Attachment 3 - Section 07000 - Landscape Specifications.pdf

Revised 05/02/09

13 NOV 08

SECTION 07000

LANDSCAPE SPECIFICATIONS

PART 1 GENERAL

1.1 DESCRIPTION OF WORK

• The extent of vegetation planting is indicated on the drawings.

• Types of work required include the following:

• Furnishing trees, shrubs, and groundcover.

• Submitting soil samples for laboratory for analysis.

• Preparation of planting pits and planting area soil preparation including excavation, backfilling and disposal of surplus and unsuitable excavated material.

• Planting work shall consist of planting plants, amending the soil, applying sulfur and mulch and staking plants as specified in this specification and the Statement of Work.

• Maintenance until final acceptance by the Government.

• Related work specified in other specifications. Irrigation System and Turf

Planting. If irrigation is to be installed by the Contractor, the irrigation system must be fully operational prior to commencement of landscape and tree operations.

1.2 QUALITY ASSURANCE

1.2.1 Comply with all applicable local, state and federal requirements regarding materials, methods of work, and disposal of excess and waste materials.

1.2.2 All trees shall be true to name as ordered or shown on the planting plans and shall be labeled individually or in groups by species and cultivar (where appropriate).

1.2.3 Trees shall be free of pests (insects, pathogens, nematodes or other injurious organisms); where formal arrangements of consecutive order of trees are shown, select stock for uniform height and spread.

1.2.4 No plant substitution shall be permitted without written consent from the

Government. If required landscape material is not obtainable, submit proof of non-availability to the Government, together with a written proposal for use of an equivalent plant material. At the time bids are submitted, the Contractor is assumed to have located the materials necessary to complete the job as specified.

1.2.5 The Contractor shall guarantee all plants for one (1) year from the date of written acceptance by the Government. Guarantee Definition: At any and all time throughout the one (1) year warranty period all dead or dying plants and all those determined not to be in a normal, vigorous growing condition are to be replaced with similar size and exact same species of plant at no expense to the Government within ten (10) calendar days of receipt of written or email notification. The Contractor is not responsible for unusual phenomena or incidents which are beyond the Contractor’s control.

1.3 QUALITY CONTROL: An inspection of the crown, trunk, and roots shall find the following characteristics:

1.3.1 Crown Form:

The form or shape of the crown is typical for a young specimen of the species/cultivar. The crown is not significantly deformed by wind, pruning practices, pests or other factors.

1.3.2 Leaves:

The size, color and appearance of leaves are typical for the time of year and stage of growth of the species/cultivar. Leaves are not stunted, misshapen, tattered, discolored (chlorotic or necrotic) or otherwise atypical.

1.3.3 Trees shall have a single, relatively straight central leader and tapered trunk, free of co-dominant stems and vigorous, upright braches that compete with the central leader. See Exhibit A.

1.3.4 Branches:

Shoot growth (length and diameter) throughout the crown is typical for the age/size of the species/cultivar. Trees do not have dead, diseased, broken, distorted or other serious branch injuries.

1.3.5 Main Branches: Branches should be distributed radially around and vertically along the trunk, forming a generally symmetrical crown typical for the species.

• Main Branches, for the most part shall be well spaced. See Exhibit B.

• Branch diameter shall be no greater than two thirds (2/3) the diameter of the trunk, measured one inch (1”) above the branch. See Exhibit C.

• The attachment of scaffold branches shall be free of included bark. See Exhibit

D.

• Trunk: The trunk should be fairly straight, vertical and free of wounds (except properly –made pruning cuts), sunburned areas, conks (fungal fruiting bodies), wood cracks, bleeding areas, signs of boring insects, galls, cankers/lesions and girdling ties.

• Tree height and trunk diameter are typical for the age, species/cultivar and container size.

• Roots: The root system is free of injury from biotic (insects, pathogens, etc.) and abiotic agents (herbicide toxicity, salt injury, excess irrigations, etc.). Root distribution is uniform throughout the soil mix or growth media and growth is typical for the species/cultivar.

Exhibit A.

Acceptable tree leader

Unacceptable tree leader

Exhibit B.

Exhibit C.

acceptable unacceptable acceptable unacceptable

Exhibit D.

acceptable unacceptable acceptable unacceptable

Exhibit E

One gallon plants Top row is preferred - Bottom row is unacceptable

1.4 TRUNK

1.4.1 Trunk diameter and taper shall be sufficient so that the tree will remain vertical without the support of a nursery stake.

