International Society of Arboriculture

Purpose: To define unacceptable situations which are subject to abatement by the local government.

Notes: Conditions and situations that jeopardize public health and safety are most commonly declared to be public nuisances. Hazardous trees and trees which obstruct travel or line of sight may fall into this category. Situations that threaten the health of the urban forest or are contrary to the community forest management strategy may also be declared nuisances. This second category includes trees which harbor diseases or insect infestations that may readily spread to adjacent trees and species which are considered undesirable. Improper maintenance practices which can lead to tree death or disfigurement have also been declared to be public nuisances in some communities. Abatement procedures are typically contained in a separate provision (see provision 27 - Abatement of hazards and public nuisances).

A. Any tree, shrub or groundcover, growing or standing on private property in such a manner that any portion thereof interferes with any public street, sidewalk, alley or restricts the flow of traffic or visibility of such street, sidewalk, alley or intersection thereof to any person or persons lawfully using such streets, sidewalks, alleys or intersections shall constitute a public nuisance.

[La Habra, CA: City Code Section 12.20.100A]

The following things are public nuisances whenever they may be found within the City of Sacramento:

(a) Any living or standing elm tree or part thereof infected to any degree with the Dutch Elm Disease fungus, Ceratocystis ulmi (Buisman) Moreau [the name is now Ophiostoma ulmi (Buisman) Nannf.]; or which harbors any of the elm bark beetles, Scolytus multistriatus (Marsh.) Or Hylurgopinus rufipes (Eich.);

(b) Any dead elm tree or dead part of any elm tree, including logs, branches, stumps, firewood or other elm material from which the bark has not been removed.

[Sacramento, CA: City Code Section 45.102]

It is hereby declared a public nuisance for any person owning, leasing, occupying, or having charge of any premises in the City of Visalia which has one or more Oak trees located thereon to intentionally, negligently, accidentally, or otherwise maintain said premises in such a manner so as to cause harm to and of said Oak trees, by reason of any of the following conditions.

1. Water saturation or deprivation;

2. Nailing, screwing, stapling, bolting, or otherwise attaching boards, fences, signs, placards, posters, or any other material which might cause injury to the Oak tree;

3. Neglect in the pruning or trimming of overgrown, diseased, decaying, dead, or rotting limbs, branches, and foliage.

[Visalia, CA: Ordinance Code Section 2356]

Notes: Communities vary in the detail to which they prescribe the procedures which must be followed for nuisance abatement and assessment of associated costs. Notification and appeal procedures may be simple or involved.

... upon a determination by the Park Superintendent that such a private tree constitutes a public nuisance, he shall give written notice to the owner of the property upon which said nuisance exists to trim, remove, or otherwise control such tree in such a manner as will abate such nuisance. Failure to comply with such written notice within ten days thereafter, is a violation of this section...

[Patterson, CA: City Code Section 12.16.120]

... The City may remove or trim such tree, may permit any public utility to do so, or may require the property owner to remove or trim such tree on private property or on a public parking strip abutting upon the property of the owner. The failure of the property owner, or his duly authorized agent, to remove such tree after fifteen (15) days notice by the City Superintendent shall be deemed a violation of the provisions of this chapter, and the City Superintendent may then remove or trim such tree and assess the cost thereof against the property.

[Fowler, CA: City Code Section 7-1.08]

Purpose: To improve care of private trees by ensuring that firms performing tree maintenance are qualified and have appropriate liability insurance coverage.

Notes: Improperly performed tree maintenance work, including pruning, cabling, and removal, can cause property damage and endanger public health and safety. Therefore, many community tree ordinances require that firms engaged in tree work carry liability insurance.

Any person, firm or corporation engaged in the business of removing City trees shall carry public liability and property damage insurance in an amount to be determined by the city council and policies or certificates thereof shall be filed with the city clerk. Where deemed advisable, the Director may require the posting of a performance bond pursuant to Chapter 2.17 of this code to guarantee the completion of any job in accordance with adopted City Standards, rules and regulations.

[Carpinteria, CA: City Code Section 12.28.240]

Many jurisdictions require proof of insurance and professional qualifications only of firms performing work for the local government. Others, as shown below, extend insurance requirements to all tree service firms operating within the community.

Any person engaged in the business of pruning, trimming or removing of trees in the City of Escalon, shall secure an annual permit to so from the City Administrator. This permit is in addition to all other business licenses required by Ordinance No. 24 as amended of the City of Escalon. ... As a condition to obtaining said permit, the person shall furnish satisfactory proof to the City Administrator that he has public liability insurance covering said pruning, trimming, or removing trees, in minimum amounts ... as established by the Council by resolution. The policy or policies of insurance, or certificates thereof, shall be filed with the City Administrator, prior to the issuance of said license, and such person shall keep said insurance in full force and effect during the term of the permit.

[Escalon, CA: City Code Ordinance 147 Section 12]

Furthermore, improper pruning practices can irreparably disfigure and harm trees. In the interest of protecting community tree resources, it is reasonable for the local government to require proof of professional competence from those performing tree work for hire. Such proof might take the form of certification from the International Society of Arboriculture, completion of course work and training in arboriculture, passing an examination, or other criteria.

When the city requires tree pruning, any tree service contractor performing work shall have on its staff an arborist certified by the Western Chapter of the International Society of Arboriculture. This arborist must oversee all pruning work and certify that all work meets the city's pruning specifications. If a certified arborist is not on the staff of the tree contractor, the city arborist must approve the tree service contractor before work begins.

[San Luis Obispo, CA: Municipal Code Section 12.24.160]

As part of the license requirement, the local government can also require that tree care firms abide by the requirements of the tree ordinance and by tree care standards incorporated by reference in the ordinance, as in the following example.

It shall be unlawful for any person who is being paid a fee for the business of planting, cutting, trimming, pruning, removing, or otherwise modifying trees within the City of Myrtle Beach to conduct such business without first signing an affidavit stating that he/she has received and read the Tree Protection Ordinance and [most recent] ANSI A300 Standards [and that all work performed will consistent with these documents]. Such affidavit shall be completed and submitted when making application for or renewing a City of Myrtle Beach business license.
...

Tree pruning shall be accomplished in accordance with the procedures set forth in the [most recent] ANSI A300 standards.

[Myrtle Beach, SC: Municipal Code Section 903.4, 903.12.1]

The example code below requires tree care licensing, authorizes the city arborist to manage and enforce the licensing program under the review of the city tree commission, and requires licensees to abide by city standards and ordinances.

It is unlawful for any person or business to perform tree pruning and repair work (as defined in Section...) for hire within the city without a valid tree care license issued by the city arborist. Each tree pruned or otherwise modified in violation of this provision shall constitute a separate offense. The first such offense is punishable by a fine not to exceed $500; each subsequent offense is punishable by a fine not to exceed $1000 dollars. No maximum fine is established for multiple violations by a single person or business.

The city arborist is authorized to issue tree care licenses to persons or businesses that meet the following minimum requirements:
1. The person or at least one person on the staff of a business must be designated as a Qualified Arborist by the city. To be designated as a Qualified Arborist, a tree service employee shall demonstrate a knowledge of proper arboricultural techniques by providing documentation of professional certification, education, and/or experience acceptable to the city arborist.
2. The licensee must sign an affidavit to certify that all tree work will be performed under the direct supervision of the Qualified Arborist and will comply with all city standards and ordinances.

The city arborist is authorized to suspend or revoke the tree care license of any person or business that performs work which does not comply with tree care standards as specified in this chapter and in the comprehensive tree management plan. License suspensions and revocations may be appealed to the city tree commission within 10 days of notification. The decision of the city tree commission shall be final and is not subject to appeal.

The city arborist may reissue any tree care business license previously revoked subject to the above minimum requirements and any additional requirements as may be prescribed by the city arborist and approved by the city tree commission.

[Example code by the authors]

29. Harming public trees forbidden

Purpose: To prohibit negligent or intentional damage to trees and other plants growing in the public right of way.

Notes: This is one of the most common provisions in street tree ordinances. It is primarily targeted at preventing vandalism and negligent damage. Some ordinances have elaborate lists of many different ways which trees can be harmed. Others include prohibitions against fastening animals to trees and allowing animals to browse trees. Some ordinances extend protection to tree guards or supports as well as to trees. If damage is properly defined in the definitions section (see provision 4), it may be possible to cover all types of damage rather simply, and avoid long (and often incomplete) litanies of damaging practices. Legal staff should be consulted in this regard.

