Section 2601. Erosion Control.

2601.01 DESCRIPTION.
Erosion control shall consist of seeding and fertilizing; overseeding and fertilizing; stabilizing crop seeding and fertilizing; sodding; special ditch control with wood excelsior mat, jute mesh, or other specified material; special ditch control over sod; slope protection with the specified material; fertilizing; fertilizing for stabilizing crop seeding; mulching for control of surface drainage; and removal of temporary water pollution control measures in accordance with Section 2602, on areas within and adjacent to the right-of-way in accordance with the contract documents and the following provisions.

2601.02 MATERIALS.
The Contractor shall furnish material meeting the requirements of Section 4169.

The Contractor shall be responsible for applying all materials at not less than the minimum rate specified in the contract documents. Application rates of seeds for native grasses shall be on a Pure Live Seed (PLS) basis, as computed by the Engineer. For native grasses identified in Article 4169.02 with both purity and germination requirements, application rates for grasses that exceed these minimum requirements shall be adjusted to an equivalent computed on a Pure Live Seed basis. Additional compensation will not be allowed for materials in excess of that specified, unless directed by the Engineer. If, after application of the fertilizer, it is determined by test that the fertilizer fails to comply with minimum requirements, the Contractor shall furnish and apply additional fertilizer to comply with minimum requirements as defined in Article 4169.03.

Work shall be performed in a manner that will provide the Engineer the opportunity to verify the quantity of material furnished and the rate of application. The project area shall be divided into small natural areas that are to be constructed as identifiable units, and the Contractor shall furnish a tally of the quantities of each material as it is used on each area. This may include weights (mass) from approved scales of truck loads of bulk materials, other scaled weights (mass), counts of containers, bags, or bales, or estimates of partially used packages of materials, as approved by the Engineer. Details of this requirement shall be such as to provide the Engineer the opportunity to verify the quality and quantities and to result in a continuous operation with minimum delays.

When handling inoculants, and sticking agents, the Contractor shall follow safety precautions as specified on the product label.

2601.03 EQUIPMENT.
Equipment shall meet requirements of Section 2001 and the following, except that other equipment which will produce similar results will be considered for approval.

Methods and procedures shall be consistent with equipment manufacturers' recommendations, however, ground driven equipment shall not be operated at speeds greater than 10 mph (15 km/h).

A. Disk.
When preparing a seedbed on ground having heavy vegetation, a disk having cutaway blades shall be used. Provisions shall be made for the addition of weight (mass) in order to obtain proper cutting depth.

B. Slope Harrow.
A slope harrow shall consist of a rolling weight (mass) attached by heavy chain to a tractor. The chain shall be of suitable length, shall have picks attached, and shall have a means of rotating the picks as the rolling weight (mass) is pulled in a direction parallel to the movement of the tractor.

C. Field Tiller.
The equipment used shall be designed for the preparation of the seedbed to the degree specified.

D. Rotary Tiller.
Equipment shall have rotary type blades designed for the preparation of seedbed to the degree specified.

E. Spike Tooth Harrow.
The equipment shall be designed to provide adjustment of the spike teeth to level the ground or to be used as specified by the Engineer.

F. Compaction Equipment.

1. Cultipacker.
A pull type cultipacker shall have individual rollers or wheels. Cultipackers having sprocket type spacers between the wheels may be used. The cultipacker shall produce a corrugated surface on the area being compacted. Operation of the cultipacker shall be separate from all other operations, and attachment of the cultipacker to the seeder or disk shall not be permitted, except when the combined cultipacker seeder is manufactured to operate as a unit. Provisions shall be made for addition of weight (mass).

2. Compaction Rollers.
Article 2001.05, A shall apply.

3. Hand Tamping Equipment.
Hand tamping equipment shall be the base plate type adapted to the performance of the work and subject to approval of the Engineer.

4. Expanded Mesh Roller.
The equipment shall be of the open grid type or the cultipacker type modified by covering with expanded metal mesh.

G. Hydraulic Seeder.
Hydraulic seeding equipment shall include a pump rated at not less than 100 gallons (350 L) per minute. Inoculant, seed, and fertilizer may be applied in a single operation, unless otherwise stated in the contract documents. The equipment shall have a suitable working pressure and a nozzle adapted to the type of work. Supply tanks shall have a means of agitation. Tanks shall be calibrated and provided with a calibration stick or other approved device to indicate the volume used or remaining in the tank.

H. Gravity Seeders.
Gravity seeders shall provide agitation of the seed, have an adjustable gate opening, and shall uniformly distribute seed on the prepared seedbed. The seed hopper shall be equipped with baffle plates spaced not more than 2 feet (0.6 m) apart. The baffle plates shall extend from the agitator shaft to within approximately 2 inches (50 mm) of the top of the seed hopper. Wind guards will be required to facilitate seeding when moderate wind conditions exist and when ordered by the Engineer. Wind guards shall be placed in front or in back (or both) of the seed outlet and shall extend to near the ground line.

This seeder may be used for application of fertilizer.

I. Endgate Cyclone Seeders.
Endgate cyclone seeders shall be suitably mounted. Movement shall be provided by mechanical means. The seed shall drop through an adjustable flow regulator onto a rotating, power driven, horizontal disk or fan.

J. Hand Cyclone Seeders.
Hand cyclone seeders shall be carried by the person dispensing seed. The seed shall drop through an adjustable flow regulator onto a rotating, hand driven, horizontal disk or fan.

K. Native Grass Seed Drill.
The native grass seed drill shall be designed to provide uniform distribution of native grass and wildflower seeds. Separate seed boxes shall be provided to apply both small seeds as well as fluffy bearded seeds. If a no till attachment is specified, the attachment shall be of the same manufacturer as the drill.

L. Aerial Equipment.
When aerial application of seed and fertilizer is specified, the aerial equipment shall be capable of providing a uniform distribution of seed and fertilizer on the specified area.

M. Straw Mulching Machine.
The machine shall be a type that will uniformly apply mulch material over the desired area without excessive pulverization. The Engineer may consider excessive pulverization as the general absence of straw longer than 6 inches (150 mm) after distribution.