1.4.2 Trunk diameter at six inches (6”) above the soil shall be within the diameter range shown for each container size below:

Container Size Trunk Diameter (inches)

# 5 (gallon) …………………….. 0.5” to 0.75”

# 15 (gallon) …………………... 0.75” to 1.5”

24 inch box …………………....... 1.5” to 2.5”

1.5 ROOTS

1.5.1 The trunk, root collar (root crown) and large roots shall be free of circling and/or kinked roots. Soil removal near the root collar may be necessary to inspect for circling and/or kinked roots.

Preferable unacceptable

1.5.2 The tree shall be well rooted in the soil mix. When the container is removed, the root-ball shall remain intact. When the trunk is carefully lifted both the trunk and root system shall move as one.

1.5.3 The upper—most roots or root collar shall be within one inch (1”) above or below the soil surface.

1.5.4 The root-ball periphery should be free of large circling and bottom matted roots.

The acceptable diameter of circling peripheral roots depends on species and size of root-ball. The maximum acceptable size should be indicated for the species (if necessary).

One gallon plants Unacceptable Preferred

1.6 MOISTURE STATUS

At the time of inspection and delivery, the root ball shall be moist throughout.

The crown shall show no signs of moisture stress as indicated by wilted, shriveled or dead leaves or branch dieback. The roots shall show no sign of excess soil moisture conditions as indicated by poor root growth, root discoloration, distortion, death or foul odor.

1.7 MEASUREMENTS

Measure trees with branches and trunks or canes in their normal position. Do not prune to obtain required sizes. Take caliper measurements six inches (6”) above ground for trees up to and including four inch (4”) caliper size, and twelve inches (12”) above ground for larger sizes. Measure main body of all plant material of height and spread dimensions, do not measure from branch or root tip-to-tip.

1.8 INSPECTION

The Government’s Representative may choose to inspect plants either at place of growth or at site before planting for compliance with requirements for genus, species, variety, size, and quality. The Government retains right to further inspect plants for size and condition of balls and defective root systems, insects, injuries, and latent defects, and to reject unsatisfactory or defective, materials at any time during progress of work. Remove rejected plant materials immediately from project site and replace with acceptable material as no additional cost to the Government.

1.9 DEFINITIONS

Acid soil -- A soil with a pH lower than 7.0 is an acid soil.

Aerate -- Loosening or puncturing the soil to increase water penetration.

Allelopathy -- An anti-competition mechanism of some (particularly scrub and chaparral) plants, whereby chemicals are released into the environment that inhibit germination or growth of other plants.

Alkaline soil -- A soil with a pH higher than 7.0 is an alkaline soil.

Ball and Burlap -- refers to the root-ball which has been dug up, while "burlapped" refers to the wrapping material traditionally used for transporting tree and shrub deliveries.

Botanical name -- The Latin or “scientific” name of a plant, usually composed of two words, the genus and the species.

Clay -- Composed of plate-like particles 0.0002 to 0.002 millimeters in diameter. Due to very tiny flat particles, clay soil feels greasy when rubbed between the fingers. Clay soil drains exceedingly slowly.

Co-dominant -- Two or more vigorous and upright branches of relatively equal size that originate from a common point, usually where the leader has been lost or removed Crown -- The aboveground part of the tree including the trunk.

Crown rot -- Fungal disease infecting tissues in woody plants where the stem meets the roots.

Cultivar -- A named plant selection from which identical or nearly identical plants can be produced, usually by vegetative propagation or cloning.

Cultivate -- Process of breaking up the soil surface, removing weeds, and preparing for planting.

Drip line -- The circle which would exist if you drew a line below the tips of the outer most branches of a tree or plant.

Endemic -- Plants native to California that grow nowhere else.

Erosion -- The wearing away, washing away, or removal of soil by wind, water or man.

Germinate --When a seed, spore or other structure begins or resumes growth.

Girdling root -- A root that partially or entirely encircles the trunk and/or buttress roots, which could restrict growth and downward movement of photosynthate and/or water and nutrients.

Green waste compost -- A 'restricted' material under organic standards, which means that an organic producer needs to get approval from Soil Association Certification Ltd (SA Certification) before they can use green waste materials on organic land and crops.

Included bark -- Bark embedded within the crotch between a branch and the trunk or between two or more stems that prevents the formation of a normal branch bark ridge.

Kinked root -- A primary root(s), which is sharply bent, causing a restriction to water, nutrient, and photosynthate movement. Kinked roots may compromise the structural stability of roots systems.

Leader -- The dominant stem which usually develops into the main trunk.

Mulch -- A loose layer either natural or man-made, composed of organic or mineral materials, placed on top of soil near plants for weed and plant predator suppression, for insulation against heat or cold near roots of plants, and to conserve water in dry areas.

