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United States Air Force Academy Standards

EROSION CONTROL, REVEGETATION AND TREE CARE STANDARDS 01351 - 1

June 2013

SECTION 01 35 10: EROSION CONTROL, REVEGETATION AND TREE CARE STANDARDS

PART 1 – GENERAL

1.0 Erosion Control, revegetation, and tree care is required when any project disturbs the soil, vegetation, or trees, and other site stabilization approaches (i.e. landscaping, sod, hardscape) is not part of the project. Compliance with the following is mandatory to promote the restoration and resource protection required by the Integrated Natural Resources Management Plan, Integrated Noxious Weed Management Plan, Preble’s Meadow Jumping Mouse Conservation Agreement, Construction Storm water Pollution Prevention Plan (as applicable), and Municipal Storm Water Permit issued to the U.S. Air Force Academy (USAFA). Any deviation from these standards must be approved by the Contracting Officer (CO) and/or USAFA Natural Resources (10 CES/CEAN). Other Landscaping requirements outlined in the USAFA Design Standards shall also be followed.

Contractors shall consult with USAFA Natural Resources for assistance in understanding these standards and implementing an acceptable site reclamation plan. Particular attention should be given to the requirements for seedbed preparation, supplemental topsoil, native seed mixes and planting techniques, and erosion control materials and installation.

To prevent the introduction and spread of noxious weeds and other non-native plants, all equipment shall be thoroughly cleaned of dirt, seed, and plant parts prior to entering the base.

To the extent possible, Contractors shall minimize creating new roads and trails around the project area. Any new trails, roads, parking areas, or staging areas shall be closed, signed, and rehabilitated as part of the project.

As part of the Environmental Deliverables List, Contractors shall provide invoices, trip tickets, tags, or other documentation to verify that the specified type, quantity, and quality of seed, topsoil, erosion fabric, and other materials is installed per the standard.

1.1. SITE PREPARATION

A. SOIL PREPARATION. All disturbed areas shall be tilled on the contour to a minimum depth of four inches, and then harrowed, raked or rolled to produce a firm seed bed. Imported topsoil (see 1.1.B) may be required to provide an acceptable planting medium. Large rocks (>3 inch diameter) and debris that may impede seeding shall be cleared from the site. Any required erosion control features (e.g., water bars, berms, basins, turnouts) shall be constructed prior to seeding. No fertilizers shall be applied to the seeded area. Sites that are not adequately prepared prior to seeding (e.g., compacted soil, insufficient topsoil, rocky, eroded surface, etc.)

shall be rejected.

B. TOPSOIL. All areas to be revegetated shall be topsoiled with at least 3 inches of quality soil as described below unless the requirement is waived by the Contracting Officer with concurrence from the USAFA Natural Resources office. Where possible, the upper 2-3 inches of the native soil shall be salvaged for re-distribution on the restoration area. If necessary, additional topsoil shall be imported to meet the 3” minimum requirement. Imported topsoil shall be free of rocks, noxious weeds, large woody debris, trash, or other non-soil materials. Topsoil (native or imported) shall not be used from areas infested with noxious weeds. Both the native and imported topsoil shall be lightly disked on the contour to reduce compaction and to fully mix the soils.

Prior to spreading the topsoil, a laboratory soil analysis of a composite soil sample (native and/or imported soils) shall be submitted as part of the Environmental Deliverables List for evaluation of the soils suitability for native revegetation. An acceptable topsoil shall have a loam, sandy loam, clay loam, or silt loam texture; a neutral pH; a low salt content; an organic matter content >2%;

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June 2013 and adequate nutrients to support native grasses. If the topsoil does not meet these criteria, soil amendments (such as compost or other imported soils) shall be required to meet the standard.

1.2. PLANT MATERIALS FOR REVEGETATION

A. NATIVE SEED. Depending on the site conditions, and in coordination with USAFA Natural Resources, one of the following native seed mixes shall be used for revegetating disturbed areas.

