1
Level II: Introduction to DesignLevel II: Introduction to Design
Vegetative Practices for Vegetative Practices for Erosion and Sedimentation Erosion and Sedimentation
ControlControl
Level II: Introduction to Design
Education and Training Certification Requirements for Persons Involved
with Land Disturbing Activities
Issued May 2009
2
Objectives
• Review the vegetative measures • Understand the importance of:
– Developing effective ES&PC plans – Site inventories – Preserving existing vegetation– Selecting proper vegetative measures– The sequence of components – Planning for the entire year – Maintenance of installed practices
3
Key Points
• Excess soil erosion is not inevitable• Vegetation can reduce soil erosion • ES&PC plans are important• Proper planning is required for success • All ES&PC plans should be different• ES&PC plans should not be an afterthought
• ES&PC is a system (vegetative/structural/management)
• Adequate maintenance is required
4
Benefits of Vegetationin Erosion and Sedimentation Control
• Intercepts raindrops• Reduces detachment• Slows runoff• Cleans runoff• Reduces runoff• Increases infiltration• Protects structures, rivers, streams, and ponds• Reduces maintenance of structural practices• Improves aesthetics, soil quality, and wildlife habitat
5
Construction Sites are inhospitable for vegetative growth
Intensive treatment is needed. Pasture planting methods are not effective.
• Topsoil is removed
• Steep slopes• Low soil moisture • Low soil fertility• Acidic soils• Concentrated flow
• Compacted soils
6
Vegetative Practices “Manual for Erosion and Sediment Control
in Georgia”
• Bf Buffer Zone• Cs Coastal Dune Stabilization • Ds1 Mulching Only• Ds2 Temporary Seeding• Ds3 Permanent Seeding• Ds4 Sodding• Du Dust Control • Mb Matting and Blankets• Pm Polyacrylamide• Sb Streambank Stabilization• Tb Tackifiers and Binders
7
Buffer ZoneUndisturbed or planted vegetative strip
•General Buffer – surround sites•Vegetated Stream Buffer – border streams
•Filter sediment & other pollutants•Reduce runoff velocities•Stabilize stream banks•Provide flood protection •Improve fish/wildlife habitat•Reduce construction noise •Improve aesthetics
Bf
8
Coastal Dune Stabilization
(with Vegetation)Planting vegetation on denuded, constructed, or re-nourished dunes
•Permits (local/state/federal) •Fertilization•Planting•Irrigation•Sand fences•Protection from traffic •Maintenance
Cs
9
Disturbed Area Stabilization (With
Mulching Only)Applying plant residues or other suitable materials to protect disturbed soil
• Reduce runoff and erosion• Conserve moisture• Prevent surface compaction• Control undesirable vegetation• Modify soil temperature• Increase biological activity in the soil
Ds1
10
Ds1 - Mulching Only
•On exposed areas left idle for 14 days
•Apply at the appropriate depth
•Must be anchored
•Maintain cover on 90% or more of the soil surface
•Can be used alone for up to 6 months
11
Disturbed Area Stabilization
(With Temporary Seeding)
Ds2Establishing fast growing vegetation for seasonal soil protection
•Reduce soil erosion•Reduce runoff•Increase infiltration•Improve aesthetics•Improve soil quality•Improve wildlife habitat
Browntop millet
12
Required Temporary Seeding
• Rough graded areas • Diversions• Sides of temporary basins• Stockpiled soil• Temporary dams
13
Ds2 - Temporary Seeding
•On all exposed areas left idle for 14 days
•Maintain 90% or more cover
•Can use alone for up to 6 months
•Use permanent vegetation if
protection is needed >6 months
14
Common Plants used for Temporary Cover
Warm season annuals Cool season annuals
-brown top millet -rye -pearl millet -ryegrass -sudan grass -wheat
• Some perennials, such as tall fescue and common bermuda, may also provide quick cover if planted properly
15
Disturbed Area Stabilization (with Permanent Vegetation)
Ds3Planting perennial vegetation (grasses, legumes, vines, shrubs, and trees) on exposed areas
1. Final permanent stabilization
2. Seasonal protection >6 months
16
Permanent Vegetation
Vegetative plans are based on site conditions.