Native plant -- A plant that evolved in response to the environmental conditions here.

pH -- A set of numbers running from 1 to 14. pH numbers represent the negative logarithm to base 10 of hydrogen ion activity. The pH of pure water is 7. Acid soil has a pH lower than 7. Alkaline soil has a pH higher than 7.

Photosynthate -- Pertains to sugar and other carbohydrates that are produced by the foliage during photosynthesis, an energy trapping process.

Root collar -- The flared area at the base of a tree where the roots and trunk merge.

Also referred to as the “root crown” or “root flare”.

Scaffold branches -- Large, main branches that form the main structure of the tree.

Trunk -- The main stem or axis of a tree that is supported and nourished by the roots and to which branches are attached.

1.10 ACRONYMS

AF Air Force AGG aggregate ASTM American Society for Testing Materials B&B ball and burlap BLDG building BMP best management practices CAL caliper CONC concrete CNPS California Native Plant Society CESA California Endangered Species Act CF cubic feet CY cubic yard DBH diameter at breast height DIA diameter EA each ELEC electrical ESA Endangered Species Act EST estimate EXT existing FF finished floor GA gauge GAL gallon GALV galvanized HT height LED light emitting diode LF linear feet LOW Limit of Work Metropolitan Metropolitan Water District of Southern California MSDS Material Safety Data Sheet N North NEPA National Environmental Policy Act OC on center OSHA Occupational Safety and Health Administration PVC polyvinyl chloride REQ’D required SCH schedule SPEC specifications TYP typical USDA United States Department of Agricultural UV ultra violet

1.11 CLEARING AND GRUBBING

1.11.1 This work shall consist of removing objectionable material from within areas to be excavated and other areas as may be specified. Clearing and grubbing shall be performed in advance of grading operations and in accordance with the requirements specified in these specifications.

1.11.2 Within the limits of clearing, the areas below the natural ground surface shall be grubbed to a depth necessary to remove all stumps, roots, buried logs, and all other objectionable material.

1.11.3 Trees and plants that are not to be removed shall be protected from injury or damage resulting from the Contractor’s operations at the Contractor’s expense.

Only trees and plants that are designated or marked for removal by the Engineer shall be removed.

1.11.4 Trees shall be felled in such a manner as not to injure standing trees, plants and improvements which are to be preserved.

1.11.5 Materials removed shall be disposed properly outside the Los Angeles Air Force

Base.

1.11.6 The contract lump sum price paid for clearing and grubbing shall include full compensation for furnishing all labor, materials, tools, equipment, and incidentals, and for doing all work involved in clearing and grubbing as shown on the plans, and as specified in these specifications and as directed by the Engineer, including the removal and disposal of the resulting material. , during the pre-construction conference, the details of their environmental compliance program for their activities on LAAFB properties.

1.12 SUBMITTALS: The Contractor shall provide the following submittal to

61 CELS/CEPM through the Contracting Officer for approval, prior to the start of any activities on LAAFB.

• Product Certification: Submit certificates of inspections as may be required by governing authorities to accompany shipments. For standard products, submit manufacturer’s certified analysis. For other materials, submit analysis by a recognized laboratory made in accordance with methods established by Association of Official Agricultural Chemist.

• Planting Schedule: Submit proposed planting schedule indicating anticipated dates and locations for each type planting.

• Material Sources:

- Submit to the Government, a list of all plant materials and their source.

- Submit to the Government a sample of all soil amendment materials and their source.

- Submit to the Government a sample of all mulch materials, to include wood chips, tree bark, rock, and glass, and their source.

This list shall be submitted no later than five (5) days after Notice to Proceed.

• Submit the Material Safety Data Sheet (MSDS) for any and all chemicals to be used on the job site prior their use.

• Maintenance Instructions: Submit typewritten instructions recommending procedures to be established by the Government for maintenance of landscape work during entire year. Submit prior to final inspection for Government acceptance of landscape work

• As the project progresses, additional submittals may be required. These will be identified, before construction begins, with anticipated submittal dates.

A photograph of the required submittal material is unacceptable. Wood chips, tree bark, and soil amendments sample shall be submitted in a properly labeled quart size plastic bag. All rock and glass mulches shall be submitted in a properly labeled gallon container.

The Contractor shall submit proof from three nurseries specializes in growing California Native plants before any plants substitutions will be considered. All substitutions shall have the same PH, USDA, height, width and rainfall range. It shall also fulfill the same purpose in the landscape and the original plant choice.