Other seed mixes may need to be developed for unique situations on a case-by-case basis. All seed mixes shall consist of certified seed varieties that are free of noxious weeds and have been tested for purity and germination within one year of the planting date. Locally adapted seed ecotypes collected from a similar elevation (6300-8000’at USAFA; 9000’ at Farish Recreation Area) and precipitation zone (15-20 inches) shall be used. Certification labels which indicate the species, purity, germination, weed content, origin, and test date shall be submitted as part of the Environmental Deliverable List for all seed materials. If the seed is to be broadcast by hand, mechanical spreader or hydro-seeder, the seeding rate shall be doubled.

1. Xeric (dry) areas with a variety of soil and slope conditions shall be planted with the following seed mix:

SPECIES (Variety) PLS RATE PER ACRE

DRILL SEEDING

PLS RATE PER ACRE

BROADCAST SEEDING

Perennial Ryegrass (Tetraploid) Lolium perenne

6.0

12.0

Little Bluestem (Camper) Schizachyrium scoparium

3.0

Blue Grama (Hachita) Bouteloua gracilis

1.5

Side Oats Grama (Vaughn) Bouteloua curtipendula

3.5

7.0

Green Needlegrass Stipa viridula

0.5

1.0

Sand Dropseed Sporobolus cryptandrus

0.05

0.10

Western Wheatgrass (Arriba) Pascopyrum smithii

Slender Wheatgrass (San Luis) Elymus trachycaulus

2.0

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2. Forest and Shrubland areas with a variety of soil and slope conditions shall be planted with the following seed mix:

SPECIES (Variety) PLS RATE PER ACRE

DRILL SEEDING

PLS RATE PER ACRE

BROADCAST SEEDING

Little Bluestem (Camper) Schizachyrium scoparium

Blue Grama (Hachita) Bouteloua gracilis

Side Oats Grama (Vaughn)

3.5

7.0

Green Needlegrass Stipa viridula

Sand Dropseed Sporobolus cryptandrus

0.05

0.10

Indian Ricegrass Oryzopsis hymenoides

Mountain Muhly Muhlenbergia montana

Prairie Junegrass Koeleria macrantha

0.5 1.0

3. Mesic riparian areas and wetland fringes shall be planted with the following seed mix:

PLS RATE PER ACRE

BROADCAST SEEDING

Switchgrass (Forrestburg) Panicum virgatum

2.5

5.0

Western Wheatgrass (Arriba)

4.0

Canada Wildrye (Mandan) Elymus canadensis

4.5

9.0

Slender Wheatgrass (San Luis) Elymus trachycaulus

Canadian reed-grass Calamagrostis canadensis

0.25

0.50

Streambank wheatgrass (Sodar) Elymus lanceolatus

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4. Wetland areas shall be planted with 2.5” containerized live plugs on 18” centers and seeded with the grasses identified below. Plugs shall be planted flush with the ground surface and rooted in moist to saturated soil depending on the species’ moisture preference. The quantity of plugs needed, by species, shall be based on the percentages below.

PLS RATE PER ACRE

BROADCAST SEEDING

Canadian reed-grass Calamagrostis canadensis

0.25

0.50

Ticklegrass Agrostis scabra

0.2

0.4

Nebraska sedge Carex canadensis

Plugs – 70%

Plugs – 70%

Creeping spikerush Eleocharis palustris

Plugs – 10%

Torrey’s rush Juncus torreyi

Plugs – 5%

Baltic rush Juncus balticus

Pale bulrush Scirpus pallidus

5. Upland areas at Farish Recreation Area, with a wide variety of slope and soil conditions, shall be planted with the following seed mix:

PLS RATE PER ACRE

BROADCAST SEEDING

Mountain Muhly Muhlenbergia montana

Arizona fescue (Redondo) Festuca arizonica

Western wheatgrass (Arriba)

2.5

5.0

Sideoats grama (Vaughn)

Thickspike wheatgrass (Critana) Elymus lanceolatus

Idaho fescue (Winchester) Festuca idahoensis

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1.3 SEEDING AND MULCHING

A. SEEDING DATES. Seeding shall normally occur within 10 working days of the completion of construction. Fall (September-November) or spring (March-May) planting is preferable to help maximize seed establishment. If the project schedule does not coincide with the preferred seeding periods, or there are unsuitable site conditions (i.e. frozen ground), then soil stabilization and/or storm water Best Management Practices shall be implemented to stabilize the area until the next appropriate seeding date. Any seeding conducted outside the preferred months shall be approved by the CO and/or Natural Resources.