N. Mulch Stabilizer.
A mulch stabilizer shall be designed to anchor straw or hay mulch into soil by means of dull blades or disks. The blades or disks shall be flat, may have cutaway edges, shall have a nominal minimum diameter of 20 inches (500 mm), and shall be spaced at approximately 8 inches (200 mm) intervals. The mulch stabilizer shall be pulled by mechanical means and shall weigh (have a mass of) approximately 1,000 pounds (450 kg). When directed by the Engineer, the weight (mass) shall be increased by addition of ballast.

O. Mechanical Trencher.
The equipment used shall be a machine designed for the specific purpose of constructing a trench for placement of check slots to the depth specified.

P. Mowers.
Mowers shall be of the rotary, flail, disk, or sickle type. They shall not bunch or windrow mowed material.

2601.04 SEEDING.
Seeding shall include the operations of seedbed preparation, furnishing, sowing, and covering the seed, and compaction of the seedbed on various portions of the right-of-way, except on the traveled portion of the roadbed. Seeding, shall also include such other areas as may be indicated in the contract documents or directed by the Engineer. The limits of areas to be seeded will be clearly marked before the seedbed is prepared.

All areas having a satisfactory growth of desirable grasses or legumes shall not be disturbed.

Seed shall be sown only at times of the year when temperature, moisture, and climatic conditions will promote germination and plant growth. Normal permanent seed application dates are between March 1 and May 31 and between August 10 and September 30. The seeding shall be in accordance with the following procedures:

A. Seedbed Preparation.
The area to be seeded shall be relatively smooth, and all washes and gullies shall be filled to conform to the desired cross section. When such fills exceed 6 inches (150 mm), the material shall be compacted with a tractor wheel or other suitable field equipment. Preparation of all ditches designated for special ditch control shall be coordinated with the seedbed preparation.

Areas accessible to field machinery shall be thoroughly worked to a depth of not less than 3 inches (75 mm). Mechanical rotary tillage equipment shall be used for the preparation of seedbed on earth shoulders, urban or raised medians, rest areas, and islands. Areas inaccessible to field machinery shall be prepared by hand to a depth of not less than 2 inches (50 mm). Care shall be used that the entire width of the shoulder and areas around headwalls, wingwalls, flumes, and other structures are prepared in the manner specified. Where weed growth has developed extensively, they may be disked into the ground. If weed growth develops sufficiently to interfere with proper seedbed preparation, the Contractor shall mow the weeds and remove them from the project at the Contractor's expense.

Crawler type or dual wheeled tractors shall be used for seedbed preparation. Equipment shall be operated in a manner to minimize displacement of soil and disturbance of the design cross section. Ridging in excess of 4 inches (100 mm) due to operation of tillage equipment shall be harrowed prior to rolling with the cultipacker. The area shall be rolled with not less than one pass of the cultipacker prior to permanent seeding.

Ruts that develop during the sequence of operations shall be removed before subsequent operations are performed.

After seedbed preparation has been completed, the Contractor shall pick up and remove all debris in accordance with Article 1104.08, including 3 inch (75 mm) diameter or larger stones, logs, stumps, cable, or other objectionable material that will interfere with the seeding operation.

B. Application of Fertilizer.
Fertilizer shall be spread over the areas at the rate designated. When not otherwise specified in the contract documents, the rate to be used shall be 750 pounds per acre (840 kg/ha) of 13-13-13 (or equivalent) commercial fertilizer. All fertilizer shall be spread with a mechanical spreader which will secure a uniform rate of application. Truck mounted spreading equipment for bulk fertilizer will not be permitted. On areas accessible to field machinery, fertilizer shall be spread after the preliminary preparation of seedbed, but prior to the sowing of any seed. The fertilizer shall be disked in and the area rolled prior to the application of permanent seed. If the roller cannot be operated satisfactorily, substitution of the harrow may be permitted by the Engineer. On areas inaccessible to field machinery, fertilizer shall be spread after preparation of the seedbed and shall be thoroughly raked into the soil.

Application of fertilizer in combination with seeding by a hydraulic seeder shall be as specified in Article 2601.04, H. When the contract documents require two applications of fertilizer, the second application shall be during the next permanent seeding period following initial seeding and application of fertilizer.

C. Application of Seed.
The following seed mixture shall be used for permanent seeding of rural areas, unless otherwise specified in the contract documents:

Fescue, Fawn
Ryegrass (Perennial)
Sideoats Grama (Butte or Trailway)

Switchgrass (Neb. 28, Blackwell,
Pathfinder, or Cave-In-Rock)
Birdsfoot Trefoil (Empire)		 25 lbs. per acre (28 kg/ha)
15 lbs. per acre (17 kg/ha)
5 lbs. PLS per acre (6 kg PLS/ha)


3 lbs. PLS per acre (3 kg PLS/ha)
5 lbs. per acre (5 kg/ha)

The following seed mixture shall be used for permanent seeding of urban areas, including any areas previously maintained as a lawn. The application rate shall be 4 pounds per 1,000 square feet (2 kg per 100 m2.)

Bluegrass, Kentucky
Ryegrass, Perennial (Fineleaf variety)
Fescue, Creeping Red		 70%
10%
20%
A commercial mixture may be used if it contains high percentage of similar bluegrasses; it may contain Creeping Red Fescue.

D. Application of Special Seed.
When not shown in the contract documents but directed by the Engineer, a special seed or seed mixture may be required in addition to the regular seed mixture. This seed shall be applied, at the rate ordered, as a separate operation, either immediately before or immediately after sowing the regular grass mixture. No additional work other than sowing of the seed will be required. On limited areas, this seed may be applied by hand cyclone seeders.

E. Preparation of Seed.
Except when a hydraulic seeder is used, all seed specified for the contract shall be thoroughly mixed prior to placing the seed in the seed hopper. All seed mixing shall be witnessed by the Engineer. The Contractor shall provide 48 hour notice to the Engineer prior to mixing the seed.

