652.03 Construction Requirement s.
GROUND PREPARATION, VEGETATION ESTABLISHMENT AND MOWING
652.01 Description.
This Section shall cover ground preparation work and the work of establishing an acceptable permanent stand of vegetation of the species designated for establishment. This section also covers mowing of vegetated areas.
652.02 Materials.
Materials (seed mixes, mulch, fertilizer, etc.) shall be furnished in compliance with the requirements given in Section 860.
652.03 Construction Requirements.
a.Construction Sequence . The required sequ ence and timing of the placement of permanent seeding during excavation and embankment construction is given in Suba rticle 210.03(a). The Engineer may direct, even to the exclusion of other operations, that the Contractor promptly complete grading and grou nd preparation to allow the establishment of permanent vegetation in areas where it is necessary for the control of erosion and sediment.
b.Seed Mixes for the Establishment of Permanent Vegetation . The appropriate seed mix shall be chosen from tables in Section 860. The appropriate seed mix is based on planting zone, planting date, and type of area to be seeded. Seed mixes of a temporary nature are required in some areas of the State when permanent seed mixes are out of season. These mixes are shown in S ection 860 as requiring seeding in stubble for the establishment of the required permanent plant.
c.Inspection . The Contractor shall notify the Project Manager at least 48 hours in advance of any work related to seeding. This includes the mixing of se ed as well as the sowing of seed. The Contractor shall notify the Engineer of the proposed type of seed mix or mixes to be incorporated into the project prior to beginning seeding operations. Seeding work shall not begin prior to the measurement of the area to be seeded. All work shall be performed in the presence of the Engineer.
d.Preparation and Planting in Soft Soil .
1.Ground Preparation . After grading and topsoil placement and prior to ground preparation, the Contractor shall remove all boulders, stumps, roots, or other objects with any dimension larger than 2 inches {50 mm}. Topsoil shall meet the requirements given in Section 650. Ground preparation shall consist of cultivating the topsoil to a loose depth of at least 4 inches {100 mm} except on slopes 2:1 or steeper. The plowing, harrowing, cultivating, and all other operations shall be performed with proper equipment and in such a manner as to break up all clods. The ground shall be plow ed to the required depth and then cultivated with a rotary tiller or disk harrow, in crossing directions if necessary, until the result is a smooth, uniform, loose, and well broken soil providing a suitable bed for seed. In small or inaccessible areas the use of hand tools will be permitted. The Contractor shall add water as necessary to provide sufficient soil moisture to prepare the ground. All trash and other debris shall be removed from the cultivated topsoil. All pieces of wood, rocks and unbroken clumps of earth with any dimension larger than 2 inches {50 mm} shall be removed from the planting area.
2.Initial Soil Amendments . The initial fertilization shall be a commercial fertilizer that will provide at least 120 pounds {135 kg} of N, 120 pounds {135 kg} of P 2O5, and 120 pounds {135 kg} of K 2O per acre {hectare}, as computed from the nominal contents of fertilizer elements. Only one half of this rate shall be applied when the required seeding is Annual Ryegrass. Agricultural limestone (lime) shall be applied prior to
652.03 Construction Requirements.
seeding at a rate of two tons per acre {4.5 metric tons per hectare}. Lime may be applied in dry, pelletized or slurry form. The rate of application is required regardless of the form of application. The required rates of placement of fertilizer and lime may increase as directed by the Engineer based on the results of the testing of the Topsoil from Stockpiles as described in Article 650.02. Additional fertilizer and lime for Topsoil from Stockpiles will be paid for separately in accordance with the requirements given in Article 652.05. Reductions in rates will result in a price adjustment for seeding. Fertilizers and agricultural limestone (lime) shall be applied uniformly at the required rates of placement. The fertilizer shall be wel l pulverized and free of lumps when applied. In no case shall fertilizer that is not mixed with soil be permitted to be in direct contact with seed. When fertilizers are applied hydraulically they shall be diluted sufficiently so that no damage is done to either seed or established vegetation. Agricultural limestone, basic slag or a combination of limestone and slag shall be applied separately but may be incorporated into the soil with fertilizers in one operation. Fertilizer and agricultural limestone tha t is not applied hydraulically shall be uniformly mixed with the soil by harrows, rotary tillers, or other soil mixing equipment prior to subsequent operations. Mixing with the soil will not be required when the fertilizer and agricultural limestone is a pplied hydraulically.