B. SEEDING METHODS. Drill seeding or broadcast seeding shall be used for revegetation. As outlined below, the size and slope of the disturbed area shall determine which seeding method(s) is appropriate and acceptable. Where feasible, rangeland drill seeding combined with a cover of crimped hay mulch or hydro-mulch is the required method of revegetation.

1. Slopes less than 3:1 – Seed shall be planted using a rangeland drill with a small seed/legume box and an agitator box for fluffy or bulky seed. Seed rows shall be spaced 7- 10 inches apart, and planted 0.5 to 0.75 inches deep. The drill shall have double-disk furrow openers with depth bands and packer wheels. Seeding shall be accomplished using bi-directional drilling and following the slope contour. The drill equipment shall be calibrated each day or whenever there is a change in the seed mix to ensure proper seed distribution and rate.

2. Slopes greater than 3:1 or areas less than 0.10 acre – Seed shall be broadcast by hand, mechanical spreader, or hydro-seeding equipment. Broadcasted areas shall be raked or harrowed to incorporate the seed into the soil at a depth not exceeding 0.75 inches. If hydro-seeding is used, the seed shall not be tank mixed with the hydro-mulch and broadcast.

Broadcast seeding shall be avoided when wind speed exceeds 15 miles per hour.

3. Where appropriate, pedestrian and vehicle access to the seeded areas shall be prevented by posting signage (i.e. “Closed for Restoration”) and erecting fencing.

C. MULCHING. Weed-free native hay, weed-free straw, or virgin wood fiber hydro-mulch shall be used to control erosion and promote seed germination and plant establishment. Native hay, straw, or hydro-mulch shall be applied at 2000 pounds/acre on slopes less than 3:1. On steeper slopes, a mulching rate of 2500 pounds/acre shall be used. Native hay or straw shall be crimped into the soil to a depth of at least 3 inches and protrude above the ground at least 3 inches. An organic tackifier shall be used to hold the hay or straw in place if crimping alone is insufficient.

Hydro-mulch shall be applied using a color dye and the manufacturer’s recommended rate of an organic tackifier.

D. EROSION CONTROL MATERIALS. Erosion control blankets, straw coir logs, or soil berms shall be used whenever reclaiming slopes greater than 3:1 or along drainage areas where erosion is probable. All erosion control blanket shall be 100% biodegradable, net-free, wood fiber (excelsior) or coconut fiber materials with at least a two year functional longevity (Western Excelsior Excel S-2 or CC-4 or equivalent). Erosion control fabrics with a plastic netting are strictly prohibited. Manufactured biodegradable stakes (6-inch minimum) or wooden stakes (8-inch minimum) shall be used to anchor any erosion materials; metal staples (8-inch minimum, 8 gauge) may be approved on a case-by-case basis. All erosion control materials shall be installed in accordance with the manufacturer’s instructions and recommendations. Particular attention shall be given to overlapping fabric seams, burying the fabric edges, partially burying coir logs, and utilizing a staple pattern and sufficient number of staples or stakes to prevent the erosion control materials from being dislodged by wind or water.

E. WATERING. Supplemental irrigation shall normally not be necessary or required if the seeding is accomplished during the preferred fall and spring planting periods. If a water hook-up is available

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a sprinkler system may be used to promote rapid plant establishment, but the system must then be operated throughout the first growing season. Generally, watering at 0.75-1.0 inches/week is recommended during the April-October growing season depending on rainfall. Supplemental irrigation of seeded areas using a watering truck is prohibited.