All legumes shall be inoculated with a standard culture at the rate as specified by the manufacturer of the inoculant in accordance with Article 4169.04. The inoculant shall be a type specified for each legume seed and approved by the Engineer. Inoculated seed shall not be exposed to direct sunlight for more than 30 minutes. Seed that is not sown within 8 hours after inoculation shall be reinoculated prior to use. Preinoculated seed with manufacturer's recommended protective coating may be used in lieu of seed with Contractor applied inoculant.

When the gravity or cyclone seeder is used for application of seed, inoculation of legume seed shall be in accordance with the manufacturer's recommended procedures, before mixing with other grass seeds for sowing. If the hydraulic seeder is used, inoculant, in quantities specified above, may be applied directly into the supply tank with seed, water, and other material. Inoculant shall be furnished and applied by the Contractor.

All seed shall be treated with a commercial sticking agent to be applied prior to application of inoculant, or as a mixture when the sticking agent is compatible with other materials, except with hydraulic equipment. A sticking agent is not required if a liquid formulation of inoculant is used.

Mechanical mixing equipment shall be used for application of the sticking agent and inoculant on seed quantities over 50 pounds (25 kg) per batch.

F. Sowing Grasses and Legumes.
On all areas accessible to field machinery, all grass and legume seed may be sown with a gravity, cyclone, or hydraulic seeder, a native grass seed drill, or aerial equipment or as specified in the contract documents. On areas inaccessible to field machinery, use of hand cyclone seeders will be permitted. Sowing of grass and legume seed must be performed as a split rate application (not less than two passes).

Hairy vetch may be seeded until September 30. All other legume and native grass seed shall not be seeded after August 31, but the work shall be deferred until spring. The spring seeding of legume and native grass seed may be performed in one operation, with a cyclone seeder, hydraulic seeder, or aerial equipment when the ground is friable from frost action. Covering, compaction, rolling, dragging, or raking of the seedbed will not be required provided the friable condition exists. For spring seeding (following fall seedbed preparation) after April 1, the Contractor will be required to roll or harrow when, in the opinion of the Engineer, a friable condition does not exist.

Crownvetch seed shall be applied only in the spring or as designated in the contract documents.

The crownvetch seeding required shall be considered the final operation of seeding, fertilizing, and mulching for erosion control projects under construction during the spring seeding period.

G. Covering and Compaction of Grasses and Legumes.
Sowing of the grasses and legumes shall be followed by not less than one complete rolling with the cultipacker. Shoulders shall be rolled immediately to prevent loss of seed due to air currents created by passing traffic.

Where the compaction equipment will not operate satisfactorily, the seeded area shall be lightly dragged or raked in by hand. The seedbed shall be rolled with a cultipacker before as well as after seeding.

H. Seeding and Fertilizing with Hydraulic Seeder.
The Contractor may use a hydraulic seeder only when the seedbed has been prepared in accordance with Paragraph A of this article. When a hydraulic seeder is used, the Contractor shall apply all seed or fertilizer, or both, at the rates specified in approximately 400 gallons (4000 L) of water slurry per acre (hectare).

After fertilizer and seed are placed in the hydraulic seeder, the mixture shall be applied within 1 hour. Continuous agitation will be required. Seed remaining in the fertilizer solution for more than 1 hour will be unacceptable, and additional seed at the specified contract rate will be required.

I. Fall Seeding.
The normal fall seeding period shall be August 10 through September 30. Crownvetch seed shall be applied only in the spring seeding period or as designated in the contract documents. Seeding after August 31 shall consist of stabilizing crop seed, hairy vetch (legume seed), and grass seed except native grass. All other legume seed and native grass seed shall be sown the following spring as soon as possible after March 1, and before April 1, when the ground is friable from frost action, as directed by the Engineer and according to Paragraph F.

J. Urban Seeding.
The fertilizer shall be applied prior to the preparation of seedbed.

A rotary tiller will be required for the preparation of seedbed in accordance with Paragraph A. The seedbed shall be firm, smooth, and reasonably free of any material 1 1/2 inches (40 mm) in diameter or greater including clods, rocks, and other debris prior to the application of seed. The seedbed shall be rolled both before and after the application of seed. Equipment for rolling shall be of the open grid type, or of the cultipacker type modified by covering with expanded metal mesh.

Areas inaccessible to field equipment shall be prepared, rolled, seeded, and fertilized with hand or hand operated equipment, including lawn type, hand cyclone, or gravity equipment. Such equipment shall be subject to approval of the Engineer.

K. Spring Overseeding.
Seedbed preparation will not be required, provided the overseeding is applied when the ground is friable from frost action after February 1 and before April 1 or as directed by the Engineer. For overseeding, when in the opinion of the Engineer a friable soil condition does not exist, the Contractor will be required to roll with a cultipacker or harrow. Sowing of grass legume seed mixture shall be performed as a split rate application (not less than two passes).

L. Native Grass Seeding and Wetland Grass Seeding.
The following seed mixture shall be used, unless otherwise specified in the contract documents, for areas designated for native grass seeding or wetland grass seeding between April 1 and June 30 and between August 1 and August 31.

SEEDS
COMMON NAMES, SCIENTIFIC NAMES, PLS
Common Name Scientific Name PLS
(per ac)		 PLS
(per ha)
NATIVE GRASSES:

Annual Ryegrass
Canada Wild Rye
Switchgrass - Blackwell, NE, 28, Pathfinder, or Cave-in-Rock
Big Bluestem - Kaw, Roundtree, or Champ
Indiangrass - NE, 54, Otto, or Holt
Little Bluestem - Blaze, Aldous, or Camper
Sideoats Grama - Butte, or Trailway
Blue Grama
Purple Prairieclover
Blackeyed Susan
Prairie Blazing Star
Purple Coneflower
Plains Coreopsis
Grayhead Prairie
New England Aster

Lolium perenne, var. italicum
Elymus canadensis
Panicum virgatum
Andropogon gerardi
Sorghastrum nutans
Andropogon scoparius
Bouteloua curtipendula
Bouteloua gracilis
Petalostemum purpureum
Rudbeckia hirta
Liatris pycnostachya
Echinacea purpurea
Coreopsis tinctoria
Ratibida pinnata
Aster novac-angliae

45 lbs.
12 lbs.
2 lbs.
8 lbs.
8 lbs.
4 lbs.
3 lbs.
3 lbs.
4 oz.
4 oz.
4 oz.
4 oz.
4 oz.
4 oz.
2 oz.