PART 2 MATERIALS

2.1 SOIL AMENDMENT

Soil amendment shall be green waste, also known as yard waste compost that has been aged oxidized. The green waste compost shall not contain bio solids, cow or dairy products. The green waste or yard waste compost has be approximately half inch (1/2”) to three-quarters (3/4”) of an inch in size

2.2 COMMERCIAL FERTILIZER

2.2.1 Commercial fertilizer shall conform to the requirements of the California Food and Agricultural Code.

2.2.2 Commercial fertilizer for turf planting work shall be in granular form and shall have the chemical analysis specified in the Statement of Work.

2.2.3 Commercial fertilizer shall not be used in the planting work of California Native plants.

2.3 TOP SOIL

Top soil shall consist of fertile, friable soil of loamy character, and shall contain an amount of organic matter normal to the region. It shall be obtained from well-drained arable land and shall be free of subsoil, refuse, roots, heavy or stiff clay, stones larger than one inch in size, coarse sand, noxious seeds, sticks, brush, litter and other deleterious substances. Top soil shall be capable of sustaining healthy plant (turf) life.

2.4 SULFUR

Commercial sulfur shall be Elemental Sulfur, (99% sulfur material).

2.5 MULCH

1. Unless otherwise specified in the Statement of Work or shown on the plans, mulch shall consist of wood chips or tree bark or any combination thereof, at the Government’s option.

2. Mulch materials produced from pine trees grown in Alameda, Monterey, Santa

Clara, Santa Cruz, San Luis Obispo or San Mateo Counties shall not be used.

3. Wood chips shall be manufactured from clean wood. The particle size of the chips shall be between half inch (½ “) and three inches (3”) in length, and not less than three-eights inch (3/8”) in width and one-sixteenth inch (1/16”) in thickness.

4. At least ninety percent (90%), by volume, of wood chips shall conform to the sizes specified.

5. Wood chips produced from tree trimmings which contain leaves or small twigs will not be accepted.

6. Tree bark shall have a particle size between one inch (1”) and two inches (2”) and shall be free of salt and foreign materials such as clods, coarse objects, sticks, rocks, weeds or weed seeds.

7. Shredded bark shall be a mixture of shredded bark and wood; shall have a particle size between one-eighth inch (1/8”) and one and a half inches (1-1/2”) in thickness and one inch (1”) to eight inches (8”) in length; and shall be free of salt and deleterious materials such as clods, coarse objects and rocks. At least eighty-five percent (85%), by volume, of shredded bark shall conform to the sizes specified.

8. Mulch all exposed soil surfaces twenty-four (24) hours after planting with a minimum depth three inches (3”) of tree bark or wood chips. Do not placed mulch directly against the trunk of the tree.

2.6 GRAVEL MULCH

2.6.1 Gravel mulch work shall consist of furnishing and placing gravel mulch, including site preparation, edging, and weed control fabric as shown on the plans.

2.6.2 The color of gravel shall be as stated in the Statement of Work.

2.6.3 The Contractor shall submit a gallon container sample of gravel to the Engineer for approval prior to delivery of materials to the site.

2.6.4 Weed control fabric shall be manufactured from thermally spun bonded polypropylene fabric and shall conform to the following:

Specification Minimum Requirement Grab Tensile Strength 81/79 lbs Grab Elongation 60/63% UV Resistance 70% @ 150 hours Mass 3.24 oz/sq/yd

2.6.5 Staples shall be two inches (2”) wide, eight inches (8”) in length, and 11 gauge wires.

2.6.6 A copy of the manufacturer’s product sheet together with instructions for installation shall be furnished to the Engineer 5 days before installation.

2.6.7 Areas to receive gravel mulch shall be cleared of trash and debris. After clearing, the areas to receive gravel mulch shall be excavated to the depth shown on the plans, graded to a smooth surface, compacted to not less than 80% relative compaction.

2.6.8 After clearing, areas to receive gravel mulch shall be excavated to a sufficient depth such that the finished elevation of the gravel mulch will meet original finish grade or proposed finished grade.

2.6.9 Surplus excavated material shall become the property of the Government.

2.6.10 Weed control fabric shall be placed in areas to receive gravel mulch. Weed control fabric shall be placed loosely with longitudinal and transverse joints overlapped twelve inches (12”). Following placement, the fabric shall lie flat, smooth and be in uniform contact with the soil surface, without bulges or wrinkles. Fabric shall be stabled or staked in place to keep fabric in place during gravel placement and compaction.

2.6.11 Gravel mulch shall be placed as a single three inch (3”) layer. Each layer of gravel mulch shall be raked to evenly blend various material sizes forming a smooth uniform surface.

2.6.12 When placement is complete the surface shall be uniform, maintain original flow lines, slope gradient and contours of the project site.