1.4 FINAL INSPECTION AND SEEDING SUCCESS CRITERIA

A. A final inspection of all revegetated areas shall be coordinated with the CO, Construction

Inspector and Natural Resources. If the project is under a Construction Storm Water Permit, the USAFA Water Quality Manager shall also be consulted. Any seeding, topsoil, or erosion control deficiencies noted during the inspection shall be corrected prior to project close-out or final contract payment.

B. A revegetation project shall have at least 3 native grass seedlings/square foot and no bare areas exceeding one square meter after the second growing season. For drill seeded areas, planting rows shall be noticeable by the end of the first full growing season. If a partial or total seeding failure is apparent after the second growing season, poorly vegetated areas shall be reseeded in the same manner described above. Appropriate site preparation shall again be used to create a suitable seedbed for replanting, but any established native vegetation shall be left undisturbed to the extent possible. Areas that erode before establishment can occur shall be repaired and immediately reseeded during the same season.

1.5 CARE OF EXISTING TREES DURING CONSTRUCTION

A. Extreme care shall be exercised in protecting root systems and branches of existing trees.

Trenches shall be placed as far from trees as possible. Absolutely no trenching is permitted within the dripline of any tree. The dripline is the area directly located under the outer circumference of the tree branches. See Appendix A for sketch of tree dripline. Since tree roots extend up to three times the height of the tree, major damage can be incurred by cutting through root systems. Directional boring to minimize root damage should be used to the extent feasible.

Moist conditions shall be maintained during construction. Roots damaged during excavation shall be pruned. Branch pruning shall be minimized, with necessary removal adhering to standard pruning techniques. See Appendix B for additional information on proper pruning techniques.

B. Minimizing damage to trees to be retained within construction areas is critical.

Information on protecting trees during construction activities can be found at www.ext.colostate.edu/PUBS/GARDEN/07420.html

1.6 TREE TRANSPLANTING FROM CONSTRUCTION AREA

A. Whenever possible, existing trees that need to be cleared shall be relocated or sold by Natural Resources as a forest product prior to site clearing. Transplantable trees are generally less than twenty feet in height, although this maximum height will be less under extreme drought conditions due to increased transplant shock in larger trees. Coordinate with Natural Resources at least two months in advance to assess the feasibility of transplanting trees.

1.7 CARE OF TREES MOVED INTO CONSTRUCTION AREA

A. Trees moved into the project area for landscaping purposes shall have irrigation needs addressed for three years, including winter watering. Approximately ten gallons per inch of tree caliper (measured at six inches above ground level) shall be applied to the tree ring area (see “C” below) upon planting. Water shall be applied approximately weekly for the first two months, and then every two to three weeks throughout the remainder of the first growing season, depending on natural moisture and soil conditions. Depending on precipitation, frequency of deep watering during the second and third years may be decreased as the tree continues to establish on the

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site, but newly transplanted trees will likely still require periodic waterings for at least three full growing seasons to maintain tree health and vigor and encourage root establishment. Light watering applications (i.e. sprinklers) will not provide adequate water saturation, tending rather to promote root proliferation within the top several inches of soil instead of encouraging deeper root establishment which is vital to long-term survival. The objective of deep watering is to saturate the root ball to a depth of at least twelve inches. Water amounts on heavy clay soils with poor drainage may need to be lessened to avoid drowning the root system. A rule of thumb is to check the edge of the root ball for moisture at a depth of eight inches. If this area is still moist, watering can be postponed.

B. Winter watering from late October through March is critical, especially in dry climates with desiccating winter winds. Water shall be applied monthly during dry periods, when the ground is not frozen. Fall plantings shall receive a deep watering upon planting, followed by periodic winter watering as conditions warrant. As the tree becomes established, the need for supplemental watering should decrease. This watering regime shall be implemented for at least the first two growing seasons to assist in establishment, but is advisable beyond this timeframe if the transplanted tree is especially large, or is slow in adapting to its new site. See Appendix C for additional information on watering.