It shall be a violation of the provisions of this Chapter for any person to abuse, destroy or mutilate any tree, plant or shrub in a public parking strip or any other public place, or to attach or place any rope, wire (other than one used to support a young or broken tree), sign, poster, handbill or other things to or on any tree growing in a public place, or to cause or permit any wire charged with electricity to be placed or attached to any such tree, or allow any gaseous, liquid or solid substance which [is] harmful to such trees to come in contact with their roots, [trunks,] or leaves.

[Corcoran, CA: City Code Section 2-4-9]

Purpose: To provide for municipal review and approval of any activity which could be detrimental to public trees.

Notes: In order to safeguard the public investment in street trees and other public trees, many local governments reserve the right to regulate a variety of potentially damaging activities. The authority to approve regulated activities should normally be vested with the tree program manager. Each community needs to decide what activities it will regulate. Some of the activities that might require a permit include:

A. No person, unless expressly authorized hereunder, shall plant, remove, cut, trim, or prune, any street tree or any tree, plant, or shrub in a city park or other public place without a permit issued by the Director of Public Works. Such permit application shall be made at least 2 working days before the intended activity. The Director of Public Works may grant the permit or grant a permit on conditions when such is consistent with the provisions of this chapter, the Master Street Tree Plan, and other applicable laws and public policy. No such permit shall be valid for a period greater than 30 days after the date of its issuance.

B. In the case of moving a building along a street, such permit conditions may include rerouting, segmenting of such structure, and payment by applicant of attendant costs attributed to trimming or cutting authorized under such permit.

[Pasadena, CA: Municipal Code Section 8.52.080]

(a) The director shall issue permits to property owners to perform maintenance on or to remove city street trees, only if the following conditions are met:

(1) The property owner has established, to the director's satisfaction, that there is need for the proposed work on the tree; and
(2) The property owner has established, to the director's satisfaction, that the persons who are to perform the work are qualified to do so; and
(3) The director, in his sole discretion, has determined that any potential detriment to the city street tree population entailed by the proposed work, is justified in the individual case. In making this determination, the director shall consider factors such as the probability that the proposed work will destroy or seriously injure the tree, the tree's health, the desirability of that species as a street tree, whether the tree's condition and size threaten serious damage to property, the condition and number of other city street trees in the vicinity, whether there are other less onerous means of accomplishing the applicant's goals, and other related criteria.

(b) All work performed on city street trees pursuant to a permit issued by the director under this section shall be done within a sixty day period from the issuance of said permit, or within such longer period as the director shall specify.

(c) The director shall condition any permit granted pursuant to this section for the removal of a city street tree, on the permittee removing, and where the director determines to it be appropriate, replacing the tree. In such case, the full cost of removal and replacement shall be borne by the owner and such service shall not be provided by the city.

(d) The director may condition any permit granted pursuant to this section on any such conditions as the director determines to be necessary.

(e) The provisions of Sec. 45.12 shall be complied with whenever a property owner seeks a permit to remove or trim a city street tree to facilitate moving any building or other structure.

[Sacramento, CA: City Code Section 45.7]

As part of the procedure for granting tree removal permits, some communities require that a notice be posted or published in the newspaper.

The city shall post a sign notifying the public of the date and description of a proposed tree removal. The sign shall be posted in a prominent location, visible from a public street, for a period not less than five days before either staff consideration of a tree removal permit or a public hearing on a related development.

[San Luis Obispo, CA: Code Municipal Code Section 12.24.180F]

In some communities, local public utilities may be given a yearly permit that allows them to prune public street trees. In such cases, the local government should set minimum pruning standards and provide for inspection to enforce these standards.

When maintaining street trees, a public utility must observe good arboricultural practices, as specified by the International Society of Arboriculture Western Chapter Pruning Standards and the City of San Luis Obispo Safety Pruning Specifications.

[San Luis Obispo, CA: Municipal Code Section 12.24.140]

...Public utility companies subject to the jurisdiction of the California Public Utilities Commission may perform such pruning as is necessary to comply with the safety regulations of said commission and to maintain a safe operation of their facilities without a permit. However, they shall notify the planning department at least three working days (except in emergencies) prior to taking any action. The planning director shall cause such pruning work to be inspected, when appropriate, to insure that good pruning practices previously referenced are followed. The planning director shall have the authority to stop any tree-pruning performed by a utility if such practices are not being followed...

[Corte Madera, CA: City Code Section 15.50.040]

Purpose: To protect designated individual trees on private property from indiscriminate removal and damage.

Notes: This type of provision is typically known as a heritage or landmark tree protection provision. It is best suited to protecting conspicuous individual trees that are of unique historical, ecological, or aesthetic value, and therefore constitute an important community resource. A mature tree is a significant community resource that required many years to develop and can provide community benefits for generations, but can be destroyed in as little as a few minutes. This is the main reason that trees may be provided a higher level of legal protection than is usually afforded to other plants in the urban landscape.

Although trees can be long-lived, the life spans of individual trees are still limited, especially in the urban environment. Hence, this type of provision may not address the long-term sustainability of the urban forest. Furthermore, because of its focus on individual trees, this type of provision may not be appropriate or effective for protecting woodlands and forests. Woodland or forest conservation is addressed in provision 32 (Conservation of forest and woodland resources during development).

Provisions that regulate private trees are unlikely to be effective without community support. Unless residents strongly support tree protection, it is probably advisable to link tree protection with some sort of benefit or incentive to balance the additional burden imposed by the provision. The local government might provide tree care assistance, consulting, reduce certain assessments, or institute a recognition program to provide a tangible benefit to owners of protected private trees. Education and incentive programs are needed to ensure that protected trees are seen as an asset rather than a liability.

Classes of trees protected. Private tree protection regulations are commonly directed toward desirable, long-lived locally native trees and/or trees of historical significance. Most commonly, protected trees are designated by species, size, and/or location, although other criteria may also be used (see Defining special trees: heritage, historic, and landmark trees). These criteria should takes into account differences between species and the influence of local environmental conditions on tree growth rates.

One disadvantage of using a size criterion is that some property owners may elect to remove trees before they grow large enough to come under the protection of the ordinance. This is obviously a counterproductive situation, since it has the effect of destroying future tree resources. Unfortunately, this behavior has been observed in various communities. If the goal of the community is to protect woodlands or forests, rather than individual trees, a forest/woodland protection provision (see provision 32) may be more appropriate. In some communities, both types of provisions may be needed to address the range of situations involved. If both individual tree and woodland protection provisions are used in the same ordinance, ordinance language must be clear as to which provision applies to a given tree or group of trees.

Some communities apply tree protection provisions only to commercial properties by exempting single-family residential parcels. This may greatly limit the impact of the provision because most of a community's trees are typically located on residential parcels. On the other hand, if tree loss and poor tree care in commercial districts are serious problems in a community, focusing the provision on those problem areas may be appropriate.

In the following example, the various classes of protected trees are clearly stated. Another example is included on the Defining special trees: heritage, historic, and landmark trees page. It is important to grant protected status to trees planted or retained in compliance with the ordinance to establish a basis for long-term protection of tree canopy.

The city hereby declares that the following are protected trees:

(1) Trees planted or retained to meet the Landscape Ordinance (Section 910) requirements;

(2) Wax Myrtles (Myrica cerifera) and Crape-Myrtles (Lagerstroemia indica) designated as "tree forms" or used to fulfill tree requirements on approved landscape plans or greater than 10 feet in height;

(3) Any tree over 3" caliper located on city-owned property including any public right-of-way;

(4) Any Sycamore (Plantanus occidentalis) and Sweet-Gum (Liquidambar styraciflua) with a 12" DBH or greater;

(5) Any Pine (Pinus) with a 18" dbh or greater (except Japanese Black Pine with a caliper of 2" or more);

(6) Indigenous trees, as defined in 903.3(12); and

(7) All other species of trees that are 5" or more in caliper.

[Myrtle Beach, SC: Municipal Code Section 903.5]

Especially in urbanized areas, established trees are commonly threatened whenever property ownership changes. New property owners often do not understand or appreciate how trees on the property function in the landscape. In their zeal to make their mark on their newly-acquired properties, new landowners may quickly remove or inappropriately prune trees, or undertake landscape renovation projects that seriously damage tree roots and lead to the decline of established trees. If trees on only a few parcels each year are impacted by zealous but uniformed new owners, the cumulative effect on the community's mature tree population can be substantial.

The tree protection provision could be used to help reduce unnecessary tree damage by new property owners. The ordinance could extend protected tree status to virtually all trees on a property that has just changed ownership for a limited period, preferably at least one full year. By living with a tree for a full year and seeing how it functions in the landscape, property owners can make better decisions about managing the trees that have been passed down to them by previous owners. Furthermore, establishing a temporary moratorium on tree removal and other damaging activities provides a window of time during which the local government or a community tree group could try to educate new owners about tree values and proper tree tree care.