50 kg
13 kg
2.2 kg
9 kg
9 kg
4.5 kg
3.4 kg
3.4 kg
280 g
280 g
280 g
280 g
280 g
280 g
140 g

SEEDS
COMMON NAMES, SCIENTIFIC NAMES, PLS
Common Name Scientific Name PLS
lbs. per ac		 PLS
kg per ha
WETLAND GRASSES:      
Blue vervain Verbena hastata 0.31 0.35
Boneset Eupatorium perfoliatum 0.25 0.28
Nodding bur marigold Bidens cernua 0.31 0.35
Swamp milkweed Asclepias incarnata 0.50 0.56
Sneezeweed Helenium autumnale 0.44 0.49
Water plantain Alisma plantago-aquatica 1.00 1.12
Arrowhead Sagittaria latifolia 0.50 0.56
New England aster Aster novae-angliae 0.50 0.56
Big Bluestem Andropogon gerardii 2.00 2.24
Switchgrass Panicum virgatum 1.00 1.12
Barnyard grass Echinochloa crus-galli 1.00 1.12
Bluejoint grass Calamagrostis canadensis 1.00 1.12
Rice cutgrass Leersia oryzoides 1.00 1.12
Dark Green bulrush Scirpus atrovirens 0.50 0.56
Fox sedge Carex vulpinoidea 0.50 0.56
Softstem bulrush Schoenoplectus tabernaemontani 0.69 0.77
Spike rush Eleocharis palustris 0.50 0.56
Seeding rate (PLS)   12.00 lbs./ac 13.44 kg/ha

Seed shall be uniformly applied to areas with the seedbed prepared as in Article 2601.04, A. Areas accessible to field equipment shall be seeded with a native grass seed drill, gravity, or broadcast equipment and shall be cultipacked as specified in Paragraph G of this article. Other areas shall be broadcast seeded followed by a light dragging or hand raking.

In areas with existing stabilized crop residue, seed shall be applied with a native grass seed drill with a no till attachment. Seedbed preparation and cultipacking will not be required.

Seeding shall be performed as a split rate application (not less than two passes.)

M. Wildflower Seeding.
When specified in the contract documents, the designated wildflower seed mix shall be applied between April 15 and June 30 and between August 1 and August 31. Seed shall be uniformly applied to areas with the seedbed prepared as in Article 2601.04, A. Areas accessible to field equipment shall be seeded with a native grass seed drill at an approximate depth of 1/8 inch (3 mm), gravity, or broadcast equipment and shall be cultipacked as specified in Paragraph A. Other areas shall be broadcast seeded following by a light dragging or hand raking.

In areas with existing stabilized crop seeding residue, seed shall be applied with a native grass seed drill with a no till attachment. Seedbed preparation and cultipacking will not be required.

Wildflower seeding shall be performed as a split application (not less than two passes).

N. Mowing.
Mowing may be required prior to permanent seeding and any time during the growing season following permanent seeding. The Contractor will be notified by the Engineer to begin each mowing. The Contractor will be charged working days, beginning with the third working day after notification to start mowing, until each mowing is complete.

The Contractor shall use suitable equipment for mowing. Bunching or windrowing of mowed vegetation will not be permitted. Hand equipment will be required for areas inaccessible to other equipment. The cutting height shall be approximately 6 inches (150 mm). Not less than two mowing units shall be in operation to facilitate the work. More than one pass may be required for each mowing.

2601.05 STABILIZING CROP SEEDING AND FERTILIZING.
The seedbed shall be prepared in accordance with Article 2601.04, A.

A. Stabilizing Crop Seed Mixture.
Stabilizing crop seed mixture to be used shall be in accordance with the following rates and schedule unless otherwise specified in the contract documents.

Stabilizing crop seeding shall be applied utilizing full seedbed preparation and incorporation.

Overseeding of stabilizing crop seeding will only be allowed on areas which are not accessible to field equipment.

Spring -- March 1 to May 20
Oat
Winter Rye
Red Clover
Timothy		 2 bu. per acre (75 kg/ha)
1 bu. per acre (63 kg/ha)
5 lbs. per acre (6 kg/ha)
5 lbs. per acre (6 kg/ha)
Summer -- May 21 to July 20
Oat
Annual Rye
Red Clover
Timothy		 3 bu. per acre (108 kg/ha)
35 lbs. per acre (39 kg/ha)
5 lbs. per acre (6 kg/ha)
5 lbs. per acre (6 kg/ha)
Fall -- July 21 to September 30
Oat
Winter Rye
Red Clover
Timothy		 2 bu. per acre (72 kg/ha)
2 bu. per acre (126 kg/ha)
5 lbs. per acre (6 kg/ha)
5 lbs. per acre (6 kg/ha)

All legume specified for stabilizing crop seed shall be treated with inoculant prior to mixing with the remainder of the seed mixture.

B. Fertilizing for Stabilizing Crop Seeding.
A commercial fertilizer shall be applied to all seeded areas at the rate of 450 pounds per acre (500 kg/ha) of 13-13-13 (or equivalent) unless otherwise specified in the contract documents.

The provisions of Article 2601.04, B shall apply.

C. Covering and Compaction of Stabilizing Crop Seeding.
The covering of stabilized crop seed and fertilizer shall be accomplished with a light disking or with other tillage equipment such as a rigid harrow, spring tooth harrow, or field cultivator. Following this tillage, the area shall be rolled with a cultipacker. If the cultipacker cannot be operated satisfactorily, substitution of the harrow may be permitted by the Engineer.

2601.06 MULCHING.
All seeding areas shall be mulched unless otherwise designated in the contract documents.

A. Time of Mulching.
All areas requiring mulch shall be mulched as soon as seed is sown and final rolling completed.

B. Application of Mulch.
Mulch shall be evenly and uniformly distributed and anchored into the soil. The application rate for reasonably dry material shall be approximately 1 1/2 tons per acre (3.5 Mg/ha) of dry cereal straw, 2 tons per acre (4.5 Mg/ha) of wood excelsior, or 2 tons per acre (4.5 Mg/ha) of prairie hay, or other approved material, depending on the type of material furnished. All accessible mulched areas shall have mulch consolidated into the soil with a mulch stabilizer, and slope areas shall be tucked on the contour. Crawler type or dual wheel tractors shall be used for the mulching operation. Equipment shall be operated in a manner to minimize displacement of the soil and disturbance of the design cross section.