C. A soil berm or tree ring of at least four inches in height shall be constructed around the tree (roughly under the tree dripline (outer edge of branches), or at least the size of the transplanted root ball). This will allow water to focus onto the root ball. The berm shall be removed in three years, when roots should have spread well beyond the dripline. Retaining the berm beyond this timeframe tends to lead to subsequent watering only within the bermed area, which will encourage root growth primarily in this area and not outward, to the detriment of the tree.

D. Approximately three to four inches of mulch shall be placed above the root ball to preserve soil moisture, and to protect trees from lawnmower damage in mowed areas. Mulch should not be placed directly against tree stem, as this could cause rotting of wood, and could afford rodents a place to hide and potentially damage tree. A distance of at least six inches from the tree stem should be left unmulched.

E. Transplanted pines are a prime target for the Ips (engraver) beetle, which are attracted to environmentally stressed trees. Landscape planted spruce are highly susceptible to the white pine weevil which can cause significant damage to the tree crown. Transplanted pines and spruce shall be sprayed to prevent bark beetle infestation with a persistent formulation with the active ingredient Carbaryl, as specified on the USAF-approved pesticide list. Spring-planted pine and spruce shall be sprayed within one week of transplanting. Autumn-planted pine and spruce shall be sprayed within one week of planting, and again at the beginning of the following growing season. All pine and spruce shall be sprayed by late March for the following two years. Natural Resources will be available to consult on spraying activities. All pesticide use will be coordinated through the HAZMART and Pest Management Coordinator.

F. In general, trees over six feet in height shall be staked, unless they are not located in a wind-prone location (i.e. sheltered from predominant west/north winds by a building), or do not have a large crown. Stakes shall be removed in one year, unless in unusually windy location, in which case they should be removed after the second growing season. Retaining stakes for too long compromises windfirmness and encourages a tall spindly rather than a sturdy tree trunk.

G. Trees should not be fertilized upon transplanting, as this encourages stem growth at the expense of root growth. Root growth is more critical at this time, so fertilization (nitrogen in particular) is best held off for several years. A root stimulant (generally high in phosphorus) may be used during or immediately after transplanting.

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H. Holes resulting from trees moved from elsewhere on the Academy shall be filled with weed-free soil and graded to ground level within one week of tree removal. Holes shall be marked with three pin flags during the interim.

I. Coordinate with Natural Resources for advice on watering, mulching, spraying, staking, and fertilization.

1.8 MERCHANTABLE WOOD

A. Trees needing removal that are deemed infeasible for transplanting shall be cut and limbed (all limbs removed). Merchantable firewood (tree stems and limbs greater or equal to four inches in diameter) shall be delivered to the NR woodlot at Building 9030. Contractorss may opt to purchase wood at the existing published rate. All wood delivery or purchase shall be coordinated in advance with Natural Resources. Disposition of wood products from Farish Recreation Area shall be determined by Natural Resources.

1.9 TREE SLASH AND STUMP REMOVAL

A. Disposal of woody slash (limb wood and tree tops less than four inches in diameter) is the sole responsibility of the Contractorss. There is no compost yard on base to accept this woody residue. If not removed from the installation, treatment of woody slash shall be approved in advance by Natural Resources. Slash may be chipped and spread onsite to a depth not to exceed three inches, with chips spread at least 30 feet from a road, trail or building. No chips shall be spread in improved or mowed areas. Projects involving small amounts of limb wood may dispose of slash by lopping and scattering onsite only if prior coordination has been made with the Natural Resources. In such cases, the limbs shall be moved at least 50 feet from buildings, roads, or major trails, and lopped and scattered so as not to exceed eight inches above ground level.

B. All rootwads (stumps with attached roots) shall be disposed of off base. These are not merchantable, and are thus not allowed in the Natural Resources woodlot.

