3.2.200 Landscape Conservation.
Landscape Conservation prevents the indiscriminate removal of significant trees and other vegetation, including vegetation associated with streams, wetlands and other protected natural resource areas. This section cross-references BDC 2.7.600 and 2.7.700, which regulate development of areas of special interest.
The purpose of this section is to incorporate significant native vegetation into the landscapes of development. The use of existing mature, native vegetation within developments is a preferred alternative to removal of vegetation and re-planting. Mature landscaping provides summer shade and wind breaks, allows for water conservation due to larger plants having established root systems, and assists with erosion control within disturbed construction sites.
A. Applicability. The standards in this section shall apply to all development sites containing significant vegetation, as defined below, except for residential development on Residential District lots that were created through a subdivision or partition plat filed with Deschutes County prior to the effective date of the ordinance codified in this code.
B. Significant Vegetation. Significant vegetation means individual trees with a specific trunk diameter as measured four feet above the ground (known as DBH, “diameter at breast height”); shall be inventoried during the site design process and protected during construction unless otherwise approved for removal through the site plan review process. For the purpose of this section, deciduous trees measuring six inches or greater and coniferous trees measuring 10 inches or greater shall be considered significant vegetation.
C. Mapping and Protection Required. A Tree Protection Plan shall be prepared and submitted with the development application. Significant vegetation shall be inventoried and mapped as required by BDC Chapter 4.2, Site Plan Review and Design Review, BDC 2.7.600, Waterway Overlay Zone (WOZ), and 2.7.700, Upland Areas of Special Interest Overlay Zone. Trees shall be mapped individually and identified by species and size (DBH). A protection area shall be defined around the edge of all branches (drip-line) of each tree (drip-lines may overlap between trees) or stand of trees. The City also may require an inventory, survey, or assessment prepared by a qualified professional when necessary to determine tree health, vegetation boundaries, building setbacks, and other protection or mitigation requirements.
D. Protection Standards. Significant trees identified as meeting the criteria in subsection (B) of this section must be retained unless approved by the City to be removed for development. Preservation is considered impracticable when it would prevent development of public streets, public utilities, needed housing or land uses permitted by the applicable land use district. The term prevent in this standard means that the development cannot be designed to avoid the significant tree(s). An inability to achieve maximum permitted density by complying with this subsection must not in itself be considered to prevent development. Building envelopes commensurate with the lot coverage standard of the zone must be depicted on the Tree Protection Plan. Trees outside the envelope must be protected unless they prevent development. In instances where applying exceptions to certain development standards would make tree preservation practical, the City may allow one or more of the following exceptions to the development standards when individual trees with a DBH of 24 inches or larger or stands of trees that are in good health as determined by a qualified professional, are preserved by a proposed development with an approved tree preservation plan:
•Reductions of setbacks up to 25 percent.
•Increased lot coverage up to 15 percent.
•Reduced landscape coverage up to five percent.
1. Protection of Significant Trees. The applicant must submit a Tree Protection Plan on a site plan map, drawn to scale, that includes the following provisions where appropriate:
a. Inventory of Significant Vegetation. Depict all significant vegetation by DBH and species, showing property lines, two-foot contours and rock outcroppings.
b. Building Envelopes. The developer shall depict the buildable area of a lot that is consistent with the lot coverage area of the zone.
c. Barriers. The developer shall depict protection barriers on the site plan and locate and mark with flagging and/or signs all construction roads, parking places for workers, and areas for the storage of building materials, gravel and soil; stake out the exact locations of all utility trenches; erect physical barriers around all trees to be retained or groups of trees around the work site. Barriers that extend beyond the drip-line of the tree are preferred.
d. Soil Compaction. The Tree Protection Plan shall depict typical details of methods for protecting the critical root zone. If barriers are not feasible to keep away vehicles and foot traffic, use six to eight inches of wood chips spread over the root zone or bridge root area overlaid by plates of steel or other suitable material.
e. Grade Changes. If a grade change is unavoidable, retaining walls shall be used to protect the root system.
f. Severing Roots. Avoid cutting anchoring roots if possible. Tunneling for smaller household utility lines may be an option for tree preservation. When root cuts are unavoidable, the cuts shall be made with a pruning saw.
g. Above-Ground Injuries to Trees. Do not use trees for posting signs, electrical wires and pulleys. Keep trees free of nails, screws, and other fastening devices. Prevent trunk injuries by surrounding trunk with one-inch by four-inch wooden slats and securing in place with gauge wire around slats.
h. Soil Contamination. Altering the soil chemistry can result in weakened trees, making them more susceptible to insects and disease. Prevent adverse effects on soil chemistry by spreading heavy plastic tarping where concrete is to be mixed or sheet rock cut; do not clean paintbrushes and tools over tree roots; dispose of chemical wastes properly and do not drain onto soil.
i. Altering the Natural Drainage Course. When the natural drainage of a site is altered, watering for existing trees must be augmented by an irrigation system. Prior to site grading, prepare a site drainage plan. Sometimes surface water containment can sustain existing stands of trees without artificial irrigation.