2601.07 RESEEDING, REFERTILIZING, AND REMULCHING.
When all work related to seeding on an area has been completed, but is washed out or damaged prior to final acceptance of the project by the Engineer, and that area involves seeding in combination with mulching or fertilizing or both, the area shall be reseeded, refertilized, and remulched at the contract unit prices when ordered by the Engineer.

Fertilized or seeded areas damaged by rain prior to required mulching shall be refertilized or reseeded or both at a rate not to exceed the specified rate, as designated by the Engineer. This work shall be at no additional cost to the Contracting Authority.

2601.08 SODDING.
Areas to be sodded shall be shown in the contract documents or designated by the Engineer. Prior to shaping the sodbed, the Engineer will define upon the ground the limits of areas to be sodded, and indicate the center lines of waterways. The Contractor shall cover the designated areas with live sod, meeting requirements of Article 4169.07, closely placed and properly fitted against structures and adjacent sod, in accordance with the following provisions:

A. Preparation of Sodbed.
The Contractor shall shape and prepare all surfaces to be sodded. Areas to be sodded shall be firm and even surfaces, free of any material 1 1/2 inches (40 mm) in diameter or greater including clods, rocks, and other debris. All ditch channels, slopes, and flumes to be sodded shall have a typical cross section as shown in the contract documents.

The ditch channel shall be constructed to secure a relatively level, flat bottom ditch cross section with a minimum depth of 6 inches (150 mm), measured from the finished sodbed ground line at the edge of the ditch. Scarifying prior to shaping may be necessary to assure the minimum depth. A minimum sod ditch overall width of 7 1/2 feet (2.2 m) (sloping sides) will be required.

The Contractor shall use a soil compaction roller in accordance with Article 2601.03, for compaction and reshaping of ditches. The layers of fill materials shall not be more than 8 inches (200 mm) in depth.

After the surface of the layer has been smoothed and before material for the next layer is deposited upon it, the layer shall be compacted with not less than one passage of a soil compaction roller per inch (25 mm) of loose thickness of the layer and until the roller is supported entirely on its tamping feet. The roller will be considered to be supported entirely on its tamping feet when the tamping feet penetrate not more than 3 inches (75 mm) into an 8 inch (200 mm) layer being compacted. A single section roller may be necessary for this operation in some locations. The compacted area shall extend approximately 6 inches to 12 inches (150 mm to 300 mm) beyond the width of the ditch. After compaction, the ditch shall be shaped.

B. Fertilizer for Sod.
Two applications are required (initial and prior to final acceptance). After sodbed preparation and prior to placing sod, the area to be sodded and the adjacent disturbed area shall be fertilized at a rate of 10 pounds per 1,000 square feet (5 kg per 100 m2) using a commercial fertilizer specified for the project. The final application of fertilizer shall be made at a rate of 10 pounds per 1,000 square feet within 5 calendar days of the end of the 30 calendar day watering period and prior to final acceptance of the project. The final application shall be made when the grass is dry and with a dry form of fertilizer. In either case, if the type of fertilizer is not specified, 13-13-13 (or equivalent) commercial fertilizer shall be applied. Fertilizer shall be spread with a mechanical spreader which will secure a uniform rate of application. Manipulation or mixing with the soil, other than that incidental to Paragraph D of this article, will not be required.

C. Placing Sod.
Sod shall not be placed between the dates of May 31 and August 10, or on frozen ground unless otherwise directed by the Engineer.

Sod shall be carefully placed in rows or strips. On slopes, the strips shall be transverse to the flow of water over the area. On the sides and bottoms of ditches and channels, the strips shall be at right angles to the center line of the channel. Sod strips shall be placed tightly against each other so that no open joints are apparent.

Joints at the ends of sod strips shall be staggered at least 1 foot (0.3 m) on adjacent rows or strips of sod. Sod to be placed in road ditch channels, intercepting ditches, or sod flumes where the total sodded width is less than 7 1/2 feet( 2.2 m) shall be cut into strips having lengths equal to the width of the sodded area. At the top of slope or at the edge of channel, sod shall be laid so that water from adjacent areas will have free flow onto the sodded area. Sodding in road ditch channels and flumes shall begin at the outlet or lower end and progress upward. On slopes, sodding shall begin at the bottom and progress upward. If necessary to protect sod already laid, the Contractor shall furnish ladders or planks for use of workers, without extra compensation.

The Engineer may order the staking of sod flumes, slopes, and ditch channels to minimize erosion loss before establishment. Staking of sod shall be done as shown in the contract documents and as required by the Engineer.

D. Finishing Sod.
Soil shall be firmed along the edge of the sodded area. The adjacent disturbed area shall be properly shaped and smoothed to allow surface water to flow into the sod ditch. Excessive soil placed over the edge of the sod will not be permitted.

All rural disturbed areas adjacent to the sod shall have the seedbed prepared, seeded, and seed raked in. The disturbed area shall be seeded with the following seed mixture at the rate of 2 pounds per 1,000 square feet (1 kg per 100 m2).

Fescue, Fawn
Ryegrass, Perennial		 80%
20%

The seed mixture adjacent to sod for urban projects shall be that specified for the project. The disturbed area shall be mulched with grass, hay, or straw at the rate of 70 pounds per 1,000 square feet (35 kg per 100 m2).

The sod, sodbed, and all disturbed areas shall then be watered in accordance with Paragraph E of this article.

When sod ditches are constructed after October 1, the grasses shall be overseeded the following spring when weather and soil conditions are favorable between March 1 and April 1.

When initial watering of the sod does not secure adequate bond between the sod and soil, the Engineer may require rolling. If sod is allowed to be placed between May 31 and August 10 and it is not to be staked, it shall be rolled with equipment approved by the Engineer. Sod rejected from a sod ditch shall be removed from the project. Any other material not otherwise incorporated into the work shall be removed from the site.