• Site location• Soil characteristics• Topography• Concentrated water flow• Planned land use • Soil fertility• Soil pH
Ds3
17
Components
Grading and shaping InoculantsLime Planting method Fertilizer Seeding depthSeedbed preparation Mulch Species selection Anchoring mulchSeeding rates IrrigationSeeding dates Maintenance
Ds3
18
Soil Acidity (pH)
• Affects plant growth• Almost all soils in Georgia are acidic• Most plants used need a soil pH of 6.0 - 6.5• 1 – 2 T/A of agricultural lime initially• Maintenance lime applications are needed
19
Agricultural Lime
• Does not move rapidly in the soil• Can be lost in runoff
Conventional planting – apply immediately before
seedbed preparation
Hydro-seeding - apply (1) after straw/hay mulch,
(2) with topdressing, or (3) with 2nd year fertilizer
20
Fertilization
1. Initial – immediately before or at planting2. Topdressing – 6 to 8 weeks after planting3. 2nd year – the year after planting 4. Maintenance – each year
• Don’t “plant it and forget it” • Fertilize based on target species• Recommendations are in the “Manual”
21
Fertilizer
Q. What do the numbers mean?
A. The fertilizer analysis
22
Fertilizer Analysis
% Nitrogen % Phosphorous % Potassium
This 50 LB bag contains 30% plant food (15 LB)and 70% filler.
23
Fertilizer
Selection is based on needs of the target species
Ammonium nitrate
(N topdressing for grasses)
Initial fertilizer For legumes
24
Fertilizer for Grasses
Analysis
Initial N - P - K
Topdressing N
Second Yr. N - P - K
Maintenance N - P - K
25
Fertilizer for Grass/Legume
MixturesAnalysis
Initial N - P - KTopdressing NSecond Yr. * - P - KMaintenance * - P - K
*The desired species are legumes*Legumes get ample N from bacteria if the seed are inoculated properly
26
Seedbed Preparation
• A depth of 4 to 6 inches – Incorporate lime and fertilizer– Provides seed-to-soil contact
• Critical for good plant growth – Provides better root growth – Good plant cover requires a good root system
• Not normally needed for hydro-seeding
27
Regional variations:
Climate
&
Soils
28
Seeding Rates for a Quality Stand
• Under-seeding reduces the stand• Over-seeding creates excessive demand for
moisture, nutrients, light, and space
More is not always better
More seed will not overcome poor planting
techniques
29
Species
PLS 1/
Seeding Rate2/
LB/AC Seed/LB Seed/Sq. Ft.
Common bermuda
10 1,800,000 410
Weeping lovegrass
4 1,500,000 140
Tall fescue 50 227,000 260
Bahia 60 166,000 230
Sericea lespedeza
60 350,000 480
1/ PLS = Pure Live Seed 2/ Seeding rate when seeded alone
30
All seed are not equal.
Q. How do we determine how much of a particular seed to plant?
R. Use pure live seed (PLS) rates.
The rates are easy to calculate.
31
Seed Label
32
Pure Live Seed (PLS) Calculations
Step 1: Get information from seed label:
-tall fescue seed
-95% purity
-85% germination
Step 2: Calculate the PLS value of the seed:
PLS = 0.95 x 0.85 = 0.81 or 81%
Step3: Calculate the seeding rate:
50 #/AC = 62 #/AC are needed
0.81
33
Optimum planting dates for Warm Season Plants
Plant common bermuda and weeping lovegrass
in the early spring:
April 1 - May 15
This permits germination, root growth, and plant
development prior to the hot and dry summer.
34
Optimum planting dates for Cool Season Plants
Plant rye, ryegrass, and tall fescue in early fall:
September 1 - October 15
This permits germination,
root growth, and plant
development prior to the
winter cold and spring drought.