2.7 ROOT BARRIERS – Linear Style Planting

2.7.1 Root barriers shall be black, extruded panels of 0.080” wall thickness in modules of thirty-six (36”) high by twenty-four inches (24”) long. Panels shall be manufactured with homopolymer polyethylene with added ultraviolet inhibitors.

All root barrier panels shall vertically interlock vertically, to prevent roots from prying the panels apart.

Exhibit A

2.7.2 The vertical root directing ribs shall be facing inwards toward the root ball and the top edge shall be half inch (½”) above grade. Each of the required number of panels shall be joined in a linear fashion and placed along the adjacent curb.

2.7.3 To determine the correct number of panels to be used, contractor shall take the anticipated mature canopy diameter of the tree and add two (2) feet. This will be the number of feet necessary for a linear style planting application.

For One Side of Tree

Expected Tree Feet of Number of Canopy at Maturity Barrier Panels

12’ (3.6m) Dia. +2’ (61cm) = 14’ (4.2m) 7 Panels 18’ (5.5m) Dia. +2’ (61cm) = 20’ (6.1m) 10 Panels 24’ (7.3m) Dia. +2’ (61cm) = 26’ (7.9m) 13 Panels

2.8 STAKES AND GUY WIRES

2.8.1 Plants to be staked shall be staked at the time of planting as shown on the plans or in the Statement of Work. Two stakes shall be installed on opposite sides of the plant in a transverse direction to the prevailing wind one foot away from the root-ball of the plant to a minimum of twenty-four inches (24”) below finished grade.

2.8.2 Stakes shall be of sufficient lengths to support each plant in an upright position.

Tree stakes shall be either two inch (2”) nominal diameter round stakes or two inch by two inch (2” x 2”) nominal size square stakes, at the Contractor’s option.

2.8.3 After installation of the tree stakes, the height of each stake shall be a maximum of two inches (2”) above the tree tie.

2.8.4 Each plant requiring stakes shall be tied with one tie to each stake. The ties shall be installed at the lowest position which will support the plant in an upright position. Ties should provide flexibility, but not allow the trunk to rub against the stakes. Tie shall be of extruded vinyl-base tape, one inch (1”) wide and a minimum of 10 mils thick. Each tie shall form a figure eight by crossing the tie between the plant and stake, and the figure eight shall be formed twice. Each end of the tie then shall be wrapped one and one-half (1-1/2) turns around the stake and securely tied.

2.8.5 Guy wire assemblies shall be used on all evergreen trees ten feet (10’) and taller and all deciduous tree three inches (3”) and greater in caliper.

2.8.6 Three guy wires shall be spaced equally about each tree at approximately 120 degrees between each guy. Each guy shall consist of two strands of galvanized #12 gauge wire and be attached to the tree at an angle of approximately 45 degrees at about one-third (1/3) to one-half (1/2) the height of the tree.

2.8.7 12mm or ½” (half inch) reinforced black rubber hose shall be used to encase guy wires and prevent direct contact with the bark of the tree.

2.8.8 Each guy shall be anchored in the ground using a Duckbill anchor or an approved equal. Drive anchor approximately Twenty-four inches (24”) below finished grade.

2.8.9 Each guy shall be made taut using six inch (6”) turnbuckles.

2.8.10 Brightly colored flagging tape shall be attached to each guy for the duration of the tree support.

2.8.11 Tree stakes and guy wires shall be removed once the trees are stable. Tree stakes and guy wires should remain for a maximum of two years.

2.9 FILTER FABRIC

2.9.1 The fabric consists exclusively of manmade thermoplastic fibers, is a non-woven geo-textile fabric, and forms a mat of uniform quality. Fabric fibers are continuous and random throughout the fabric. The fabric shall be medium weight (6oz to 8oz), 100% polypropylene needle punched that is heatset. The filter fabric shall meet the requirement for AASHTO M-228 for Class 2 applications.

2.9.2 The fabric is mildew resistant and rot-proof and it is satisfactory for use in a wet soil and aggregate environment..

2.9.3 Following placement, the fabric shall lie flat, smooth and be in uniform contact with the soil surface, without bulges or wrinkles. Fabric shall be stabled or staked in place to keep fabric in place during gravel placement and compaction.

2.10 POST EMERGENT HERBICIDE

“Round Up” or approved equal may be utilized in the planting area to control weeds until final acceptance by the Government. All chemicals must be applied by a licensed Chemical Applicator.

2.11 PLANTING MIXTURE

Soil for use in back-filling tree pits shall be excavated soil from the planting pit unless otherwise specified by the Government. Soil with poor drainage is unsuitable to be used as back-fill. Immediately dispose of unsuitable subsoil from the landscape excavation.