In urban areas, islands, and rest areas, the sod shall be rolled prior to or following the initial watering, with a hand operated, lawn type roller approved by the Engineer.

E. Watering Sod.
The Contractor shall provide watering equipment and an approved water supply before any sodding operation is begun. Six waterings will be required. Not more than 1 hour shall elapse between laying and initial watering of sod. The second, third, and fourth waterings shall be at 4 calendar day intervals, and the fifth and sixth waterings shall be at weekly intervals, at the discretion of the Engineer and subject to local weather conditions.

All waterings shall be sufficient to saturate thoroughly the sod, sodbed, and adjacent disturbed areas to a depth of approximately 4 inches (100 mm). Each watering may require a maximum of 100 gallons of water per square (40 L of water per square meter), and the water shall be applied as a spray or dispersion to prevent damage to the sod. Each watering shall be completed within a 4 hour period, and more than one application for each watering may be necessary to provide adequate saturation without runoff.

F. Urban, Island, and Safety Rest Area Sodding.
Areas to be sodded, except ditch channels, shall be prepared in accordance with Article 2601.04, J. During the total watering period, the sod shall be mowed once to a 3 inch (75 mm) height approximately 3 weeks after placement.

2601.09 CONSTRUCTING AND RESHAPING INTERCEPTING DITCHES AND FLUMES.
When the slope of adjacent land is toward the backslope of road excavations and the extent of the area drained will result in sufficient water flowing over the backslope to cause serious erosion, ditches shall be constructed to intercept the flow of surface water and conduct it into proper drainage channels, as provided in Article 2102.08. These intercepting ditches and flumes shall conform to the typical cross section shown in the contract documents.

The ditch shall be formed by excavating or blading earth from the area on the downhill side of the ditch location. This material shall be deposited in a windrow and compacted to form the ditch and provide the bank for the downhill side.

For reshaping of intercepting ditches, the earth excavated from the ditch shall be compacted to the bank on the lower side of the ditch.

2601.10 SPECIAL DITCH CONTROL AND SLOPE PROTECTION.
This work shall include the following:

A. Special ditch control wood excelsior mat or other material specified shall include shaping of channels on all ditches, furnishing and applying seed and fertilizer, mulch, ditch control material, and water, all in accordance with the contract documents.

B. Special ditch control over sod shall include furnishing and applying jute mesh or other specified material, including staples, over the sodded areas.

C. Slope protection wood excelsior mat or other material specified shall include furnishing and applying of the specified material on the slopes designated by the Engineer.

The Engineer will designate the areas for each type of work.

2601.11 PREPARATION OF AREA TO BE TREATED WITH SPECIAL DITCH CONTROL AND SLOPE PROTECTION.
The ditch channel shall be shaped in the same manner as preparing a ditch for sod as provided in Article 2601.08, A.

During ditch shaping operations, a seedbed shall be provided with a friable soil condition on the surface. Slope areas to be protected with ditch control material shall be prepared as preparing a seedbed for seeding as provided in Article 2601.04, A, except the depth shall be not less than 3/4 inch (20 mm).

All material 1 1/2 inches (40 mm) in diameter or greater, including clods, rocks, and other debris, which will prevent contact of the ditch control material with the seedbed, shall be removed.

Preparation of the ditches for special ditch control and placement of the ditch control material shall be coordinated with the seedbed preparation, seeding, including sticking agent, and inoculant, fertilizing, and mulching of the adjacent area of right-of-way.

Areas to be protected with slope protection materials shall be prepared as preparing a seedbed for seeding, as provided in Article 2601.04, A.

2601.12 SEEDING FOR SPECIAL DITCH CONTROL AND SLOPE PROTECTION.
Seed shall be sown prior to placement of ditch control material, unless otherwise directed by the Engineer. Seed shall be treated with sticking agent, inoculant.

A. Special Ditch Control in Depressed Medians and Other Ditch Areas.
Ditches and depressed medians shall be seeded at a rate of 5 pounds per 1,000 square feet (2.5 kg per 100 m2) as directed by the Engineer, using the following seed mixture:

Fescue, or Fawn
Birdsfoot Trefoil (Empire)
Ryegrass, Perennial		 70%
10%
20%

B. Slope Protection and Urban Seeding Areas.
The seed mixture shall be as specified for the project.

2601.13 FERTILIZER FOR SPECIAL DITCH CONTROL AND SLOPE PROTECTION.
After the area is prepared and prior to laying the specified material, the ditch channel shall be fertilized at the rate of 10 pounds per 1,000 square feet (5 kg per 100 m2) using the commercial fertilizer specified for the project.

If the type of fertilizer is not specified for the project, 10 pounds per 1,000 square feet (5 kg per 100 m2) of 13-13-13 (or equivalent) commercial fertilizer shall be applied. The fertilizer shall be spread with a mechanical spreader, which will secure a uniform rate of application. Manipulation or mixing with the soil other than that incidental to Article 2601.17 will not be required.

Fertilizer for slope protection shall be as specified for the project.

2601.14 MULCH FOR SPECIAL DITCH CONTROL AND SLOPE PROTECTION.
Mulch shall be placed as follows:

A. Special Ditch Control.
Prior to placement of the specified ditch control material, mulch shall be placed. The application rate shall be 25 pounds per 1,000 square feet (12 kg per 100 m2). Mulch will not be required for special ditch control (wood excelsior mat).

B. Slope Protection.
The method of mulch installation for slope protection shall be as shown in the contract documents. The application rate for mulch shall be as specified in Article 2601.06, B. Mulch will not be required for slope protection (wood excelsior mat).

2601.15 APPLICATION OF SPECIAL DITCH CONTROL MATERIALS ON SEEDED AREAS.
The areas of special ditch control will be designated by the Engineer. The ditch channel shall be shaped as provided in Article 2601.08, A. The provisions of Articles 2601.12, 2601.13, 2601.17, and 2601.19 shall apply. See the contract documents for details for installation of the material.