Protected trees shall include...

All trees with a caliper of one inch or greater (measured 4.5 feet above grade) on properties for which a change in ownership has been recorded within the previous 15 months.

[Example code by the authors]

Many tree protection provisions also provide specific exceptions that are not covered by the ordinance, as in the following example.

b) Exemptions. A permit is not required to cut or remove a tree(s) under the following circumstances:

(1) Trees that do not exceed two inches (2") in diameter when measured at a point four and a half feet (4.5') above the tree's natural grade.

(2) Trees damaged by thunderstorms, windstorms, floods, earthquakes, fires or other natural disasters and determined to be dangerous by a peace officer, fireman, civil defense official or code enforcement officer in their official capacity. The Department of Planning and Community Development shall be promptly notified of the nature of the emergency and action taken.

(3) When removal is determined necessary by fire department personnel actively engaged in fighting a fire.

(4) Trees planted, grown and/or held for sale as part of a licensed nursery business. This exemption is limited to trees with main trunks under ten inches (10") in diameter.

[Thousand Oaks, CA: Municipal Code Section 5-14.04]

A potentially adverse impact of a rigorous tree protection provision is that property owners may be discouraged from planting "temporary" trees for fear that they will later be restricted from removing these trees. "Temporary" trees may be used in the landscape for several legitimate reasons. For example, fast-growing, less desirable trees may be planted to provide shade or visual screening over the short term while more desirable, slower-growing "permanent" trees are developing. Also, areas may be overplanted to achieve more rapid screening or cover. Extra trees in such dense plantings often require thinning at some point to reduce competition between trees and promote good growth. In order to encourage tree planting on private property, it is reasonable to allow an owner to remove any tree on their property that they had planted of their own volition.

Any trees that exceed two inches in diameter when measured at a point four and a half feet above the tree's natural grade shall be exempt from the protection requirements of this ordinance (Section...) under the following circumstances:

(1) The property owner provides evidence acceptable to the Director that the tree has been planted by the owner during the period of his or her ownership of the property, and that the planting was not required by the city under Sections.... Evidence may consist of dated photographs, dated receipts, and/or other documentation acceptable to the Director. At the Director's discretion, the Director or authorized agent may inspect the tree to verify information provided by the property owner.

[Example text by the authors]

Activities subject to regulation. In many jurisdictions, protection of trees on private property is limited to situations involving development or construction on a parcel. In these situations, tree protection is tied to the issuance of construction-related permits, a process over which the local government can readily exercise some control . However, if protection is provided only during construction, long-term tree survival may not be guaranteed. In many instances, considerable efforts have been made to protect trees during the development process, including project redesign, only to have "protected" trees removed or seriously damaged by the subsequent property owner.

To avoid this pitfall, some communities extend protection generally to certain classes of trees whether or not construction permits are involved. In the following example, a permit is required to perform any activity that may damage protected trees. Relatively few local governments actually allocate the resources necessary to monitor and cite violators that illegally damage or remove trees on private properties. More commonly, such provisions rely on education of the public and are largely enforced on a complaint basis. Hence, such provisions normally require a high level of community support and voluntary compliance to be successful.

a) No person shall cut, remove, encroach in the protected zone, or relocate any oak tree on any public or private property within the City unless a valid oak tree permit has been issued by the City pursuant to the provisions of this chapter and the Oak Tree Preservation and Protection Guidelines. The status of limbs or trees as deadwood or dead trees must be confirmed by the City's Oak Tree Preservation Consultant.

[Thousand Oaks, CA: Municipal Code Section 5-14.04]

For the example above, the intended meanings of words such as "cut", "remove", "encroach", "protected zone" and "oak tree", should be defined in the definitions section (see provision 4). In this example, "cut" includes pruning. Poor pruning practices such as topping (a.k.a. "hatracking") may also be addressed in a separate provision (see provision 23).

Rather than requiring a permit for pruning, the city of Visalia, CA, requires filing of an "intent to prune notice". The purpose of this provision is to avert improper pruning of oak trees (see also provision 22 - Help for citizens performing tree maintenance):

Except in cases of emergencies as described in Section 2344, no person shall prune or cause to be pruned any Oak Tree limb of a diameter of 2" or greater within the City of Visalia without first submitting a completed Oak Tree Intent To Prune Notice with the Director, as provided herein.

[Visalia, CA: Ordinance Code Section 2345]

Criteria and standards for approving regulated activities. The criteria for approving tree removal or damage will vary somewhat between locations, due to the predominant tree species present or other site-specific details. The example below is typical of criteria used in many ordinances.

The intended decision of the Director shall be based upon reasonable standards, including, but not limited to, the following:

(a) The condition of the Oak Tree with respect to its general health, damage, status as a public nuisance, danger of falling, proximity to existing or proposed structures, interface with utility services, and its status as host for [parasitic] plant[s], pest[s], or disease[s] endangering other species of trees or plants with infection or infestations.

(b) The necessity of the requested action to allow construction of improvements or otherwise allow economic or other reasonable enjoyment of property.

(c) The topography of the land and the effect of the requested action on soil retention, water retention, and diversion or increased flow of surface water

(d) The number, species, size and location of existing trees in the area and the effect of the requested action on shade areas, air pollution, historic values, scenic beauty, and the general welfare of the City as a whole. (e) Good forestry practices such as, but not limited to, the number of healthy trees a given parcel of land will support.

[Visalia, CA: Ordinance Code Section 2342]

In the example above, the permitting authority essentially weighs various tree-related factors, such as tree health and growing conditions, potential hazard, and local environmental impacts, against the needs or desires of the property owner. Unfortunately, this can easily become a contest to see who has more clout - the property owner or the tree. More often than not, the tree loses the contest, largely because the tangible economic interests of the property owner (e.g., potential income, value of property improvements) are pitted against the less tangible and/or poorly quantified community-wide values provided by the tree (e.g., aesthetics, erosion protection, heat island mitigation).

Most heritage or landmark tree provisions set criteria for approving regulated activities such as tree removal, but few actually set minimum performance standards for approval. Although the criteria for approving regulated activities may be similar in many communities, appropriate performance standards will vary between jurisdictions. Standards should take into account factors such as the number and type of trees that are regulated by the ordinance, characteristics of the local community forest, and the amount of community support for tree protection. The following example sets standards for disallowing tree removal, but the use of terms such as "substantially alter", "reasonable accommodations", and "significant adverse effect" are vague and subject to diverse interpretations. Explicit minimum standards (e.g., "loss of more than 2.5% in property values") would be preferable.

Removal of trees - Conditions and exceptions

(1) Tree removal shall be disallowed in the following circumstances:
(a) Soil erosion or runoff problems will result due to topography, soil type, or proximity to flood plain or river protection areas; and the removal will substantially alter the existing soils adversely with regard to runoff and erosion. Information submitted by the City Engineer or other environmental specialist may be used by the Arborist in his evaluation.
(b) Specimen trees are located on site and cannot be adequately protected or replaced. Additionally, removal may be disallowed if reasonable accommodations can be made to alter the proposed project to save specimen trees and have not been made.
(c) Property degradation -- the removal will have a significant adverse effect on property values of any adjoining property. ...

(2) Exceptions. Tree removal from a site may be allowed if:
(a) The tree is located in an area where a structure or improvement will be placed and the tree cannot be relocated on the site because of age, type or size of tree.
(b) The tree is diseased or structurally unsound...

[Roswell, GA: Municipal code Article XIX, Section 1900.13 ]

Standards do not necessarily have to pose absolute limits on tree removal. They could serve to establish a set of thresholds; as each threshold is exceeded, permit requirements would become more stringent. A tiered system could provide an incentive for landowners to minimize the removal of protected trees. The example below illustrates how such standards might be established and related to the community benefits that trees provide. Minimum standards are explicitly stated in the example.

Requests for removal of protected trees shall be subject to the additional permit and mitigation requirements listed in Section... if any of the following conditions exist:

(1) Tree removal would result in more than a 25 percent reduction of the tree canopy cover on the subject parcel over the most recent three-year period.

(2) The ground slope within the drip line of the protected tree exceeds:
•15 percent for soils with a soil K value of 0.3 or greater;
•20 percent for soils with a soil K value less than 0.3.

(3) Tree removal would remove midsummer shade (as defined in Section ...) from more than 700 square feet of pavement or other nonvegetated improved surface.

[Example text by the authors]

The standards may also be listed in a separate document which is referenced in the ordinance as in the following example.