Do not mix with amendments or use as back-fill.

2.12 HYDRO-SEEDING

2.12.1 The soil stabilizing emulsion blend to be applied shall be a true emulsion consisting of two completely immiscible liquids, in which minute globules of one liquid are dispersed but not dissolved throughout the other liquid. The blend must also be manufactured exclusively with generally regarded as safe (GRAS) materials.

2.12.2 The soil stabilizing emulsion blend to be used shall consist of at least (3) three different linear anionic copolymer of acrylamide/sodium acrylate in water-in-oil emulsions, lending distinct molecular weights greater than 12x106 and anionic mole percentages (charge density) greater than 25%, within one emulsion. The blend must be guaranteed to contain 30% (+/- 1%) active polymer, in which all of the active particles are ultra fine in size. The blend shall also be guaranteed to have 100 ppm or less of residual acrylamide.

2.12.3 The soil stabilizing emulsion shall be nontoxic to plant and animal life. It must also be registered and licensed by the State of California, Department of Food and Agriculture, as an “auxiliary soil amendment.”

2.12.4 The fiber to be used shall be either of wood fiber, paper fiber or a combination of the two and shall be produced from natural or recycled (pulp) fiber, such as wood chips or similar wood materials or from newsprint, and shall be free of synthetic or plastic materials. Fiber shall not contain more than 7 percent ash as determined by the Technical Association of the Pulp and Paper Industry (TAPPI) Standard T 413, shall contain less than 250 parts per million boron and shall be otherwise nontoxic to plant or animal life.

2.12.5 Fiber shall have a water-holding capacity by mass of not less than 1200 percent.

Fiber shall be of such character that the fiber will disperse into a uniform slurry when mixed with water. Water content of the fiber before mixing into slurry shall not exceed 15 percent of the dry mass of the fiber. The percentage of water in the fiber shall be determined by California Test

2.12.6 Fiber shall have the moisture content of the fiber marked on the package. Fiber shall be colored to contrast with the area on which the fiber is to be applied, and shall not stain concrete or painted surfaces. A Certificate of Compliance for fiber shall be furnished to the Engineer.

2.12.7 The seed to be applied shall be as shown on the plans and/or specified within the Statement of Work.

Seed shall be labeled by the vendors supplying the seed. Seed shall have been tested for purity and germination not more than 12 months prior to the application of the seed. The test results from seed testing shall be delivered to the Engineer prior to applying the seed. Seed labels furnished by the seed vendors supplying the seed shall indicate the purity, germination and pure live seed as determined by testing.

2.12.8 Mixing of materials for application with hydro-seeding equipment shall be performed in a tank with a built-in continuous agitation system of sufficient operating capacity to produce a homogeneous mixture and a discharge system which will apply the mixture at a continuous and uniform rate. The tank shall have a minimum capacity of 1,000 gallons. The Engineer may authorize use of equipment of smaller capacity, if it is demonstrated that the equipment is capable of performing all operations satisfactorily.

2.12.9 A dispersing agent may be added to the mixture provided the Contractor furnishes evidence that the additive is not harmful. Any material considered harmful, as determined by the Engineer, shall not be used.

2.12.10Any mixture containing stabilizing emulsion shall not be applied during rainy weather or when soil temperatures are below 40 degrees F. Pedestrians or equipment shall not be permitted to enter areas where mixtures containing stabilizing emulsion have been applied.

2.13 WATER

All one (1) and five gallon plants shall be watered at the rate of one (1) gallon per minute for a minimum of twenty (20) minutes. All fifteen gallon plants shall be watered at the rate of one (1) gallon per minute for a minimum of forty-five (45) minutes. All twenty-four (24) and thirty-six (36) inch boxed or burlap trees shall be watered at the rate of one

(1) gallon per minute for a minimum of two (2) hours. All trees larger than thirty-six (36) inch containers shall be watered at the rate of one (1) gallon per minute for a minimum of six (6) hours.

Where watering is done with a hose, a hose bubbler shall be used. If a hose bubbler is not available the Contractor shall set the water gpm in the presence of the Project Inspection or Engineer. The rate shall be no grater than one (1) gallon per minute. Under no circumstances shall the full force of the water from the open end of a hose be allowed to create holes or pockets within the basin or surrounding soil of any plants.

After watering all plants, Contractor shall adjust vegetation as necessary to correct depth of planting, vertical alignment and/or to compensate for settling. Soil shall be firmed around each plant as final adjustments are made.

2.14 MISCELLANEOUS MATERIALS

All other materials not specifically described but required for a complete and proper installation may be selected by the Contractor subject to the approval of the Government.