35
Plan for the Entire Year
• Construction completion dates are unpredictable– Schedules not always met– Weather and breakdowns cause delays
• Time of year affects plant selection and performance– For both temporary and permanent vegetation– Seeding plans should vary throughout the year
• Be prepared for all seasons
36
For each plan, develop a year-round seeding
plan
• Here is one example of a year-round seeding plan:
January 1 – March 1-Common Bermuda grass
5 LB/AC unhulled and
5 LB/AC hulled&
-Rye½ BU/AC (28 LB)
37
March 2 – June 1-Common Bermuda grass
10 LB/AC hulled
June 2 – September 1-Common Bermuda grass
5 LB/AC hulled and
5 LB/AC unhulled&
-Browntop millet10 LB/AC
38
September 2 – December 31
-Common Bermuda grass10 LB/AC unhulled
and
-Rye
½ BU/AC (28 LB)
39
Some seed germinate (sprout) slowly.
• Some seed coats prevent water absorption– Expands the germination period – Nature’s way to ensure species survival
• ‘Hulled’ seed– Outer seed coat is removed mechanically– Allows water to enter the seed quicker– Faster seed germination
Example: Common Bermuda (a warm season perennial grass)• Use hulled seed for spring/summer plantings for quick cover• Use unhulled seed in fall and winter plantings
(The seed coat will be altered by Nature during the winter.) • Another option: Use a 50-50 mixture of hulled and unhulled seed to
better ensure successful establishment
‘Unhulled’
‘Hulled’
Common Bermuda seed
40
Some seed germinate slowly, even when hulled.
• ‘Hard’ seed are nearly impervious to water • ‘Hard’ seed may remain dormant a long time
• Scarification overcomes seed coat dormancy– Scratches, softens, punctures, or splits the seed coat w/o embryo damage– Enables seed to absorb more water – Scarified seed will sprout faster and provide quicker cover
Example: Sericea lespedeza (a warm season perennial legume)• Use scarified seed for spring/summer plantings
• Use unscarified seed for fall and winter plantings (The seed coat will be altered by Nature during the winter.)
Sericea lespedeza seed
41
For plants that develop slowly, companion plants
are needed.
Sericea lespedeza emergingin weeping lovegrass
Sericea lespedeza 2-3 years later
Other examples are bahia grass and crown vetch.
42
Limit Seeding Rates of Companion Plants
• Annuals are more vigorous and grow faster
• Compete for nutrients, moisture and space
43
Cool Season Companion Plants
Rye is the best winter annual.
It grows best in cold, acidic soils.
Use ½ BU/AC (28 LB).
Do not use ryegrass in seeding mixtures. It is sod forming and too competitive.
44
Mulch is very important!
Dry straw - 2 T/A
or
Dry hay - 2 ½ T/A
This will cover about 75% of the soil surface
45
Disturbed Area Stabilization (with
Sodding)•Establish immediate ground cover with permanent sod•Effective on steep slopes and in concentrated flow areas
Components:-soil preparation-topsoil-lime-fertilizer-anchoring (>3:1 slope)-irrigation-maintenance
Ds4
Cimarron Valley Sod
Sod Solutions
46
Dust ControlControlling surface and air movement ofdust
• Temporary– Temporary plantings– Tackifiers/binders– Mulch– Rough tillage– Irrigation– Barriers – Calcium chloride
• Permanent – Permanent vegetation and stone
Du
47
• Protects young plants • Promotes plant establishment• Helps reduce erosion
-Temporary and permanent blankets-All must be approved by GDOT
Erosion Control Matting and
Blankets
MbProtective coverings used to establish permanent vegetation
48
Mats and Blankets• Slopes steeper than 2.5:1 and 10’ high or higher• Concentrated flow areas• Cuts and fills within stream buffers• Streambanks• Tidal shorelines• Other areas
49
Blankets must be anchored. Start at top of slope and work down.