Not withstanding any of the other requirements of these regulations, it shall be unlawful to remove a specimen tree without the express written permission of the County Arborist or authorized agent(s). [The decision of the the County Arborist or authorized agent(s) shall be consistent with the] Administrative standards [that] have been established by the Director of the Department of Environment and Community Development for the identification, preservation and protection of specimen trees.

[Fulton Co, GA: Tree Preservation Ordinance Sec. I.V.C]

Most individual tree protection provisions are poorly suited to protecting groups or stands of trees because they lack performance standards that adequately account for the cumulative effect of tree loss. Evaluations are normally made on a tree-by-tree basis in individual tree protection provisions. If we look at any single tree closely enough, it is usually possible to find some reason to permit its removal - it may be relatively small, or in less than perfect condition, or located in an inconvenient portion of the parcel. By focusing on each individual tree, a heritage tree provision can allow a landowner or developer to "divide and conquer" a stand of trees, sometimes reducing a functional stand to one or two token heritage trees. Better protection of tree resources in wooded or forested areas can generally be achieved by utilizing strategies discussed under provision 32.

Permit process requirements. Permit applicants are normally required to provide the information necessary to decide if the proposed action meets the established standards for approval. Depending upon the criteria used to judge tree removal applications, this may include plot maps, data on tree size and condition, and the anticipated visual or environmental effects of removal. As a general rule, the information required should be limited to that which is needed to determine whether the permit should be granted and what mitigation (if any) should be required to offset the impacts of a permitted action. Many cities have standard forms listing the types of information to be submitted. Some communities exempt their municipal departments from the permit process, although this is not the case in the following example. Requiring city departments to meet the same requirements as private property owners assures more uniform implementation, and may provide beneficial public relations value as well.

Any person desiring to cut, move or remove a tree or protected tree within the city of Belmont shall apply to the Superintendent for a permit. A permit is not required for pruning as herein defined. The application for the permit shall be made on the form provided by the Superintendent for this purpose and shall include the number, location and type(s) of the tree(s) to be cut, moved or removed and the reason for such action. The applicant may submit an arborist's report or other expert evidence for consideration. The application shall be accompanied by any required fee to cover the cost of processing as set in the current City fee schedule. Fees shall be waived for applications made by a department of the City of Belmont on its own behalf.

[Belmont, CA: City Code Section 25-5]

While permit fees are normally collected from developers, some communities do not charge fees to homeowners who are required to get permits for pruning or removing private trees. This may help boost voluntary compliance, since homeowners may incur various costs simply to meet requirements for the permit application.

Many provisions that regulate tree removal during development require a report by a qualified professional on the condition of the trees. The professional may either be the city arborist or a qualified outside consultant. Because the applicant typically has a vested interest in removing trees that may conflict with development plans, a clear conflict of interest exists whenever an arborist or other consultant is retained by the applicant. The city or county can essentially eliminate such conflicts of interest by contracting for the services of any outside consultants that may be needed. The consultant is then responsible to and paid by the local government, which in turn recovers the charges from the applicant.

The permitting authority may also require the applicant to submit a tree condition report prepared by a qualified tree expert selected and retained by the City. The applicant shall reimburse the City for all costs related to the preparation of the report.

[Example text by the authors]

Some communities also include in this section a requirement that prior to removal, the tree be posted with a notice stating that the tree will be removed within a specified time, and describing the appeals process. Others require public notification before a permit is granted.

1. Tree Removal Notice Required. Except only as provided in Paragraph 10-11-4F5 of this Chapter, no Person shall cause or undertake any activity that anticipates or involves the actual or reasonably likely Damage or Removal of any Tree on a Lot that has a DBH greater than or equal to 10 inches without first having (a) been issued a valid Tree Removal Notice by the Village Forester pursuant to the requirements of Paragraph 10-11-4F2 and Paragraph 10-11-4F3 of this Chapter, and (b) displayed the Tree Removal Notice pursuant to the requirements of Paragraph 10-11-4F4 of this Chapter.

2. Tree Removal Notice Application. Any Person desiring, or required to obtain, a Tree Removal Notice shall submit to the Village Forester a Tree Removal Notice Application on a form provided by the Village.

3. Action on Tree Removal Notice Application. Within 72 hours after receipt of a Tree Removal Notice Application, the Village Forester shall approve the Tree Removal Notice Application and issue a Tree Removal Notice if the Village Forester determines that all of the information required by the Tree Removal Notice Application is true and correct. The Village Forester shall not approve or issue a Tree Removal Notice, if the Village Forester determines that the proposed activity constitutes a Regulated Activity. In such event, the regulations of this Chapter applicable to Regulated Activities shall apply in lieu of the regulations of this Subsection 10-11-4F.
4. Form and Display of Tree Removal Notice. At least 48 hours immediately prior to undertaking the activity for which a Tree Removal Notice is sought, the Tree Removal Notice shall be posted on the Lot on which the proposed activity is to take place in a manner so as to be clearly and prominently visible from at least one Public Right-of-way abutting such Lot.

[Lake Bluff, IL: Village Code Section 10-11-4F]

In the case of removal of any heritage tree...the director shall not act on such an application until a hearing is held thereon. Notice of the time and place of the hearing shall be posted in a conspicuous place on the real property upon which the heritage tree is located and shall be mailed to the applicant and all owners of real property within a five hundred (500) foot radius of the real property upon which the heritage tree is located...

[Sacramento, CA: City Code Section 45.217]

Conditions required for approval. Trees that are nominally "preserved" in the project design process can be lethally damaged during the construction phases of a project. Trees in constructed areas can be seriously damaged by alterations in the rootzone that destroy roots directly (e.g., trenching, lowering of soil grade) or indirectly kill roots by creating adverse soil conditions (e.g., addition of fill soil, soil compaction, impermeable pavement). Many publications have described how trees are damaged in the construction process and techniques for avoiding or minimizing damage through proper planning and construction techniques (e.g., Coder 1996a,b; Harris et al 1999, Johnson 1999, Matheny and Clark 1998, Schrock 1996, Sydnor, Sydnor and Heiligmann, WFC and Morgan 1989b).

To address this issue, some tree protection ordinances include specifics on how trees are to be protected during construction. However, details of tree protection in construction sites are highly technical and subject to revision and modification based on both local experience and new research. Site-specific tree protection specifications developed by a qualified professional are likely to be more effective than general "cookbook" standards. Hence, it is preferable to set a performance standard for tree protection in the ordinance but to avoid including the actual technical specifications. The provision should authorize the tree program manager to prepare, enforce, evaluate, and revise the actual specifications for tree protection. Although some communities have developed quite extensive tree protection guidelines which are separate from the ordinance itself, even highly detailed guidelines cannot substitute for a case-by-case analysis by a qualified professional.

...Tree protection shall comply with the guidelines in the Tree Protection Guide for Builders and Developers by the Florida Division of Forestry and any other reasonable requirements deemed appropriate by the Chief to implement this part.

[Jacksonville, FL:City Ordinance Sec.656.1207a]

Unless a site is carefully monitored throughout the entire construction period, damage inflicted to tree roots may not be apparent. Furthermore, aboveground symptoms related to root damage may not become obvious for a number of years after the damage is done. Some communities require developers to post performance bonds for trees that are to be retained so that the developer can be held accountable for tree damage that occurs during construction. A relatively long bonding period, preferably 5 years or more, should be used so that the impacts of construction on tree health can be adequately evaluated. The fact that a retained tree is still alive is not an adequate performance standard; performance bonds should not be released if retained trees show any decline in vigor or condition. In order to document changes in tree condition, tree ratings should be made prior to construction and shortly before the end of the bonding period.

Bonds, as required by this section, shall be in the form of letters of credit, certificates of deposit, cash bond, bonds issued by an insurance company legally doing business in the State of Florida, or other acceptable means agreeable to the city attorney. The letters of credit and certificates of deposit shall be drawn upon banks or savings and loans legally and actually doing business in Florida. Such bonds must meet the approval of the city attorney's office. This bond shall be in addition to any other bond required by any other governmental entity.

(1) Bonds shall be required for licenses involving the replacement of ten (10) or more trees, or the relocation of five (5) or more trees, or the relocation of any tree with a DBH of ten (10) inches or greater.

(2) Calculation for the amount of bonds shall be computed based upon the equivalent canopy replacement criteria applied to each street to be relocated or replaced, as provided in section 26-20 and upon the cost of installation and maintenance. The fair market value of the cost of trees that would be required to compensate for the canopy to be [relocated] or replaced shall be posted. The bond period shall be for the tree replacement performance period, as stated in the license or as extended or released, plus an additional sixty (60) days. The form of security shall be reviewed by the city attorney's office for legal sufficiency and may not be accepted until approved.