C. Where trees are removed but stumps and roots are not extricated, stumps shall be cut as close to ground level as practical, not to exceed two inches (measured on the uphill side of the tree on a slope) above ground level within 25 feet of buildings, roads or major trails, and four inches above ground level elsewhere.

1.10 BRANCH PRUNING

A. Pruning of live branches shall be kept to a minimum, to reduce stress to the tree. Branches requiring removal shall be cut back to the trunk or to an acceptable branch, according to proper pruning procedures. The remaining portions of limbs broken by the passage of equipment shall also be cut back to the trunk or to an acceptable branch. Flush cuts are not acceptable, as these promote decay of the tree stem. Branches shall be cut by saw; not pulled off by heavy equipment. Pruning procedures are outlined in Appendix B.

1.11 BEETLE-INFESTED TREES

A. Trees infested with bark beetles (mountain pine, Ips pine engraver or twig beetles) shall be chipped, debarked, or removed from site to be processed before beetles emerge. If removed from site and not processed in a mill, infested wood should not be placed within five (5) miles of

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any pines, to prevent beetle spread to other areas. Beetle-infested wood shall not be delivered to NR woodlot unless coordinated in advance with Natural Resources.

2.0 CONE COLLECTION

A. Project areas will be examined for developing cone crops, which may be useful for future reforestation needs. A Natural Resources representative will assess this opportunity and, if feasible, coordinate with project manager to collect cones from high quality trees scheduled for removal. Cones ripen in September. Natural Resources would fell trees for collection upon ripening, if this does not hinder construction progress. Trees would be left onsite. Seed from cones would be utilized to grow tree seedlings for future reforestation needs on the Academy.

2.1 LIVE WILLOW STAKING

A. Prior to planting, Natural Resources shall identify all necessary willow staking areas and approve any on-site locations for the harvesting of plant materials. All willow stakes shall be disease- and insect-free (e.g., oyster scale). Off-site plant materials shall only be used with prior approval from Natural Resources.

B. Willow stakes shall be harvested and planted in late-winter to early-spring before plant dormancy is broken (identified by swelling buds). Planting shall only be conducted when the weather and soil conditions allow. Stakes shall not be planted when the ground is frozen or otherwise unsuitable.

C. Live stakes shall be coyote willow (Salix exigua) cuttings that are one-half inch (1/2”) to one-inch (1”) in diameter and at least 4.0-feet (4.0’) in length. Stakes shall be harvested with sharp pruning shears with the base cut at a forty-five degree (45°) angle and a branched top left intact.

All side branches that would be buried below the ground shall be pruned without damaging the branch collar. The butt end of each stake shall be placed in water immediately after cutting to keep them hydrated. All stakes shall be planted within 7 days of harvest.

D. Stakes shall be kept moist, cool and shaded and protected from the wind until installed. During transport or storage the stakes shall be covered to protect them from heat, light and wind damage.

E. Willow stakes shall normally be planted on 2-foot centers in a staggered pattern, but the pattern and spacing may need to be adjusted depending on the availability of groundwater. A planting hole shall be excavated to the groundwater using a hammer drill and a one-inch drill bit, or other approved method. Damage to any erosion blanket shall be avoided to the maximum extent possible. Stakes shall be gently placed in the hole, ensuring that the butt end is seated below the groundwater level. Each hole shall be backfilled, hand-tamped, and/or watered to eliminate air pockets around the stake.

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SECTION 01351 APPENDIX A – “DRIPLINE” SKETCH AND DEFINITION

Dripline: The dripline is the area directly located under the outer circumference of the tree branches.

Because this area contains the highest amount of roots, protecting roots from cutting or compaction is critical. No trenching is permitted within this zone.

SECTION 01351 APPENDIX B – PRUNING TECHNIQUES

Pruning Cuts

Pruning cuts should be made so that only branch tissue is removed and stem tissue is not damaged.

At the point where the branch attaches to the stem, branch and stem tissues remain separate, but are contiguous. If only branch tissues are cut when pruning, the stem tissues of the tree will probably not become decayed, and the wound will seal more effectively.