50
Land application of anionic polyacrylamide astemporary soil binding agent
• To reduce erosion from wind and water• When establishment of vegetation not
feasible• Site specific material• Repeat application if area is disturbed• Do not apply to surface water
Polyacrylamide (PAM)Pm
51
Streambank Stabilization (using Permanent
Vegetation)Using native plant material to maintain or
enhance streambanks
Sb
Before After
52
Streambank stabilization (using Permanent Vegetation)
• Intensive planning
• Native plant materials
• With structural measures
• Labor intensive
• Local, State and Federal permits
• Specialists may be needed
Sb
53
• Holds mulch in place
• Options in “Manual”
Tackifiers and Binders
TbUsed to anchor straw or hay mulch
54
Topsoiling
Stripping, storing, and using topsoil as topdressing prior to seeding and sodding
• Reduces lime and fertilizer needs
• Greatly improves plant growth
Tp
55
Purposes of an ES&PC Plan
1. Describe potential problems on a site
2. Explain and schedule measures
Good planning is required to prevent excess soil erosion and sedimentation
The prevention process starts with a good plan!
56
How long should an ES&PC plan be?
• Depends on:– Site conditions– Size of the project– Potential for on-site and off-site damages
57
Specialists may be needed
• Assistance with ES&PC plans– Severe problems – Streambanks– Coastal dunes– Other concerns
58
Site Inventory• Visit and inventory the entire site
• Consider– Soils– Topography– Existing cover– Drainage patterns– All adjacent areas - streams, homes, and
roads - especially those down hill from the site
59
Once familiar with the site
• You can identify the areas with the highest erosion potential
• You can develop an effective ES&PC plan
60
Vegetative Cover - Most important tool to reduce soil
erosion and runoff• Consider the existing cover
• Some vegetation is more
effective, but all cover
helps reduce soil erosion
• Good planning reduces vegetation costs
61
Trees - Protect those to be left
• Limit equipment and vehicular traffic under tree canopies
• Limit fill around trees – If fill covers a tree’s swollen base, it will
probably die within 1-2 years
62
Easier to reduce erosion than trap sediment
• Reduce the erosion hazard– Limit the time the soil is bare – Do not clear entire site at one time, if possible– Do land clearing in stages– Use temporary cover and mulching to stabilize
disturbed areas before clearing more
63
Plant Selection
• Land use
• Suitability to site
• Time of year planted
• Planting methods
• Maintenance requirements
• Aesthetics
64
Plant Selection• Sericea lespedeza - not good for lawn
• Weeping lovegrass - not good for lawn
• Tall fescue - not good for athletic field
• Ryegrass - not good choice for nurse crop
• Choose plants that:-provide quick and dependable soil protection-will not be a pest later-require the least maintenance-are native to the area, if possible
65
Management Measures
• Zero cost
• Plan work in logical sequence
• Keep materials on hand to limit delays
• Prepare for thunderstorms, especially in summer
66
“Manuals”
• Minimum criteria for planning, installation, and maintenance
• Treating severe problems requires much more
67
Components of Measures
• Each measure has many components
• Follow a logical sequence
68
Temporary Cover - Conventional Seeding
Methods1. Select plants
- location/site/land use/time of year/maintenance
2. Apply agricultural lime
3. Apply initial fertilizer
4. Prepare seedbed to depth of 4 – 6 inches
5. Determine accurate seeding rates
6. Evenly distribute seed with drill or other
method
69
7. Apply mulch or blankets within 24 hours
8. Anchor all mulch materials immediately
9. Apply topdressing fertilizer 6 – 8 weeks
later
10. Repair, reseed, and mulch damaged
areas
11. Maintain cover for desired time
Temporary Cover - Conventional Seeding Methods
70
Permanent Cover - Conventional Seeding
Methods1. Select target plant
- location, land use, site, time of year, maintenance, etc.