(3) Release of bonds:
a. Upon successful tree relocation and replacement as determined by this article and written approval by the city bonds required for tree relocation and replacement shall be released. Where possible, bonds shall be partially released for partially successful relocation/replacement projects, with the amount retained equal to the value of the additional replacement trees required, plus installation and maintenance.
b. Bonds may be released by the city when fee simple title is transferred. The city may condition the release of the bond upon the establishment of a new bond by the new owner in fee simple.

(4) Where the licensee plants fifty (50) percent more than the required number of replacement trees and establishes a suitable maintenance plan to ensure the viability of the replacement trees, the city may recognize the additional replacement trees as suitable security in lieu of a bond.

[Dania, FL:City Ordinance Sec. 26-25]

Compensation required for approval. The highest priority for a heritage tree provision is avoiding or preventing damage to or removal of protected trees. However, adverse impacts cannot be avoided, a local government may permit tree damage or removal under the condition that the applicant mitigates for the loss or damage. Mitigation generally comes down to the four basic options as shown below.

Mitigation method Location

1. Protect existing trees A. On-site

B. Off-site

2. Plant new trees A. On-site

B. Off-site

The mitigation may be carried out directly by the applicant as a condition of approval, or the applicant may be required to pay fees to the city or county in lieu of mitigating directly. In-lieu fees normally paid into a special account used for mitigation planting or protection and the local government becomes responsible for carrying out the mitigation. Some communities refer to to the use of in-lieu fees or off-site mitigation in general as tree banking.

Mitigation may appear to be a simple process, but as with many things, the devil is in the details. We explore a number of the options and issues in a separate mitigation page. If tree loss associated with urban development or other discretionary projects is substantial, the mitigation techniques used can have far-reaching consequences on the condition and form of the community forest. Hence, the community's long-term goals for its urban forest should be considered before determining how to structure the mitigation portion of this provision.

In many ordinances, a formula or standard is provided for calculating the amount of compensation that will be required for trees that are removed or injured. If planting of new trees is the mitigation method used, several different standards are commonly used to determine the amount of replanting that may be required. Common replanting standards include:

In some instances, it may be appropriate to use the value of the removed trees, as calculated from published tree appraisal standards (e.g., Guide for Plant Appraisal) as the replacement standard.

Typically, replacement plantings are required to be composed of the same species as those removed if native species are removed. For nonnative protected tree species, replacements must usually be selected from a list of approved species (or be approved by the city or county arborist or urban forester). In general, replacements are required to have the same mature size as the trees that have been removed, although the city/county arborist should have some discretion in this area to ensure that selected trees are compatible with the planting site.

Trunk caliper (diameter) is used as the standard in the following example, and mitigation standards are more stringent for removal of native live oaks.

(h) Protected trees identified for removal on the site clearing or tree removal permit application shall be replaced with new planted trees, unprotected trees or transplanted trees. Protected live oaks (Quercus virginiana) removed shall be replaced only with live oaks. The total caliper inches of replacement live oaks shall equal the total caliper inches of protected live oaks removed; for other removed protected trees, the total caliper inches of replacement trees shall equal one-third the total caliper inches removed, unless otherwise approved by the Chief. When there is significant loss of mature tree canopy or specimen trees on a particular site, the size [and/or number] of replacement trees may be increased by up to twice the minimum...by the Chief in order to compensate for that loss. If multi-trunked trees are used as replacement trees, then the total caliper of the four largest trunks shall equal the replacement caliper. New palms may be used only to replace protected palms removed. Replacement species used shall be approved by the Chief...

(1) New replacement trees shall meet the minimum standards for landscape materials established by [the administrative standards].

(2) Existing trees, two inch caliper or greater, which are not protected trees but which are preserved or transplanted, except those trees located in preserve areas, may be utilized to satisfy tree replacement requirements, subject to the conditions stated in ss. 656.1207 and 656.1213(b) and (d).

[Jacksonville, FL: City Code Section 656.1206]

The following example uses basal area as the replacement standard, and allows for the use of in-lieu fees if all required trees cannot be planted at the applicant's site.

(1) All protected trees removed in accordance with 903.8(1)c. through 903.8(1)h. shall be replaced in accordance with the following criteria. The replacement standards shall be listed on the permit...

(2) Any tree removed without a permit must be replaced with trees (not necessarily the same species) whose total basal area equals the basal area of the tree removed. All replacement trees shall be...considered required trees as part of a required landscape plan. As many trees as possible will be replaced [on the project site]. The tree(s) must be ... maintained in good health.

(3) When replacement of trees [on the project site] is not possible, the equivalent value of the tree as well as projected costs for installation and maintenance will be assessed by the Zoning Administrator and cash received from the property owner will be placed in the City of Myrtle Beach Tree Preservation Account for planting trees on public property.

[Myrtle Beach, SC: Municipal Code Section 903.10]

The example code below lays out a number of options for mitigating tree loss, including the use of in-lieu fees. These options provide the approving authority a high degree of flexibility in selecting appropriate mitigation.

Prior to any tree removal, the applicant shall demonstrate through a Tree Protection and Replacement Plan, Sensitive Area Mitigation Plan or other plans acceptable to the Administrator that tree replacement will meet the minimum standards of this section.

(1) Replacement Required. A significant tree to be removed shall be replaced by one new tree in accordance with subsection (5)...

(2) On-Site Replacement. Replacement trees shall be planted on the site from which significant trees are removed unless the Administrator accepts one or more of the alternatives set forth in subsection (3).

(3) Alternatives to On-Site Replacement: When on-site replacement cannot be achieved, the Administrator may consider the following alternatives:

(a) Off-Site Tree Replacement.

(i) The number of replacement trees shall be the same as described in section 20D.80.20-080(1), Replacement Required. Replacement costs (material plus labor) shall be at the applicant's expense.

(ii) Allowable sites for receiving off-site replacement plantings

(A) City owned properties identified on...[list of maps];

(B) Other City or County-owned open space areas, native growth protection areas (NGPA), or river and stream corridors within Redmond City Limits, or lands controlled by the City;

(C) Private open space which is permanently protected and maintained, such as a native growth protection area (NGPA).

(iii) All trees to be replaced off-site shall meet the replacement standards of this section.

(b) Tree Replacement Fee. A fee in lieu of tree replacement may be allowed, subject to approval by the Administrator after careful consideration of all other options. A tree replacement fee shall be required for each replacement tree required but not planted on the application site.

(i) The amount of the fee shall be the Tree Base Fee times the number of trees necessary to satisfy the tree replacement requirements of section 20D.80.20-080. The Tree Base Fee shall cover the cost of a tree, installation (labor and equipment), maintenance for two years, and fund administration.

(Ii) The fee shall be paid to the City prior to the issuance of a Tree Removal Permit.

(iii) A separate account shall be established by the City for fees collected. Tree Replacement fee receipts shall be earmarked specifically for this account. Funds withdrawn from this account shall be expended only for the planting of new trees in City owned parks, open spaces or rights-of way.

(c) Landscape Restoration. Where appropriate, the Administrator may consider other measures designed to mitigate the loss of trees by restoring all or parts of the forest landscape and its associated benefits. Measures may include, but are not limited to:

(i) Creation of wildlife snags from trees which would otherwise be removed;

(ii) Replacement of certain ornamental trees with native shrubs and groundcover;

(iii) Replacement of hazardous or short-lived trees with healthy new trees more likely to survive;

(iv) "Daylighting" and restoration of stream corridors with native vegetation;

(v) Protection of non-significant trees to provide for the successional stages of forest development.

[Redmond, WA: Municipal Code Section 20D.80.20-080]

Monitoring of protected trees and mitigation areas. A shortcoming that exists in almost every tree protection ordinance that we have reviewed to date is the lack of a long-term monitoring element. In general, after construction is completed or after a short bonding period (usually two years or less), no further follow-up is required for protected trees or new plantings . The city or county may have no further recourse if protected trees or replacements subsequently decline and die as a result of inadequate protection measures during construction, poor maintenance during or after the bonding period, or removal by new owners. Without continuing efforts to monitor protected trees, a community can continue to lose tree canopy over time even though many trees have nominally been protected or replaced.

We have recommended that all tree ordinances contain a provision to require that ordinance performance be assessed regularly (see provision 13). However, an additional monitoring provision may be necessary as part of the tree protection code to ensure that the applicant can be assigned a fair share of cost of monitoring long-term compliance. In-lieu fees and other permit approval fees should be sufficient to offset long-term monitoring costs. Monitoring methods are described and discussed in part 3.

INSPECTIONS: The Village Forester shall, on a regular basis, conduct such inspections and surveys as are necessary to monitor the Trees in the Village and to determine the existence, nature, and extent of violations of this Chapter.