PART 3 EXECUTION

3.1 TREE PLANTING

3.1.1 No planting shall be done in any area until the area concerned has been prepared in conformance with these specifications and the Statement of Work and presents a neat and uniform appearance satisfactory to the Engineer. When an irrigation system is required, the irrigation system shall be installed and checked for coverage to the satisfaction of the Engineer prior to planting plants.

3.1.2 A certified tree arborist must be present at the planting of all trees which are thirty-six (36) box size or larger. If there are girdling roots, girdling roots are those that are growing around the base of the trunk, and as they grow basically end up strangling the tree over time, the tree shall not be planted. The Contractor is to remove tree, if the certified arborist cannot correct the problem on site and guarantee the health of the tree.

3.1.3 Layout individual tree locations and areas for multiple plantings. Stake locations and outline areas and secure the Government’s approval before start of planting work. Make minor adjustments as may be requested by the Government.

3.1.4 Where shrubs are shown on the plans to be planted in groups, the outer rows shall be parallel to the nearest roadway. Shrubs in adjacent rows shall be staggered.

Adjustment in the number or alignment of plants shall be made between the outer rows.

3.1.5 Where vines are to be planted against walls or fences, the vines shall be planted as close as possible to the wall or fence as shown on the plans.

3.1.6 Plants shall be removed from their containers in such a manner that the root-ball of earth surrounding the roots is not broken. Plants shall be planted and watered as herein specified immediately after removal from their containers. Plant containers shall not be cut prior to delivery of the plants to the planting area.

3.1.7 Roots of plants not in containers shall be kept moist and covered until the plants are planted.

3.1.8 Excavate pits, beds, and trenches according to drawings with vertical but “rough” sides. Avoid creating smooth or “glazed” sides of pit. Leave soil in bottom of pit undisturbed.

3.1.9 All tree pits shall be two and a half (2-1/2) times the width of the root ball and be no deeper than the root ball to avoid settling. Do not excavate tree pits until preliminary approval has been obtained from the Government. All trees shall be planted two inches (2”) above the existing or anticipated grade.

3.1.10 All other plantings pits shall be one and a half (1-1/2) times the width of the root ball and excavated eighteen (18) inches deep. Backfill pits with amended soil.

Compact soil under the root ball to avoid settling. All shrubs, perennials and groundcover shall be planted one inch (2”) above the existing or anticipated grade.

3.1.11 Immediately dispose of unsuitable subsoil removed from landscape excavations off site. Do not mix with planting soil or use as back-fill.

3.1.12 Soil samples shall be taken as directed by the Statement of Work. The soil samples shall be taken at a depth of two feet (2’). All samples shall be sent to a soil laboratory for analysis of the pH levels, nutrients, and texture. The Contractor shall submit a copy of the soil’s report to the Government. No soil amendments other that what is named in the Statement of Work shall be permitted without the written consent of the Government.

3.1.13 Existing utilities shall be field located prior to excavating. Notify the Government of potential conflicts.

3.1.14 If rock, underground construction, or other obstructions are encountered in excavation for the planting of trees, notify the Government. New locations may be selected by the Government, or change order may be issued to direct removal of obstructions to depth of not less than six inches (6”) below required planting depth.

3.1.15 Test all tree planting pits for adequate percolation. If no trees are to be planted follow the soil test requirements per the Statement of Work. If subsoil conditions indicate retention of water in planting areas, or if seepage or other evidence indicating presence of underground water exists, notify the Government before backfilling. A change order may be issued to direct installation of a vertical drain or other measures beyond drainage requirement indicated.

3.1.15 Before backfilling, clean soil of roots, plants, sod, stones, clay lumps, and other extraneous materials harmful or toxic to plant growth, and dispose of off site. Use only existing soil from the site as back-fill.

3.1.16 Set balled and burlapped stock on undisturbed soil, plumb and in center of pit or trench with top of ball two inches (2”) above finished landscape grade. Remove burlap from top of root-ball, but do not remove from sides or under root-ball.

Completely remove any nylon, plastic, or wire materials from the top half of the root-ball. Remove pallets, if any, before setting. Do not use stock if ball is cracked or broken before or during planting operation. When set, place backfill (existing native soil) around base and sides of ball, and work each layer to settle backfill and eliminate voids and air pockets. When excavation is approximately two-thirds (2/3) full, add water until backfill material is saturated. Place remainder of backfill. Repeat watering until no more is absorbed. Water again after placing the three inch (3”) mulch layer.

3.1.17 Nursery stakes in plants containers stored at the project site shall be removed before transporting the plants to the planting areas, unless otherwise directed by the Engineer.