A. Wood Excelsior Mat.
Check slots on ditch channels must be spaced so that one check slot occurs within each 50 foot (15 m) increment on slopes of more than 4%.

Wood excelsior mat shall be applied without tension and in the direction of the flow of water. Where more than one strip is required, the lap joint shall be lapped not less than 3 inches (75 mm). The anchor slot on the top edge of the wood excelsior mat shall be buried from 6 inches to 12 inches (150 mm to 300 mm), as designated by the Engineer.

On junction slots, the upslope end of each strip of wood excelsior mat shall be buried 6 inches (150 mm), with the soil firmly tamped. Ends of the wood excelsior mat shall overlap at least 12 inches (300 mm) and shall be stapled, with the upgrade section on top.

The terminal fold at the bottom end of the wood excelsior mat shall be stapled.

Wire staples shall be driven without objectionable bending. The staples shall be No. 11 gauge (3.06 mm diameter) wire, meeting the requirements of Article 4169.10, B. Staples shall be spaced as shown in the contract documents.

B. Jute Mesh.
Before fertilizer, seed, mulch, and jute mesh are applied to the area specified, all check slots shall be installed. They shall be installed at right angles to the direction of water flow, using jute mesh approximately 48 inches (1.3 m) wide, by placing a tight fold from 6 inches to 12 inches (150 mm to 300 mm) vertically into the soil, as designated by the Engineer. The jute mesh shall be tamped and stapled into place.

Check slots on ditch channels shall be spaced so that one check slot occurs within each 50 foot (15 m) increment on slopes of 4% or less. On slopes of more than 4 %, there shall be one check slot and additional check slots, as determined by the Engineer, so that there is a check slot in each increment of 25 feet (7.5 m) or less.

Jute mesh shall be applied without tension and in the direction of the flow of water. When more than one strip is required, the lap joint shall be lapped not less than 3 inches (75 mm).

The anchor slot on the top edge of the jute mesh shall be buried from 6 inches to 12 inches (150 mm to 300 mm), as designated by the Engineer.

On junction slots, the upslope end of each strip of jute mesh shall be buried 6 inches to 12 inches (150 mm to 300 mm), as designated by the Engineer, with the soil firmly tamped. Ends of the jute mesh shall overlap at least 12 inches (300 mm) with the end folded under approximately 4 inches (100 mm) and stapled, with the upgrade section on top. Rolls of jute mesh containing splices that are not securely sewn by machine shall be separated and junction slots installed.

The terminal fold at the bottom end of the jute mesh shall be folded under approximately 4 inches and stapled.

For all anchor slots, junction slots, check slots, and terminal folds, suitable U-shaped staples shall be used. Wire staples shall be driven without objectionable bending. The staples shall be No. 11 gauge (3.06 mm diameter) wire meeting the requirements of Article 4169.10, B. For some soil conditions, No. 13 gauge (2.32 mm diameter) wire staples meeting the requirements of Article 4169.10, B will be accepted. Staples shall be spaced as shown in the contract documents.

C. Other Materials.
When other materials are specified, the details for installation will be specified in the contract documents.

2601.16 SPECIAL DITCH CONTROL OVER SOD.
When shown in the contract documents, the Contractor shall place jute mesh, plastic netting, or other approved material over sod and staple it in place. Staples shall be spaced 3 feet (1 m) apart in the row, and rows shall be not more than 2 feet (0.6 m) apart. Staples shall be placed alternately to adjacent rows. There will be no junction slots or check slots required. Anchor slots and terminal folds will be required.

2601.17 FINISHING ADJACENT TO SPECIAL DITCH CONTROL AREAS.
Adjacent areas disturbed outside of ditch channels shall be uniformly shaped, fertilized, seeded, and seed raked in, as required for disturbed areas adjacent to sod ditches, except the seed used shall be as specified in Article 2601.12. This work shall be completed during the normal permanent seeding period or by the date specified to complete seeding.

2601.18 APPLICATION OF SLOPE CONTROL MATERIALS OVER SEEDED AREAS.
The details for applying slope control materials over seeded areas will be shown in the contract documents.

2601.19 WATERING OF SPECIAL DITCH CONTROL AND SLOPE PROTECTION.
The Contractor shall provide watering equipment and an approved water supply before special ditch control or slope protection work is started. Following placement of the materials as specified, the area shall be watered not later than the day following placement. Three additional waterings shall be applied at approximately 1 week intervals at the discretion of the Engineer and subject to local weather conditions.

All waterings shall be sufficient to saturate thoroughly the seedbed to a depth of approximately 3 inches (75 mm). Each watering may require a maximum of 100 gallons of water per square (40 L of water per square meter), and the water shall be applied as a spray or dispersion to prevent damage to the seedbed. Each watering shall be completed within a 4 hour period, and more than one application for each watering may be necessary to provide adequate saturation without runoff.

2601.20 COMPLETION OF THE WORK.
Priority shall be given to medians, islands, interchange quadrants, urban areas, and rest areas, including the area between rest areas and the highway. Work shall be scheduled so that all work, except sodding, in these areas is completed first, except as authorized by the Engineer.

All phases of this work, except sodding, shall be coordinated and completed so that the Contractor's operation for any phase of work will not extend more than 2 miles (3 km) from portions already completed, except with permission of the Engineer. All phases of this work, excluding the 30 calendar day maintenance of sodded areas, shall be completed within the specified construction schedule.

When any work included in the contract is washed out or damaged prior to final acceptance of the project, the Engineer may order replacement of the damaged portion and will advise the Contractor of the approximate quantity of replacement required. The Contractor shall make these repairs during the normal permanent seeding period and shall be responsible for satisfactory maintenance of the work in a manner satisfactory to the Engineer.

Should the Contractor fail to make this replacement when directed by the Engineer, or to perform necessary maintenance to the area, replacement in addition to the quantity directed by the Engineer to complete the work in an acceptable condition shall be the responsibility of the Contractor.

2601.21 METHOD OF MEASUREMENT.
The various items of work involving erosion control will be determined on satisfactory completion as follows:

The Engineer will compute in acres to the nearest 0.1 acre (hectares to the nearest 0.1 hectare) the surface areas of Overseeding and Fertilizing, Seeding and Fertilizing, Mulching, Native Grass Seeding, Wetland Grass Seeding, Wildflower Seeding, Stabilizing Crop Seeding and Fertilizing, Seeding Special Areas, and Crownvetch Seeding.