[Lake Bluff, IL: Village Code Section 10-11-15]

32. Conservation of forest and woodland resources during development

Purpose: To promote the conservation of functional forests and woodlands during development.

Key elements:

Notes: The purpose of this provision is to establish a process for conserving woodland and forest resources that is invoked when land use is intensified to the degree that a discretionary permit is required. A provision that seeks to conserve functional forest or woodland systems must at minimum include the following features:

Relatively few local governments have implemented woodland protection provisions to date, but interest in this approach has been increasing in recent years. Some communities have attempted to use individual tree protection provisions (see provision 31) to protect woodlands, primarily by lowering the minimum diameter for tree protection. However, these tree protection provisions usually lack the necessary features noted above, and as a result, they often do not provide for satisfactory woodland or forest conservation.

The state of Maryland has one of the most progressive forest protection ordinances, the Maryland Forest Conservation Act (Natural Resources Article Section Title 5, Subtitle 16) passed in 1992. The Act requires local governments with planning and zoning authority to develop a local forest conservation ordinance and program which is at least as stringent as that spelled out in state law. This allows for a certain degree of program alteration to suit the particular needs and desires of a community. Local programs are audited every two years for compliance with the standards and requirements of the state law. Failure to comply results in administration of the local program by the Maryland Department of Natural Resources until such time as deficiencies in the local program are corrected. According to Galvin et al, in the first 5 years after its enactment, the Forest Conservation Act was responsible for 22,508 acres of forest retention and 4,314 acres of reforestation compared with 12,210 acres of forest cleared as a result of development.

Regulated lands: There are three basic a approaches that can be used in developing woodland conservation ordinances. Ordinances may use one approach or a combination of these approaches to determine what areas should be subject to conservation and reforestation or afforestation standards.

Existing forest resources. In the first approach, only lands with existing woodland or forest resources are subject to the ordinance. This approach is most applicable in areas where current forest cover is at or near historical or potential levels. Establishing the resource baseline is a potential source of problems for this approach. Unscrupulous individuals may destroy or alter much of the resource prior to development in an attempt to avoid conservation requirements that would be invoked upon application for a discretionary permit. To encourage good resource stewardship prior to development, historical aerial photos can be used to establish the forest resource baseline.

Potential forest resources. In the second approach, regulated lands include all those that have current forest cover as well as those that historically supported forests or woodlands. This approach is especially applicable in areas where current tree cover is well below former levels and the community has the goal of restoring lost or degraded woodlands and forests. In areas where the historic vegetative cover includes both forest and non-forest vegetation cover types, a delineation of potential or historical woodlands and forests should be prepared. A technical assessment of soils, historical records and photos, and local vegetation types should be conducted to establish a base map of areas that did or could support woodland or forest cover. These non-forested areas and areas with existing forest cover would then be subject to reforestation and afforestation standards. This approach allows for conservation of both existing resources and restoration of lost or degraded resources while taking into account the different capabilities of lands to support forest cover. Minimum afforestation standards could vary by area to reflect the differing capabilities of lands to support tree cover. The use of both current forest baseline data and minimum afforestation standards discourages landowners from clearing lands prior to initiating the development process.

Universal application. In the third approach, regulations apply to all lands irrespective of current forest cover. In the Maryland Forest Conservation Act, all landowners seeking to intensify land use on nonurbanized lands are responsible for a given level of woodland or forest canopy whether or not their lands are currently forested. This approach is appropriate in areas where forest canopy cover was historically fairly uniform before being cleared due to logging or clearing for agricultural use or urban development. It may also be appropriate in areas with historically low levels of forest cover if the afforestation standards are set at levels that are readily attainable for virtually any parcel. Minimum afforestation standards included in this approach can provide a disincentive to clear land prior to development.

Regardless of the approach used, existing forests and woodlands should generally be subject to higher conservation standards than potential forest land because existing forests generally have much greater ecological value than a newly planted stand. The following examples are provisions that define what is considered to be current or potential forest or woodland. Forest or woodland types of special local concern may be specifically noted in this section.

This provision shall apply to all lands within the jurisdiction for which approval for a discretionary project is requested and for which any of the following conditions apply:

A. All areas with native trees and associated woody vegetation covering 10% or more of the ground surface as of (month/year), as determined from baseline aerial photography dated (date) on file with the Planning Division.

B. Areas that formerly supported native trees or other woody vegetation as shown on base maps on file with the Planning Division. Areas designated as former woodlands shall include lands used for agricultural crops or pasture and urbanized areas covered by structures or pavement at the time of the aforementioned baseline aerial photography for the purposes of this ordinance.

C. All areas within 100 feet of a perennial or intermittent stream as shown on base maps on file with the Planning Division.

The approving authority shall be authorized to determine whether the provisions of this ordinance apply to any portion of a specific parcel. The burden of proof that the provision should not be applied to a specific parcel shall be on the property owner.

[Example code by the authors]

(k) Forest. --
(1) "Forest" means a biological community dominated by trees and other woody plants covering a land area of 10,000 square feet or greater.

(2) "Forest" includes (i) areas that have at least 100 trees per acre with at least 50% of those having a two-inch or greater diameter at 4.5 feet above the ground and larger, and (ii) forest areas that have been cut but not cleared.

(3) Forest does not include orchards.

[Annotated Code of Maryland Sec 5-1601]

Regulated activities: Activities regulated through the permit process should include any that could potentially degrade the woodland. This would include activities such as clearing the understory, or altering watercourses.

Except as provided for herein, no person or corporation shall destroy or significantly alter any forest or woodland through tree damage or removal, clearing, grading, tilling, burning, application of chemicals, or any other means unless they possess a valid Woodland Alteration Permit. No person or corporation shall be granted a permit for subdivision, grading, building, or the construction of any improvement on wooded or forested lands unless they possess a valid Woodland Alteration Permit. Any alteration of wooded or forested lands shall conform to the conditions and specifications of the Woodland Alteration Permit.

[Example code by the authors]

On tracts of commercial timberland, state forestry regulations may apply and often take precedence over local ordinances. In California, for example, the Forest Practice Act (California Public Resources Code Section 4511 et seq.) may apply to parcels of commercial forest land larger than three acres. As amended, this act does not allow individual counties to adopt rules or regulations that are stricter than those provided for by the act. However, counties may recommend that the State Board of Forestry adopt additional rules and regulations to account for local needs.

The Maryland Forest Conservation Act applies to any public or private subdivision plan or application for a grading or sediment control permit by any person, local government, or State government unit on areas 40,000 square feet or greater. Exceptions to the Act are specified, and include commercial timber harvesting operations and agricultural uses, as long as they satisfy certain requirements spelled out in the exemptions.

Criteria and standards for approving regulated activities. Standards for tree retention and reforestation will vary with the type of woodlands or forests involved. Canopy cover and/or stocking rates (trees per unit area) are probably the most widely applicable ways of expressing these standards. In general, any type of development will result in more canopy loss on parcels with high levels of canopy cover than on parcels with low canopy cover. Therefore, it may be desirable to establish standards for canopy retention that vary with the baseline level of canopy. Foresters or other resource professionals familiar with local conditions should be consulted to help establish meaningful and appropriate standards.

The canopy cover baseline can be used to set both retention and reforestation standards. Parcels showing an increase in tree cover beyond the baseline could be allowed greater flexibility when developed. Parcels showing a loss in tree cover could be required to restock the woodland to acceptable levels before development could occur. This strategy helps to provide a strong disincentive for clearing prior to development. Property owners would protect their future options best by maintaining or increasing tree cover on their lands.

In the first example below, viable stands of trees are given priority over individual trees. However, protection for individual trees of special concern could also be obtained through provisions of a landmark tree provision (provision 31). If properly constructed, tree protection and woodland conservation provisions can complement each other to provide for more complete management of existing tree resources.

Canopy retention standards. The following table shall be used to determine the minimum amounts of woodland canopy that must be retained during development on wooded lands:

Canopy retention standard shall be the greater of Column A or Column B:

Baseline canopy cover	Column A	Column B
80-100%	.75 x baseline canopy cover	65% canopy cover
60-79%	.80 x baseline canopy cover	51% canopy cover
40-59%	.85 x baseline canopy cover	36% canopy cover
20-39%	.90 x baseline canopy cover	19% canopy cover
19% or less	1.0 x baseline canopy cover	--

Example: For 50% baseline canopy, the minimum allowable canopy after development would be the greater of Column A, (.85 x 50% = 42.5% canopy) or Column B, (36% canopy). In this case the minimum allowable canopy after development would be 42.5%.

