Every effort should be made to keep the soil in
place and limit its migration within the project
area to minimize the need for sediment control.
4Protect Surface
Vegetative Soil Cover
Non-Vegetative Cover
Temporary Seeding
Mulching
Permanent Seeding
Riprap Slope Protection
Topsoiling
Sodding
Protecting Vegetation
Rec. Area Improvement
Dune Stabilization
5This site was temporary seeded (dormant seeding)
in January, and it germinated by April.
6Seeding Techniques
Its important for the seed to be in direct
contact with the soil.this machine is a drill
seeder.
7Seeding Techniques
Helicopters can distribute seed over a large area.
8Seeding Techniques
This is one of the most common seeding methods
for construction sites.
9Graded 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?
10 Native Regrowth Method
The key to this simple process is that it can
preclude the need for soil amendments, seeding,
and irrigation.
11Sod provides immediate soil cover.
12Protect Existing Vegetation
- Wherever possible, existing vegetation should be
preserved.
Leaving existing vegetation is particularly
important along the site perimeter or adjacent to
water bodies.
13Temporary Seeding
- Purpose Establishment of temporary stand of
grass and/or legume by seeding and mulching soils
that will be exposed for a period grater then one
month but less then 12 months. - Applicability Within the firs 7 days of
suspending works on a grading operation that
exposes erodible sols where such suspension is
expected to last for 1 to 12 month. Such areas
include soil stockpiles, borrow pits, road banks
and other disturbed and unstable areas. - Not for use on areas that are to be left dormant
for more then 1 year. Use permanent vegetative
measures in those situations.
14Specifications
- Ensure proper species are selected for season and
site conditions (review seed mixture used by
inspecting bag labels). - Ensure seeding is done within optimum seeding
dates. - Ensure proper site preparation and sequencing of
seeding operation with other operations. - Ensure proper seedbed preparation including
appropriate top soil materials (loose friable
soil), and use of appropriate seeding equipment. - Use Mulch on those sites when called for or in
seeding outside of approved dates.
15Maintenance
- 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 inch or greater for seed
and mulch movement and rill erosion. - Where seed has moved or where soil erosion has
occurred, determining the cause of the failure.
Repair rills and other areas where soil has been
eroded. Re-seed and re-mulch. Inspect for
evidence of concentrated flows and bring to
attention of site engineer for possible
structural design needs. - Continue inspections until the grasses are firmly
established. Grasses shall not be considered
established until a ground cover is achieved
which is mature enough to control soil erosion
and to survive severe weather conditions
(approximately 80 of surface cover is
vegetated).
16Temporary seeding can be quite cost effective.
17Permanent Seeding
- Purpose To permanently stabilize the soil with
a vegetative cover that will prevent damage from
wind and/or water erosion and sedimentation. - Applicability
- On disturbed or eroded soils have been brought to
final grade or where the suspension of work is
expected to exceed one year, and - Where slopes gradients are no steeper then 21.
for slopes steeper then 21 use slope
stabilization measures that include structural
measures.
18Specifications
- Ensure proper species are selected for season and
site conditions (review seed mixture used by
inspecting bag labels look for pure live seed
percentages and ensure legumes are inoculated). - Ensure seeding is done within optimum seeding
dates. - Ensure proper site preparation and sequencing of
seeding operation with other operations. - Ensure proper seedbed preparation including
appropriate top soil materials (loose friable
soil), and use of appropriate seeding equipment. - Ensure lime and fertilizer have been applied
based upon soil test recommendations or use of
standardized recommendations for species
selected. - Use Mulch on those sites when called for or in
seeding outside of approved dates. - Consider irrigation needs during periods of low
rainfall.
19Maintenance
- 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 inch or greater for seed
and mulch movement and rill erosion. - Where seed has moved or where soil erosion has
occurred, determining the cause of the failure.
Repair rills and other areas where soil has been
eroded. Re-seed and re-mulch. Inspect for
evidence of concentrated flows and bring to
attention of site engineer for possible
structural design needs. - Continue inspections until the grasses are firmly
established. Grasses shall not be considered
established if there is less then 100 plans per
square foot after 4 weeks of growth. If not,
reseed as planting season allows, if not, mulch
area with approved mulch at approved rate. - Allow majority of plants to achieve a height of
at least 6 inches before first mowing and mow
afterwards on a schedule in operation and
maintenance plan.
20Questions