2. Determine if seeding mixtures are needed
3. Apply agricultural lime
4. Apply initial fertilizer
5. Prepare seedbed to depth of 4 – 6”
71
6. Determine accurate seeding rates
7. Inoculate all legume seed
8. Evenly distribute seed with drill or other method
9. Apply mulch or blankets within 24 hrs.
10. Anchor all mulch materials immediately
11. Apply topdressing fertilizer 6 – 8 weeks later
12. Apply second year fertilizer year after seeding
13. Apply maintenance fertilizer each year
Permanent Cover - Conventional Seeding Methods
72
14. Apply maintenance lime every few
years
15. Protect from vehicular traffic
16. Mow properly as needed
17. Maintain cover for desired time
18. Repair/reseed/mulch damaged
areas
Permanent Cover - Conventional Seeding Methods
73
Temporary Cover - Hydro-seeding Methods
1. Select target plant - site, land use, location, time of year, maintenance, etc.
2. Determine accurate seeding rates
3. Mix seed, initial fertilizer, and wood cellulose or
paper mulch in a slurry
4. Evenly distribute the slurry within 1 hour
5. Apply straw/hay mulch/blankets within 24 hours
6. Anchor all mulch materials immediately
74
7. Apply agricultural lime
-after mulching or with topdressing fertilizer
8. Apply topdressing fertilizer 6 – 8 weeks later
9. Maintain cover for desired time
10. Repair, reseed, and mulch damaged areas
Temporary Cover - Hydro-seeding Methods
75
Permanent Cover - Hydro-seeding Methods
1. Select plant - location, site, land use, time of year, and maintenance
2. Decide if seeding mixtures will be used
3. Determine accurate seeding rates
4. Inoculate all legume seed with proper bacteria
5. Mix seed, initial fertilizer, and wood cellulose or
paper mulch in a slurry
6. Evenly distribute the seed within 1 hour
76
7. Apply straw/hay mulch/blankets within 24 hrs.
8. Anchor all mulch materials immediately
9. Apply agricultural lime
(a) after mulching
(b) with topdressing fertilizer, or
(c) with 2nd year fertilizer
10. Apply topdressing fertilizer 6 – 8 weeks later
Permanent Cover - Hydro-seeding Methods
77
11. Apply second year fertilizer year after
seeding
12. Apply maintenance fertilizer each year
13. Apply maintenance lime every few years
14. Protect from vehicular traffic
15. Mow properly and as needed
16. Maintain cover for desired time
17. Repair/reseed/mulch damaged areas as
soon as possible
Permanent Cover - Hydro-seeding Methods
78
Plan for MaintenanceVery important!
Begins when first measure is installed
• Schedule maintenance for each practice• Specify each maintenance component• Inspections also identify maintenance needs• Complete repairs immediately• Apply additional practices if needed
79
Planning is Dynamic
• Site Inventory
• Make Decisions
• Application
• Maintenance
• Monitoring
• Revise plan and add practices if needed
80
Visual observations are valuable
81
82
Plant identification is important!
83
Rye
Ryegrass
Early springLate spring-summer
84
Bahia Bermuda Browntop millet
Centipede
85
Tall fescue
Weeping lovegrass
86
Reed Canary Grass
Big Bluestem
87
Indiangrass
Switchgrass
88
Daylilies Liriope (Monkey Grass)
Junipers
89
Crown vetch
Maximilian sunflower
90
Crabgrass
• A weed – not an approved plant species
91
USDA Plant Database
http://plants.usda.gov/
92
Cover is needed
93
94
ES&PC Plan for south of Atlanta
95
96
97
98
99
100
101
1 acre = 43,560 sq. ft.
or 43.56 (1,000 sq. ft.)
2# x 43.56 = 87 #/ac
3# x 43.56 = 131 #/ac
102
Fertilizer rates for temporary cover are
much less than for permanent cover
103
104
4 oz.
1.2 LB
105
106
Maintenance is important
Fertilizer and lime applications are needed.
107
Mowing Problems
108
Summary
• Vegetation can reduce soil erosion
• There are no “Cook Book Recipes”-Site-specific planning is required
• List and explain components
• Plan for the entire year
• Plan for maintenance
109
Questions ?