Retention standards shall be applied to retain stands of trees and undisturbed woodlands in priority over individual specimen trees which will be incorporated into the development. No more than 10% of the canopy retention standard may be met by individual trees not included within designated woodlands.

Reforestation standards. In areas where tree removal, clearing, fire, or any other intentional or accidental canopy reduction has resulted in canopy levels below the baseline level, the standard for reforestation shall be set at 100% of baseline levels, except that no reforestation standard shall exceed 85% nor be less than 15% canopy cover.

[Example code by the authors]

In the preceding example, two standards (Columns A and B) are used to provide a smooth transition between the required retention levels. For example, the top baseline canopy class (80-100% canopy) requires 75% retention of existing canopy, the second baseline canopy class (60-79% canopy) has a slightly higher retention standard of 80%. With these ranges, a potential problem arises when the low end of one canopy class is compared to the high end of the adjacent class. The retention standard according to Column A for 80% baseline canopy is 60% canopy cover (.75 x 80%), but the standard for 79% baseline canopy (the next lower class) would be greater at 63% canopy cover (.8 x 79%). When Column B is used, this inconsistency doesn't arise and the percent canopy cover retained steps down as you drop in baseline canopy cover between classes (80% baseline = 65% canopy cover retained, 79% baseline = 63% canopy cover retained).

The Maryland Forest Conservation Act and local ordinances based on it establish standards for both retention of existing forests and for the afforestation or reforestation of lands in connection with development and certain other land use changes. For both situations, canopy cover standards vary by the land use classification rather than preexisting levels of canopy cover. The example code below establishes forest conservation thresholds by land use category. If tree removal exceeds the set threshold levels, more stringent mitigation requirements apply. This serves to provide an incentive to project planners to conserve canopy cover to at least the threshold level.

A. There is a forest conservation threshold established for all land use categories, as provided in Subsection B... The forest conservation threshold [is] the percentage of the net tract area at which the reforestation requirement changes from a ratio of 1/4 acre planted for each acre removed above the threshold to a ratio of 2 acres planted for each acre removed below the threshold. B. After reasonable efforts to minimize cutting or clearing of trees and other woody plants have been exhausted in the development of a subdivision or project plan...the forest conservation plan shall provide for reforestation, purchase of credits from a forest mitigation bank, or payment into the forest conservation fund according to ... the following forest conservation thresholds for the applicable land use category:
Category of Use	Threshold Percentage
(1) Agricultural and resource areas	50 percent;
(2) Medium density residential areas	25 percent;
(3) Institutional development areas	20 percent;
(4) High density residential areas	20 percent;
(5) Mixed use and planned unit development areas	15 percent;
(6) Commercial and industrial use areas	15 percent.
[Annotated Code of Maryland 08.19.03.01 Article VIII. Sec. 8.1]

Under this system, a parcel being developed for commercial use with 100% forest cover could remove 85% of the existing canopy cover (15% canopy cover remaining) and would remain above the threshold. In contrast, a parcel with only 20% forest cover could remove no more than one quarter of the existing cover to remain above the threshold of 15% canopy cover. Reforestation requirements would apply to both parcels. In this hypothetical example, if we assume both parcels to be 100 acres, the reforestation requirement would be 21.25 acres for the fully canopied site (1/4 x 85 acres of forest removed) compared to 1.25 acres for the site with 20% forest cover (1/4 x 5 acres of forest removed).

If areas with high levels of canopy cover or other sensitive resource areas are to be protected adequately, additional restrictions or modifications of the threshold limits may be imposed in certain areas. In the example below, different woodland or forest clearing threshold values apply in "limited development areas" and "resource conservation areas".

...c) For the alteration of forest and developed woodland in limited development areas and resource conservation areas, the following criteria shall be met:

(1) (i) Up to 20% of any forest or developed woodland may be cleared for development provided it is replaced on at least an equal area basis;
(ii) an additional 10% up to a total of 30% of the forest or developed woodland may be cleared if approved by the Office of Planning and Zoning, and if it is replaced, by at least one and one-half times the total area of disturbed forest or developed woodland;
(iii) all remaining forest or developed woodland shall be maintained through restrictive covenants or similar instruments that are recorded in the land records of Anne Arundel County; and
(iv) when an area for reforestation is not available on the site, the developer shall either select an alternative off-site location or shall pay a fee as provided in subsection (d) of this section;
...
(3) if there is no established forest on a development site, the site shall be planted to provide a forest or developed woodland cover of at least 15%;

(4) replanted or afforested areas shall be maintained as forest cover through easements, restrictive covenants, or similar protective instruments; ...

[Anne Arundel County, MD; Ord 66-99 section 2-314.]

On a more local scale, higher retention or reforestation standards may be applied to sensitive areas or critical resource areas within a parcel. Areas such as floodplains, streams and associated buffer areas, steep slopes or other highly erodible areas, and critical wildlife habitats may be slated for higher levels of protection than is provided for other forested areas.

(c) Priority for retention and protection.- The following trees, shrubs, plants, and specific areas shall be considered priority for retention and protection, and they shall be left in an undisturbed condition unless the applicant has demonstrated, to the satisfaction of the State or local authority that reasonable efforts have been made to protect them and the plan cannot reasonably be altered:

(1) Trees, shrubs, and plants located in sensitive areas including 100-year floodplains, intermittent and perennial streams and their buffers, coastal bays and their buffers, steep slopes, and critical habitats;
(2) contiguous forest that connects the largest undeveloped or most vegetated tracts of land within and adjacent to the site,
(3) Trees, shrubs, or plants identified on the list of rare, threatened, and endangered species of the U.S. Fish and Wildlife Service or the Department;
(4) Trees that are part of a historic site or associated with a historic structure or designated by the Department or local authority as a national, state, or local Champion Tree; and
(5)Trees having a diameter measured at 4.5 ft above the ground of
(i) 30 inches; or
(ii) 75% of the diameter, measured 4.5 ft above the ground, of the current State Champion Tree of the species as designated by the department.

[Annotated Code of Maryland Sec 5-1607]

Afforestation standards are set by the Maryland Forest Conservation Act and local ordinances based on it. Parcels that have less than the set minimum amount forest cover must be afforested to minimum levels if they are developed. Landowners that plan to develop in the future have an incentive to establish tree canopy on portions of their property that would not be affected by a future development. Section (d) in the example below provides an additional disincentive for "preemptive" clearing.

(a) The amount of afforestation required under this subtitle shall be determined according to the amount of existing forest cover as provided in this section.

(b) A site that has less than 20% of its net tract area in existing forest cover shall be afforested up to at least 20% of the net tract area for:
(1) agricultural or resource uses; and
(2) medium density residential uses.

(c) A site that has less than 15% of its net tract area in existing forest cover shall be afforested up to at least 15% of the net tract area for:
(1) institutional development uses;
(2) high density residential uses;
(3) mixed use or planned unit development uses; and
(4) commercial or industrial uses.

(d) If existing forest cover is cut or cleared on a site that is below the afforestation levels set forth in this section, the site shall be reforested at a ratio of two acres planted for every acre cut or cleared, and this reforestation shall be in addition to the afforestation required by this section.

[Anne Arundel county, MD; Ord 66-99 section 2-304.6]

In the example below, standards for approving regulated activities include provisions related to stand regeneration. Such standards may be necessary in areas where native tree species are not regenerating well under current stand management conditions.

Removal of oak trees in the areas outside of the North County Area Plan, ... shall be allowed only if the following purposes and standards are satisfied...

B. Standards:

1. The current Best Management Practices as promulgated by the University of California... shall be followed to maintain and promote regeneration of oak trees.

2. A representative sample of sizes, ages and species of oaks shall be retained with special emphasis placed on retaining saplings.

....

[Monterey County, CA: Code Section 16.60.050B]

Permit process requirements, conditions and mitigation required. Permit applicants are normally required to provide the information necessary to decide if the proposed action meets the established standards for approval. This section should clearly indicate the general classes of information to be submitted with the permit application. The community forester or approving authority should be authorized to prescribe the specifics of the type and format of required information. Types of information that might be requested include baseline information on the status of the resource before development, and information on the proposed changes and their expected impacts. This should include data on all components of the woodland, including tree resources, understory vegetation, wildlife, soils, and hydrology.

As noted in provision 31, consultants retained by the applicant have a de facto conflict of interest because the applicant typically has a vested interest in removing trees or otherwise minimizing requirements associated with resource protection. The city or county can eliminate the conflict of interest by directly contracting for the services of any outside consultants that may be needed. The consultant is then responsible to and paid by the local government, which in turn recovers the charges from the applicant.