3.Sowing Seed . Mechanical or hydraulic seeders shall be used for sowing unless approved otherwise by the Engineer. Sowing shall not be performed during windy weather, when the prepared surface is crusted, or when the ground is fro zen, wet or otherwise in a non -tillable condition. The addition of water may be required to render excessively dry soils tillable. Equipment for applying seed hydraulically shall be designed for this purpose. The equipment shall be capable of mixing and pu mping the water, seed mixture, mulch and fertilizer uniformly over the area to be seeded. Power driven agitators shall be provided to keep the mixture uniform during the application.
4.Covering Seed . Care shall be exercised during covering operations to preserve the line, grade and cross -section of the seeded areas so that areas adjacent to pavement, walks, etc., are not left higher than the paved surface. The seed bed shall be compacted immediately after sowing. Compaction shall be done with a cultipacke r, light roller or approved drag. The weight {mass} of the roller or drag needed shall be determined by the Contractor according to the type and physical condition of the soil. Rolling or covering of seed may be omitted when both seeding and mulching are h ydraulically applied.
5.Mulching . Mulching shall be applied in accordance with the requirements given in Section 656. Seeded areas shall be covered with mulch within 48 hours after seeding. Mulching will be measured and paid for separately under Section 656.
6.Soil Amendments After Growth . After the required plant species have emerged and shown normal growth (usually approximately 40 days) and while the soil surface is moist, a second application of fertilizer shall be made. This second application sha ll be placed as a uniformly applied top dressing of 40 pounds {45kg} each of N, P 2O5, and K 2O per acre {hectare}, respectively or equivalent approved by the Engineer. This application of fertilizer will not be required for temporary planting (Annual Ryegra ss).
e.Preparation and Planting in Rocky or Hardpan Areas.
1.Conditions for Planting in Rocky Areas . The requirements for planting in rocky or hardpan areas shall apply when the Engineer determines that the area is too rocky or compacted for plowing, di sking, and harrowing, but is sufficiently soft or shaley to permit some form of treatment
2.Initial Soil Amendments. One half of the fertilizer and all of the lime required for the initial fertilization of soft soil shall be applied before the initial s carification.
3.Initial Scarification . The fertilizer and lime shall be worked into the rocky or hardpan area by an initial scarification as directed by the Engineer.
652.03 Construction Requirements.
4.Coverage with Topsoil . Approximately 4 inches {100 mm} of topsoil shall be placed over the scarified and fertilized rocky or hardpan area.
5.Soil Amendments after Placement of Topsoil . The second half of the fertilizer required for the initial fertilization of soft soil shall be applied after the placement of the topsoil.
6.Sowing, Covering, Mulching and Fertilizing after Growth . The sowing of the seeds, covering of the seeds, mulching, and fertilization after growth of the seeds shall be in accordance with the requirements given for this work in soft soil.
f.Preparation and Planting on Steep Slopes (2H:1V or Steeper ).
1.Ground Preparation . Planting operations may proceed without further ground preparation after topsoil spreading and tracking if the planting c an be accomplished within 72 hours after the tracking operations. Tracking is the mechanical roughening of the slope surface. Tracking shall be accomplished by the movement upslope and downslope (not along the slope) of heavy equipment that operates on tra cks.
2.Initial Soil Amendments . One half of the fertilizer and all of the lime required for the initial fertilization of soft soil shall be applied hydraulically.
3.Sowing . The sowing of seeds shall be in accordance with the requirements given for t his work in soft soil with the exception that hydraulic seed application is required.
4.Mulching . Mulching shall be applied in accordance with the requirements given in Section 656. Seeded areas shall be covered with mulch within 48 hours after seeding. Mulching will be measured and paid for separately in accordance with the requirements given in Section 656.
5.Second Application of Fertilizer after Mulching . Half of the fertilizer required for the initial fertilization of soft soil shall be applied hy draulically approximately 40 calendar days after mulching.