The Engineer will measure in squares of 100 square feet (square meters to the nearest 0.1 m) the surface areas of Sodding.

Debris picked up and removed, in accordance with Article 2601.04, A, will be measured in cubic yards (cubic meters) by cross sectional measurement or in the hauling units, at the option of the Engineer.

The Engineer will measure the area of Special Ditch Control and Slope Protection in squares of 100 square feet (square meters to the nearest 0.1 m). Measurement of actual area covered will be used, but will not exceed an area based on the actual measured length and design width. Materials used for anchor slots, junction slots, check slots, terminal folds, lap joints, mulch, and seed and fertilizer for Special Ditch Control shall be incidental.

Watering will be measured for payment by counting loads from a transporting tank of known volume or by metering.

Mobilization for watering will be paid for by count for each mobilization. Mobilization for the initial watering required at installation of the plant material will not be measured for payment.

Mowing described in Article 2601.04, N, will be measured in acres to the nearest 0.1 acre (hectares to the nearest 0.1 hectare) of surface area.

2601.22 BASIS OF PAYMENT.
Payment will be made for the various items of work involved in erosion control as follows:

For the number of acres to the nearest 0.1 acre (hectares to the nearest 0.1 hectare) of Overseeding and Fertilizing, Seeding and Fertilizing, Native Grass Seeding, Wetland Grass Seeding, Wildflower Seeding, Stabilizing Crop Seeding and Fertilizing, and Crownvetch Seeding, the Contractor will be paid the contract unit price per acre (hectare). This payment shall be full compensation for preparing the area and furnishing and applying each material.

For the number of acres to the nearest 0.1 acre (hectares to the nearest 0.1 hectare) of Seeding Special Area, the Contractor will be paid the contract unit price per acre (hectare). This payment shall be full compensation for preparing the area and furnishing and applying the seed and fertilizer as specified.

For sowing special seed ordered by the Engineer but not provided for in the contract documents, the Contractor will be paid the delivered cost of the seed plus 10% of the contract unit price for Seeding and Fertilizing.

For the number of squares (square meters) of Sodding, the Contractor will be paid the contract unit price per square (square meter). This payment shall be full compensation for preparing the sodbed, furnishing, placing, and finishing the sod, and fertilizing. This payment shall also be compensation for repair of adjacent areas disturbed by the sodding operation.

For the number of squares (square meters) of staking of sod flumes, slopes, and ditch channels, the Contractor will be paid 25% of the contract unit price for Sodding in addition to payment for Sodding.

For the quantity of mulch furnished and placed, the Contractor will be paid the predetermined contract unit price per acre (hectare).

Debris pickup for grading work shall be in accordance with Article 2102.03. Debris pickup of additional boulders resulting from Stabilized Crop Seeding and Fertilizing will be paid for as described in Article 2102.14 for Class 12 boulders, or if there is no Class 12 item, the Contractor will be paid at the rate of 10 times the contract unit price for Class 10 excavation. For the number of cubic yards (cubic meters) of debris picked up and removed in conjunction with other work, the Contractor will be paid 25% of the contract unit price for Stabilizing Crop Seeding or Seeding and Fertilizing, as applicable.

For the number of squares (square meters) of Special Ditch Control over Sod, Wood Excelsior Mat or other material, as specified, the Contractor will be paid the contract unit price per square (square meter). This payment shall be full compensation for the special ditch control preparation and materials, including reshaping intercepting ditches and flumes, seed, fertilizer, stapling, mulch, and in areas where special ditch control is specified, for construction of intercepting ditches and flumes.

For the number of squares (square meters) of Slope Protection with Wood Excelsior Mat or other material, as specified, the Contractor will be paid the contract unit price per square (square meter). This payment shall be full compensation for the slope protection materials in addition to the amount paid for seed and fertilizer.

When a large area is to be watered, the contract documents will include an item for watering. For the quantity of water applied to sod, Article 2601.08, E, and to special ditch control and slope protection, Article 2601.19, the Contractor will be paid the contract unit price per 1,000 gallons (kiloliter). When an item for watering is not included, the cost of watering shall be included in the amount paid for the item to be watered.

Mobilization for watering will be paid for by count for each required watering at the pre-determined price of $350.00 each.

For the number of acres to the nearest 0.1 acre (hectares to the nearest 0.1 hectare) of mowing, as described in Article 2601.04, the Contractor will be paid the contract unit price per acre (hectare).

Payment for these items shall be full compensation for furnishing all materials, equipment, tools, and labor necessary to complete the work according to the contract documents. It includes removal of rock and other debris from the area, filling gullies and washes, preparing the seedbed or sodbed, furnishing and placing sod and staking sod, furnishing and placing seed including any treatment required, furnishing and placing fertilizer and mulch, tucking the mulched areas, furnishing and placing wood excelsior mat or jute mesh, and furnishing water and other care during the care period.

Payment will not be allowed for any area seeded until all seeding of the area permitted by the season is completed, including crown vetch seeding in the spring, and until the Special Ditch Control, Slope Protection, fertilizer and mulch are placed.

Payment will not be allowed for the Special Ditch Control and Sod until the watering, as specified, has been completed. Special Ditch Control and Sod areas which are damaged by weather or other causes before the specified initial watering has been completed shall be replaced or repaired, at the discretion of the Engineer, at the Contractor's expense.

Areas of completed work which are damaged by weather or other causes during the care period and which are repaired at the direction of the Engineer will be paid for at the contract unit prices for the respective types of work involved. Should the repair work not be done with reasonable promptness, payment for repair will be limited to the work described at the time of notification.

Furnishing of extra length stakes or staples when directed by the Engineer will be paid for as extra work in accordance with Article 1109.03, B.

When suitable soil for filling holes, gullies, or washes is not available adjacent to the area to be filled or when soil must be removed, necessary loading and hauling directed by the Engineer will be paid for as extra work in accordance with Article 1109.03, B.