Whenever development occurs around sensitive natural resources, the primary goal should be to avoid adverse impacts through a sensitive development plan. To promote woodland conservation, the plan should strive to maintain groups of trees in contiguous areas that function as a cohesive habitat. Development patterns that cluster development on a portion of the overall project area and leave wooded areas as dedicated open space provide one means for maintaining functional woodlands.

Compensatory mitigation should only be considered after all reasonable efforts have been made to minimize loss. Reforestation on- or off-site is one form of compensation, but a newly-planted forest or woodland does not have the same habitat value or ecological diversity found in a mature stand. Although reforestation should be promoted for long-term resource conservation, suitable mitigation of short-term impacts can best be obtained by requiring that equivalent quantities of developable land be reserved from development. Such woodland reserves should remain undeveloped at least until reforested areas attain the resource and habitat value of woodlands which were lost. It may be desirable to target certain critical areas for acquisition as permanent forest/woodland reserves through this process of "mitigation banking" (see also Mitigation and Tree banking).

1. Removal of more than three protected trees on a lot in a one year shall require a Forest Management Plan and approval of a Use Permit by the Monterey County Planning Commission.

2. The Forest Management Plan shall be prepared by a qualified professional forester, as selected from the county's list of Consulting Foresters. Plan preparation shall be at the applicant's expense.

The Director of Planning and Building Inspection shall prescribe the format and content requirements for the Forest Management Plan and maintain a list of qualified and acceptable foresters to prepare the Forest Management Plan.

[Monterey County, CA: Code Section 16.60.040C]

Requirements for approving Woodland Alteration Permits. Issuance of a Woodland Alteration Permit is contingent upon the following requirements:

1. A Woodland Conservation Plan for the subject property must be approved by the approving authority.

2. The level of canopy removal requested must not exceed that provided for in the Canopy Retention Standards.

3. All reforestation plantings required as a condition of approval must be installed at least one year prior to the issuance of the Woodland Alteration Permit, and must be approved as adequate after inspection by the approving authority.

4. All other requirements pursuant to county ordinances, the California Environmental Quality Act (CEQA), and other applicable local, state, and federal laws and regulations must be fulfilled.

[Example code by the authors]

Woodland Conservation Plan. The purpose of the Woodland Conservation Plan (WCP) is to establish specific methods to conserve existing and potential woodland resources during development. The WCP shall be prepared by a qualified natural resources consultant retained by the county, and the charges of preparing the WCP shall be borne by the applicant.

The WCP shall provide that a project meets the Retention and Reforestation Standards of this provision through any, or a combination, of the following methods or other methods acceptable to the approving authority.

1. Minimizing the extent of the development and siting it to avoid impacts on existing woodlands.

2. Clustering development on a portion of the project area to retain continuous stands of trees in the nondeveloped portion. Transfers of development density from nondeveloped portions of the project area may be allowed only if nondeveloped portions meet the criteria for developable land.

3. Providing for reforestation of equivalent sites within or outside of the project area that will not be subject to future development. Where reforestation is used to replace existing woodlands removed for development, estimated canopy cover 20 years after planting shall be used to calculate the equivalent canopy cover provided.

4. Public acquisition of title to or permanent conservation easements on developable lands with equivalent woodland resources located outside of the project area. Total area, canopy cover, woodland type, understory vegetation, wildlife habitat value, and other appropriate resource assessment criteria shall be considered in determining whether off-site resources are equivalent to those of the project site.

Methods that protect and enhance existing woodlands shall be given precedence over those that restore non-wooded lands. Protection of woodlands within the project area shall be given precedence over off-site acquisition. The location of off-site mitigation areas is subject to the approval of the approving authority.

[Example code by the authors]

As noted under provision 31 and discussed in the mitigation page, ordinances may provide that fees be paid to a special fund that is directly used to pay for woodland/forest restoration. This is the case for the Maryland Forest Conservation Act and local ordinances based on it, as shown in the example below. The provision provides for a fee that is based on the area of plantings that are required as mitigation. The Act provides a time limit for the Department (or local governments) to accomplish the reforestation and afforestation activities that the in-lieu fees are collected to fund. A specific time limit may provide a strong incentive to ensure that the responsible agency actually accomplishes mitigation projects. However, setting an arbitrarily short time limit could be counterproductive if it limits the time available to complete complicated land acquisitions, or forces reforestation to occur during unfavorable conditions (e.g., an extended drought). A flexible time limit may be needed to ensure that funds are spent efficiently. Note in the example below that the use of funds returned to the payer remain restricted, and can only be used for local tree planting projects.

(b) Contribution; rate. - ...if any person subject to this subtitle demonstrates to the satisfaction of the appropriated State of local authority that the requirements for reforestation or afforestation on-site or off-site cannot be reasonably accomplished, the person shall contribute money at a rate of 10 cents per square foot of the area of required planting to the Forest Conservation Fund.

...(d) Time period for reforestation or afforestation; return of funds. - (1) The Department shall accomplish the reforestation or afforestation for which the money is deposited within 2 years or 3 growing seasons, as appropriate, after the receipt of the money.
(2) Money deposited in the Forest Conservation Fund under subsection (b) of this section shall remain in the fund for a period of 2 years or 3 growing seasons, and at the end of that time period, any portion that has not been used to meet the afforestation or reforestation requirements shall be returned to the person who provided the money to be used for documented tree planting in the same county or watershed beyond that required by this subtitle or other applicable statutes.

(e) Management of Fund. - (1) Money deposited in the Fund under subsection (b) of this section may only be spent on reforestation and afforestation, including site identification, acquisition, and preparation and may not revert to the General Fund of the State.

[Annotated Code of Maryland Sec 5-1610]

Ordinances modeled on the Maryland Forest Conservation Act require that a forest stand delineation and a forest conservation plan be prepared prior to any approval of forest removal..

(a) A forest stand delineation shall be prepared by a licensed forester, licensed landscape architect, or qualified professional who meets the requirements stated in COMAR, § 08.19.06.01B.
(b) Each forest stand delineation shall:
(1) consist of a map and a narrative;
(2) be used to determine the most suitable and practical areas for forest conservation; and
(3) contain or be accompanied by:
(i) a topography map delineating intermittent and perennial streams, and steep slopes over 25%;
(ii) soil mapping units and narrative indicating soils with structural limitations, hydric soils, or soils with a soil K value greater than 0.35 on slopes of 15% or more;
(iii) forest stand data indicating species, location, and size of trees and showing dominant and CO-dominant forest types;
(iv) location of 100-year floodplains;
(v) information required by the Forest Conservation Technical Manual; and
(vi) any other information required by the Department to assist in its review. ...

[Anne Arundel County, MD; Ord 66-99 section 2-304.2]

(a)A forest conservation plan shall be prepared by a licensed forester, a licensed landscape architect, or a qualified professional who meets the requirements stated in COMAR, § 08.19.06.01B.
(b) (1) A forest conservation plan shall:
(i) give priority to retention of existing forest on the site; and
(ii) if there is an insufficient amount of existing forest on the site, provide for afforestation as provided in § 2-304.6 of this subtitle.
(2) If retention of existing forest at or above the forest conservation threshold established in § 2-304.5 of this subtitle is unfeasible, a subdivider shall demonstrate:
(i) that there are no available methods or techniques to implement forest retention at the forest conservation threshold;
(ii) why priority forests and priority areas, as determined by an evaluation of the forest stand delineation, cannot be retained; and
(iii) where afforestation and reforestation will occur, with preference given to replanting in the priority areas.
(3) If a subdivider demonstrates to the satisfaction of the Department that retention of existing forest is unfeasible, the forest conservation plan shall provide for:
(i) reforestation in accordance with the provisions of §§ 2-304.4 and 2-304.5 of this subtitle; and
(ii) afforestation in accordance with the provisions of §§ 2-304.4 and 2-304.6 of this subtitle....

[Anne Arundel County, MD; Ord 66-99 section 2-304.3]

Invoking state regulations may provide another possible avenue for addressing woodland or forest protection. In California, for example, the local government can trigger the review and mitigation requirements of the California Environmental Quality Act (CEQA) when a project will have a significant impact on sensitive and important natural resources such as woodlands. It may be useful to include provisions that clearly indicate under what circumstances an Environmental Impact Report (EIR) is required. This may require two steps. First, the provision should state under what circumstances tree removal or woodland alteration will be considered a "project" under CEQA and thus subject to review. Second, the provision can set specific thresholds for loss or disturbance of woodlands and forests that would be considered "significant" under CEQA, and therefore require the preparation of an EIR. Requiring the preparation of an EIR above a certain threshold may help dissuade applicants from automatically requesting the maximum amount of clearing provided for in the retention standards.