6.Third Application of Fertilizer . A third application of fertilizer shall be made approximately 40 calendar days after the second application of fertilizer. This application shall be placed hy draulically as a uniformly applied top dressing of 500 pounds {560 kg} of 8- 8-8 fertilizer per acre {hectare} or equivalent approved by the Engineer.
g.Seeding in Stubble . The seeding in stubble method of planting shall be used to establish permanent species when initial vegetation establishment occurs during a season that is not optimal for the permanent planting. Dates for seeding in stubble are designated in the seed mix tables in Section 860. This method requires that the existing vegetation be mowed to a height of approximately 3 inches {75 mm} or sprayed with an approved herbicide, or both, to retard further growth. The area shall then be lightly scarified by disking or other approved method to p repare a suitable seedbed. The initial fertilization, sowing of the seeds, covering of the seeds, and fertilization after growth of the seeds shall be in accordance with the requirements given for this work in soft soil. Additional agricultural lime appli cation will not be required for seeding in stubble. Mulch may be applied to bare areas if requested by the Contractor and approved by the Engineer. Mulch shall be furnished and paid for in accordance with the requirements given in Section 656.
h.Establi shment and Acceptance . All work shall be conducted in accordance with the requirements given in Section 665 as well as the requirements given in this Section. The Contractor shall provide plant establishment of the required species of permanent vegetation prior to final acceptance of the project. Plant establishment shall consist of preserving, protecting, reseeding, or replanting and other such work and at such time as may be necessary to keep the vegetated areas in a satisfactory condition. All of the above work shall be performed without additional compensation, unless otherwise specified. The acceptance of designated seeded areas will be based upon verification of a satisfactory stand of vegetative cover in the season for each species required for establishment. If a satisfactory stand of
652.04 Method of Measurement.
desired vegetation is not established, the area shall be re- seeded after appropriate soil preparation and re -established without additional cost to the Department. A satisfactory stand of vegetative cover shall be defined as a cover of living plants, after true leaves are formed, of the required seed species designated for establishment. Generally an 8 5 % coverage will be considered acceptable. Should the Contractor protest the determination of satisfactory stand based on visual analysis, a random sampling of 5 samples per acre {0.4 ha} using a square yard {meter} template may be executed to determine the percent coverage. There should be no areas void of the required species larger than 4 square feet {0.4 square meter}. Payment for seeding, fertilizer, and agricultural limestone and mulch will be made in full upon satisfactory application. Payment for additional fertilizer and agricultural limestone will be made in ac cordance with the requirements given in Article 652.05. Payment for seeding may be withdrawn for areas where vegetative cover is not established or not satisfactorily maintained and fertilized after establishment. Every effort should be made to establish v egetation of permanent species in accordance with the seasonal requirements shown for each species in Section 860. Areas where the season and required seed mix cause the method of seeding in stubble to be necessary for the establishment of a permanent plant will not be considered acceptable until vegetation of a permanent species is satisfactorily established. The project will not be accepted for maintenance prior to acceptable establishment of vegetation after seeding in stubble. Payment will not be m ade for areas of unsatisfactory stands of vegetative cover, the repair of areas damaged by the Contractor, or for the repair of washes in areas where sufficient erosion control measures are available to the Contractor. Requests from the Contractor for paym ent for areas of unsatisfactory stands of vegetative cover will not be considered by the Construction Engineer without the submittal of documentation of absolute adherence to the requirements for the application of topsoil and for the establishment of the vegetation.
i.Mowing . The Contractor shall mow all seeded areas of medians, shoulders and front slopes as directed or permitted by the Engineer. The Contractor shall mow when the vegetation becomes a hazard to motorists and as necessary to promote growth of the required permanent plant. Mowing shall be performed in a manner that will not cause unnecessary damage to desirable vegetation. Mowing of lespedezas and tall fescue shall not be done until after these plants have produced mature seed. Mowing shall generally be done twice each year as directed or permitted by the Engineer and when vegetation has grown to a height of 16 inches. If the project is being considered for acceptance for maintenance by the Department and has been mowed within the last 2 mont hs, additional mowing will not be required. The Contractor shall mow, cut and trim as close as practicable to all fixed objects, exercising extreme care not to damage trees, plants, shrubs, delineators and other appurtenances. Damage to trees, plants, shr ubs, delineators or other appurtenances shall be repaired or replaced immediately by the Contractor at no cost to the Department. The Engineer will determine if the damage must be corrected by repair or replacement.
