6.1 General Plant Selection
▶ Instructions: Select and observe all plants at the nursery prior to purchasing, and reject plants that do not meet specifications as set forth in this Guide. Ideally, trees should be purchased from a growing nursery if there is one available locally. You may have to purchase plants from more than one nursery in order to find all plants that are called out on the landscape design plan, or make a Plant Substitution should they be unavailable.
▶ General Observations: All plants should be observed for size, health, quality, character, etc. Purchase healthy stock, grown in a nursery, and reasonably free of die-back, disease, insects, eggs, bores, and larvae. At the time of planting all plants should have a root system, stem, and branch form that will not restrict normal growth, stability, and health for the expected life of the plant. Also, try to observe the root system of all plants before purchasing as well. Check for tamper proof seals that identify the plant. If a particular defect or substandard element can be corrected at the nursery, as determined by you, the agreed upon remedy may be applied by the nursery provided that the correction allows the plant to meet the requirements set forth in this Guide. Plants should be healthy with the color, shape, size and distribution of trunk, stems, branches, buds and leaves normal to the plant type specified:
▶ Crown: The form and density of the crown should be typical for a young specimen of the species or cultivar pruned to a central and dominant leader. Crown specifications do not apply to plants that have been specifically trained in the nursery as topiary, espalier, multi-stem, clump, or unique selections such as contorted or weeping cultivars.
▶ Leaves: The size, color, and appearance of the leaves should be typical for the time of year and stage of growth of the species or cultivar. Trees should not show signs of prolonged moisture stress or over watering as indicated by wilted, shriveled, or dead leaves.
▶ Branches: Shoot growth (length and diameter) throughout the crown should be appropriate for the age and size of the species or cultivar. Trees should not have dead, diseased, broken, distorted, or otherwise injured branches. Main branches should be distributed along the central leader, not clustered together. They should form a balanced crown appropriate for the cultivar/species. The branch diameter should be no larger than two-thirds (one-half is preferred) the diameter of the central leader measured 1 inch above the branch union. The attachment of the largest branches (scaffold branches) should be free of included bark.
▶ Trunk: The tree trunk should be relatively straight, vertical, and free of wounds that penetrate to the wood (properly made pruning cuts are acceptable and are not considered wounds), sunburned areas, conks (fungal fruiting bodies), wood cracks, sap leakage, signs of boring insects, galls, cankers, girdling ties, or lesions (mechanical injury).
▶ Roots: The roots should be reasonably free of scrapes, broken or split wood. A minimum of three structural roots reasonably distributed around the trunk (not clustered on one side) should be found in each plant. Root distribution should be uniform throughout the root ball, and growth should be appropriate for the species. Plants with structural roots on only one side of the trunk (J roots) should be rejected. The root collar should be within the upper 2 inches of the substrate/soil. Two structural roots should reach the side of the root ball near the top surface of the root ball. The root system should be reasonably free of stem girdling roots over the root collar, or kinked roots from nursery production practices.
▶ Plant Substitutions: Speak with your local nurseries to inquire about what plants may be substituted for plants that are shown on the landscape design plan but are not available at the nursery. Staff are typically knowledgeable and will suggest a few plant substitutions that you may choose from.
6.2 Balled and Burlapped Plants
▶ Defined: Field grown plants, with the root ball packaged in a burlap and twine and/or burlap and wire basket package. Twine and burlap used for wrapping the root ball package should be natural, biodegradable material.
▶ Instructions: Balled and burlapped trees that are stored out of the ground should be placed in a holding area protected from extremes of wind and sun with the root ball protected by covering with mulch or straw and irrigated sufficiently to keep moisture in the root ball above wilt point and below saturation. For planting, see x.x. After the root ball has been planted and backfilled, remove all twine and burlap from the top of the root ball. Cut the burlap away but do not fold it down onto the Planting Soil. If the plant is shipped with a wire basket that does not meet the requirements of a “Low Rise” basket, remove the top 6 - 8 inches of the basket wires just before the final backfilling of the tree. Earth root balls should be kept intact.
6.3 Spade Harvested and Transplanted
▶ Instructions: Trees should be harvested prior to leafing out (bud break) in the spring or during the fall planting period except for plants know to be considered as fall planting hazards. Plants that are fall planting hazards should only be harvested prior to leafing out in the spring. Trees should be moved and planted within 48 hours of the initial harvesting and should remain in the spade machine until planted. After installing the tree, loosen the soil along the seam between the root ball and the surrounding soil out to a radius from the root ball edge, equal to the diameter of the root ball to a depth of 8 - 10 inches by hand digging to disturb the soil interface. Fill any gaps below this level with loose soil.
6.4 Container Plants
▶ Instructions: Remove the container. Perform root ball shaving, see x.x. Remove all roots and substrate above the root collar and the main structural roots (see x.x). Remove all substrate at the bottom of the root ball that does not contain roots. Using a hose, power washer or air excavation device, wash out the substrate from around the trunk and top of the remaining root ball and find and remove all stem girdling roots within the root ball above the top of the structural roots.
6.5 Groundcover, Perennial, and Annual Plants
▶ Instructions: Container or flat-grown plants should be sized as noted in the planting plan. Plants should be well-rooted and healthy. Assure that soil is moist, but not wet or muddy. prior to planting. Irrigation, if required, should be applied at least 12 hours prior to planting to avoid planting in muddy soils. Assure that the soil grades in the beds are smooth and at the correct elevation. Plants should be planted in even, triangularly spaced rows, at the intervals called out for on the Landscape Plan, unless otherwise noted. The first row of Annual flower plants should be 6 inches from the bed edge unless otherwise directed. Dig planting holes sufficiently large enough to insert the root system without deforming the roots. Set the top of the root system at the grade of the soil. Schedule the planting to occur prior to application of the mulch. If the bed is already mulched, pull the mulch from around the hole and plant into the soil. Do not plant the root system in the mulch. Pull the mulch back so it is not on the root ball surface. Press the soil to bring the root system in contact with the soil and spread any excess soil around, in the spaces between plants. Apply mulch to the bed, making sure not to cover the tops of the plants or the tops of the root ball with mulch. Water each planting area as soon as the planting is completed. Apply additional water to keep the soil moist without over watering.
6.6 Fabric Container Plants
▶ Instructions: Remove the fabric container from the root ball. Cut the roots at the edge of the container as needed to extract the fabric from the roots. Make clean cuts with sharp tools; do not tear the roots away from the fabric. Observe the root system after the container is removed to confirm that the root system meets the quality standards (see x.x).
6.7 Bare Root Plants
▶ Instructions: Dig the planting hole to the diameter of the spread of the roots, to a depth in the center that maintains the root collar at the elevation of the surrounding finished grade and slightly deeper along the edges of the hole. Spread all roots out radial to the trunk in the prepared hole making the hole wider where needed to accommodate long roots. Root tips should be directed away from the trunk. Prune any broken roots removing the least amount of tissue possible. Maintain the trunk plumb while backfilling soil around the roots. Lightly tamp the soil around the roots to eliminate voids and reduce settlement.
▶ Instructions: Palm trees should be placed at grade making sure not to plant the tree any deeper in the ground than the palm tree originally stood. The trees shall be placed with their vertical axis in a plumb position. All backfill shall be native soil except in cases where you are planting in rock. Water-settle the back fill. Provide a watering berm at each palm. Berms shall extend a minimum of 18 inches out from the trunk all around and shall be a minimum of (6) inches high. Remove any twine that ties fronds together after placing the palm in the planting hole and securing it in the upright position.