3.1.18 Set container grown stock the same way as specified for balled and burlapped stock, except remove container before setting. Carefully remove cover and sides of wooden boxes after partial backfilling so as not to damage root-balls.

3.1.19 Plants shall be planted in such a manner that the roots are not restricted or distorted. Encircling roots shall be removed.

3.1.21 Construct water retention basin as directed in plans, at least three inches (3”) high and twice the diameter of the root-ball.

3.1.22 Mulch pits, trenches, and planted areas. Provide a minimum three inch (3”) layer of mulch on top of the root-ball. Keep mulch six inches (6”) away from the trunk of the tree.

3.1.23 Unless otherwise directed by the Government, do not cut tree leaders, and remove only injured or dead branches. Any pruning shall be in accordance with the Care and Maintenance Southern California Native Plant Gardens by Bart O’Brien, Betsey Landis, and Ellen Mackey. Stake or guy trees immediately after planting.

If after pruning, the plant has become misshapen or changed in appearance, the plant will be rejected.

3.1.24 Stake deciduous trees less than (>) three inches (3”) in caliper and evergreen tree less than ten feet (10’) tall. Trees that require staking shall be staked in accordance with the tree planting and staking details shown on the drawings.

3.1.25 Two stakes shall be installed on opposite sides of the plant in a transverse direction to the prevailing wind one foot away from the root-ball of the plant to a minimum of twenty-four inches (24”) below finished grade.

3.1.26 Stakes shall be of sufficient lengths to support each plant in an upright position.

Tree stakes shall be either two inch (2”) nominal diameter round stakes or two inch by two inch (2” x 2”) nominal size square stakes, at the Contractor’s option.

3.1.27 Planting done in soil that it too wet or too dry or not properly conditioned, as provided in these specifications or the Statement of Work will not be accepted.

No payment will be made for this planting and any further planting work will be suspended until the Contractor has complied in every way with the specification.

3.1.28 Trees shall be planted first in planter areas, followed by shrubs and groundcover.

3.1.29 Mulch shall be applied at the depth shown on the plans or specified in the

Statement of Work. When a depth is not shown, the minimum depth shall be three (3) inches no matter what type of mulch. It shall be placed in areas as shown on the plans. Mulch placed in plant basins shall not come in contact with the plant crown and stem.

3.1.30 Plants shall be watered in conformance with the provisions in Section 2.13.

Water shall be applied to plants as often and in sufficient amounts as conditions may require keeping the plants in a healthy, growing condition until final acceptance by the Government. Any additional watering measures required to maintain the plants in a healthy, growing condition shall be furnished by the Contractor at the Contractor’s expense.

3.2 FINAL CLEAN UP

Before final inspection of the work, the Contractor shall clean the material sites and all ground occupied by the Contractor in connection with the work of all rubbish, excess materials, false work, temporary structures and equipment. All parts of the work shall be left in a neat and presentable condition. Full compensation for final cleaning up will be considered as included in the prices paid for the various contract items of work and no separate payment will be made therefore.

3.3 REPLACEMENT

3.31 Plants that show signs of failure to grow at any time, or which are so injured or damaged as to render them unsuitable for the purpose intended, as determined by the Engineer, shall be removed and replaced. Unless otherwise permitted by the Engineer, the Contractor shall complete replacement of unsuitable plants within 2 weeks after the Engineer marks or otherwise indicates that the plant(s) shall be replaced.

3.32 Replacement planting shall conform to the original spacing and size provisions specified for the plants being replaced.

3.33 Replacement plants shall be the same species as the plants being replaced, or the

Contractor and Engineer may agree to the substitution or alternate species of plants to be used as replacements in conformance with the provisions in the Section 3.2.3.

3.34 Replacement plants shall be furnished and planted by the Contractor at the

Contractor’s expense. At the option of the Contractor, plants of larger container size than those originally specified may be used for replacement plants during the warranty period. The use of plants of a larger container size than those originally specified for replacement plants shall be at the Contractor’s expense.

3.4 MAINTENANCE PERIOD

Maintenance period for all new native plant vegetation shall be for one-hundred twenty-three (123) days beginning the first day of May and ending on the last day of August the same year. Plants shall be watered in conformance with the provisions in Section 2.13.

Weeds shall be removed by hand within the plants root zone and tree drip lines. Weeds outside this area maybe sprayed with chemicals. All trash and debris shall be properly disposed off.

3.5 WARRANTY PERIOD

Warranty period for all plant material shall be for one (1) year after date of final acceptance of the project by the Government. Warranty is against defects including death and unsatisfactory growth, but excepting defects resulting from neglect by the Government, abuse or damage by others, or incidents which are beyond Contractor’s control.

END OF SECTION 07000