1. Pruning living branches (Fig. 6)

To find the proper place to cut a branch, look for the branch collar that grows from the stem tissue at the underside of the base of the branch (Fig. 6A). On the upper surface, there is usually a branch bark ridge that runs (more or less) parallel to the branch angle, along the stem of the tree. A proper pruning cut does not damage either the branch bark ridge or the branch collar.

Figure 6A. Targeting the cut http://www.na.fs.fed.us/spfo/pubs/howtos/ht_prune/prun022.htm http://www.na.fs.fed.us/spfo/pubs/howtos/ht_prune/prun023.htm http://www.na.fs.fed.us/spfo/pubs/howtos/ht_prune/prun023.htm

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A proper cut begins just outside the branch bark ridge and angles down away from the stem of the tree, avoiding injury to the branch collar (Fig. 6B). Make the cut as close as possible to the stem in the branch axil, but outside the branch bark ridge, so that stem tissue is not injured and the wound can seal in the shortest time possible. If the cut is too far from the stem, leaving a branch stub, the branch tissue usually dies and woundwood forms from the stem tissue. Wound closure is delayed because the woundwood must seal over the stub that was left.

The quality of pruning cuts can be evaluated by examining pruning wounds after one growing season.

A concentric ring of woundwood will form from proper pruning cuts (Fig. 6B). Flush cuts made inside the branch bark ridge or branch collar, result in pronounced development of woundwood on the sides of the pruning wounds with very little woundwood forming on the top or bottom (Fig. 7D). As described above, stub cuts result in the death of the remaining branch and woundwood forms around the base from stem tissues.

When pruning small branches with hand pruners, make sure the tools are sharp enough to cut the branches cleanly without tearing. Branches large enough to require saws should be supported with one hand while the cuts are made. If the branch is too large to support, make a three-step pruning cut to prevent bark ripping (Fig. 6C).

1. The first cut is a shallow notch made on the underside of the branch, outside the branch collar.

This cut will prevent a falling branch from tearing the stem tissue as it pulls away from the tree.

2. The second cut should be outside the first cut, all the way through the branch, leaving a short stub.

3. The stub is then cut just outside the branch bark ridge/branch collar, completing the operation.

2. Pruning dead branches (Fig. 6)

Prune dead branches in much the same way as live branches. Making the correct cut is usually easy because the branch collar and the branch bark ridge can be distinguished from the dead branch because they continue to grow (Fig. 6A). Make the pruning cut just outside of the ring of woundwood tissue that has formed, being careful not to cause unnecessary injury (Fig. 6C). Large dead branches should be supported with one hand or cut with the three-step method, just as live branches. Cutting large living branches with the three step method is more critical because of the greater likelihood of bark ripping.

http://www.na.fs.fed.us/spfo/pubs/howtos/ht_prune/prun024.htm http://www.na.fs.fed.us/spfo/pubs/howtos/ht_prune/prun025.htm

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SECTION 01351 APPENDIX C – TREE CARE FOLLOWING PLANTING

After planting the tree, build a 4-inch tall berm around the edge of the hole. Fill the berm with mulch (i.e.

shredded bark, compost). The mulch and berm make it easier to water the tree and reduce weed competition. Below are diagrams of a typical tree planting.

Right after planting, water the tree in by filling the bermed basin with water. This will settle the existing soil around the root ball. Fill the bermed basin with water once a week during the growing season, unless natural precipitation is abundant. The goal is to wean the tree slowly off of supplemental irrigation, and get the root system large enough for the tree to thrive on natural rainfall. Continue with winter watering once a month during extended dry periods from late October through March, unless ground is frozen.

REMEMBER: These are just guidelines. Use your index finger to check the soil moisture under the mulch.

More plants are killed by over-watering than by under-watering.

(Portions of this appendix are from Douglas F. Welsh, Landscape Horticulturist Texas A&M University, College Station, Texas).