652.04 Method of Measurement.
a.Seedin g. Seeding will be measured in acres {hectares} parallel to the seeded surface regardless of the method of establishment.
b.Mowing . Mowing will be measured in acres {hectares} parallel to the mowed surface. Each separate mowing of the same location will be measured separately.
652.05 Basis of Payment.
a.Unit Price Coverage . Seeding will be paid for at the contract unit price per acre {hectare} which shall be full compensation for all ground preparation, furnishing, preparing, soil amendments (ferti lizer and lime), seeds, including water needed in mixing, planting, establishing, and maintaining of the seeded areas until final acceptance, and for all materials, equipment, tools, labor, and incidentals necessary to complete the work. Additional fertili zer or agricultural limestone ordered by the Engineer will be paid at the verified invoice price plus 15 percent. The seeding item will be used for payment for establishing
654.05 Basis of Payment.
vegetation regardless of the methods used for planting and establishment. Vegetatio n established outside of the normal planting season (annual ryegrass) will be paid for at the contract price for seeding. Vegetation established by seeding in stubble will also be paid for at the contract unit price for seeding. All mowing, cutting and tr imming, including mowing required for seeding in stubble will be paid for at the contract unit price bid per acre {hectare} which shall be payment in full for the mowing including equipment, labor, and incidentals necessary to complete this item of work. The contract unit price shall also be for mowing required when the vegetation becomes a hazard to motorists and as necessary to promote growth of the required permanent vegetation.
b.Payment will be made under Item No .: 652-A Seeding - per acre {hectare } 652-C Mowing - per acre {hectare} SECTION 654 SOLID SODDING
654.01 Description.
This Section shall cover the work of furnishing solid grass sodding in designated locations throughout the construction limits of the work. Basic work consists of ground preparation, furnishing and placing required soil amendments, and furnishing and inst alling sod and maintenance of the sod including watering of the sod for the life of the contract.
654.02 Materials.
All materials shall conform to the requirements of Article 860.05. A list of acceptable mulch control netting products (LIST II -20, “TACKIFIERS, MULCH CONTROL NETTING, AND HYDRAULIC MULCH PRODUCTS”) is given in the ALDOT manual titled “Materials, Sources, and Devices with Special Acceptance Requirements”.
654.03 Construction Requirements.
Areas to receive sod shall be prepared in accordance with the requirements for planting vegetation in soft soil given in Section 652. The requirements for ground preparation and the application of initial and final amendments to the soil shall apply to this work. The sod shall be placed on the prepared and amended soil with no gaps between the individual sod pieces or rolls . The entire sodded area shall be rolled with a weighted roller to set each piece of sod into the topsoil. Staking or stapling of sod is required on slopes 3:1 or steeper and all chan nel applications and shall be done without additional compensation. When required by the plans, mulch control netting shall be applied in accordance with Section 656 and shall be a subsidiary obligation . The Contractor shall water, fill washes, and otherwise protect and maintain all sodded areas until the contract is accepted for maintenance or until the bond is released if a bond was required. Payment will not be made for areas of unsatisfactory stands of vegetative cover, the repair of areas damaged by the Contractor, or for the repair of washes in areas where sufficient erosion control measures are available to the Contractor. Requests from the Contractor for payment for areas of unsatisfactory sod will not be considered without the submittal of documen tation of absolute adherence to the requirements for the establishment of the solid sodding. The requirements given in Section 652 shall apply to the determination of a satisfactory installation of solid sod except that a 95 % living coverage will be requi red.
654.04 Method of Measurement.
Solid Sodding will be measured in square yards {square meters} from measurements made parallel to the surface of the area covered by the sod.
654.05 Basis of Payment.
a.Unit Price Coverage . Solid Sodding will be paid fo r at the contract unit price, which price shall be full compensation for furnishing the sod, ground preparation, planting, soil amendments, rolling, watering, and maintaining the sod until acceptance of the contract, and for all other materials, equipment, tools, and labor
Source: Alabama Standard Specifications for Highway Construction, 2022 Edition. Pages 548–551 of 934.