2. The City may approve the provision for substituting the retention of smaller trees in lieu of significant trees if it can be determined by a qualified professional that the small trees have equal or greater measurable benefits as specified in the purpose of this section and/or that the significant trees will not survive.
3. All existing trees in good health, as determined by a qualified professional, which are located within the front yard setback or within an undeveloped public right-of-way shall be conserved whenever practical.
4. When the removal of significant trees cannot be avoided, the City may require, as part of the required landscaping plan for the development site, the replacement of trees in size and number equivalent to the square inch measurement at DBH.
E. Construction. All areas of significant vegetation shall be protected prior to, during, and after construction. Grading, operation of vehicles and heavy equipment, and storage of supplies and construction materials are prohibited within significant vegetation areas, except as approved in writing by the City for installation of utilities or streets. Such approval shall only be granted after the City concludes in writing that there is no other reasonable alternative to avoid the protected area, and any required mitigation is provided in conformance with BDC 1.3.300(C), Mitigation for the Removal of Vegetation. The written approval shall include the specific facts that support the conclusion.
F. Performance Bond. To ensure that the significant trees identified through the development review process will be retained and protected, the Review Authority may require the developer to post a performance bond in an amount determined by the size of the trees being preserved as shown below:
|
Tree Size |
Bond Amount |
|---|---|
|
4 – 6 inches DBH |
$1,000 |
|
6 – 10 inches DBH |
$1,500 |
|
10 – 16 inches DBH |
$3,000 |
|
Greater than 16 inches DBH |
$5,000 |
The amount of the required performance bond shall be determined by totaling the number of trees being preserved based on size and bonding value in the above table. The developer may utilize one of the following methods to assure full and faithful performance:
1. A surety bond executed by a surety company authorized to transact business in the State of Oregon in a form approved by the City Attorney.
2. A cash deposit in a City account at an approved lending institution.
3. An irrevocable standby letter of credit from a federally insured banking institution or savings and loan operating in Oregon that unconditionally promises to pay the funds pledged upon demand by the City. Such obligation must be unaffected by the financial status of the person who has obtained the letter of credit.
4. An “assurance provider” arrangement between the developer, the City and a federally insured financial institution which assures the City that funds to mitigate the loss or damage of significant trees identified through the development review process for preservation and protection will be provided by the federally insured financial institution to the City in the event the developer does not perform in conformance with the Land Use Development Agreement, and the federally insured financial institution must be satisfactory to the City.
5. The City may place a second position lien on the subject property. The lien shall accrue interest at the rate of six percent until such time the lien amount has been collected. The lien amount shall be paid to the City in full prior to the final occupancy of a building or final plat recordation of a subdivision or partition plat.
G. Termination of Bond. If the developer fails to carry out the provisions of the agreement, the City shall call upon the bond, or letter of credit or cash deposit or property lien or assurance provider arrangement, to finance any cost or expenses resulting from said failure. If the amount of the deposit, letter of credit, bond, or property lien or assurance provider arrangement exceeds the cost and expense incurred by mitigating the loss or damage of the significant trees, the City shall deposit the remainder into a City account for the purpose of tree preservation education, tree planting and maintenance. If the amount of the deposit, letter of credit, bond or assurance provider arrangement is less than the cost and expense incurred by the City for the improvements and repairs, the developer shall be liable to the City for the difference.
H. Exemptions. The mitigation standards in BDC 1.3.300(C) shall not apply in the following situations:
1. Dead, Diseased, and/or Hazardous Trees. Trees that are dead or diseased, or pose a hazard to personal safety, property or the health of other trees, may be removed if the Planning Director approves a report and recommendation from a certified arborist or other qualified professional. Prior to tree removal, the applicant shall provide a report from a certified arborist or other qualified professional to determine whether the subject tree is diseased or poses a hazard, and any possible treatment to avoid removal, except as provided by subsection (H)(2) of this section.
2. Emergencies. Significant vegetation may be removed in the event of an emergency without land use approval pursuant to BDC Title 4, when the vegetation poses an immediate threat to life or safety, as determined by the Planning Director based on a certified arborist’s report submitted to the City. [Ord. NS-2488, 2023; Ord. NS-2016, 2006]