Level IV Accreditation

Level IV accreditation recognizes leaders of tree and plant conservation around the world.

Level IV arboreta feature a minimum of 500 labeled species or taxa, a commitment to collections of conservation value, substantial public educational opportunities, and staffed scientists contributing to collaborative research.

These institutions manage extensive and well-documented collections and serve as global leaders in tree-focused research, conservation, and public education.

Level IV arboreta are distinguished by their scientific research staff, exemplary conservation and science missions, substantial educational programs, and their large and labeled plant collections.

How to Become Accredited

To become accredited, submit documentation showing your organization meets the Level IV criteria below, along with your online application.

Level IV Criteria

An arboretum plan
A governing group
Paid management
A dedicated curator or curator-equivalent position
A dedicated staff for science and conservation
A labeled collection of at least 500 taxa (species, subspecies, cultivars, varieties, etc.) of trees and other woody plants
A collections policy
Sharing of plant collections data
Substantial educational and public programming initiatives related to trees or other woody plants
Collaboration with other institutions
Tree science, strategic planting, or conservation activities
Substantial and integrated woody plant conservation (ex situ and in situ)

Download a sample Level IV application.

Compare all four levels of accreditation.

Explore other resources to help with the application process.

Apply Online

When you’re ready, submit your application online. There is no fee to apply.

Once your completed application is submitted, ArbNet staff will review your materials. Decisions are typically made within four weeks.

ArbNet accreditation is free and valid for 5 years.

Level IV Criteria

The following criteria must be met and supported by documentation to achieve Level IV accreditation.

An arboretum plan
A governing group
Paid management
A dedicated curator, or curator-equivalent position
A dedicated staff for science and conservation
A labeled collection of at least 500 taxa (species, subspecies, cultivars, varieties, etc.) of trees and other woody plants
A collections policy
Sharing of plant collections data
Substantial educational and public programming initiatives related to trees or other woody plants
Collaboration with other institutions
Tree science, strategic planting, or conservation activities
Substantial and integrated woody plant conservation (ex situ and in situ)

Download a sample Level IV application.

Level IV Criteria

An Arboretum Plan

You must have an overall plan for the space you intend to care for. This can be a business plan, organizational plan, a strategic plan, a master plan, or another—any documentation that defines the purpose of your arboretum and your plan to continue caring for the plants within your arboretum can be accepted as an arboretum plan.

An arboretum plan must define:

The purpose and mission of the arboretum
Its audiences
The types of plants that are grown to achieve the arboretum’s purpose or serve its audiences
Provisions for the maintenance and care of the plants
Provisions for the continuing operation of the organization through time with a clear succession plan

Depending on your organization or institution, your arboretum plan will more likely come from the organization and you should then develop a mission statement as it specifically relates to being an arboretum.

Download an example of an arboretum plan.

A Governing Group

To be accredited, your arboretum needs a dedicated group of people that is committed to the care of your arboretum, following the arboretum plan, and ensuring the future of the arboretum and that the plan can be carried out beyond a single individual. This group is known as a governing group.

This governing group will affirm fulfillment of accreditation standards and authorize the organization’s participation with ArbNet as an accredited arboretum.

Examples of governing groups include committees, boards, and oversight groups.

Governance groups do not have to be solely dedicated to the arboretum specifically, but can manage the arboretum along with other broader organizational responsibilities.

Paid Management

Level IV accredited arboreta must have one or more arboretum employees who have job responsibilities that specifically include management or operation of the arboretum.

A Dedicated Curator or Curator-Equivalent Position

A curator, or a curator-equivalent employee, is focused on the care and development of the arboretum collection, and acts in accordance with the arboretum plan and collections policy.

A Dedicated Staff for Science and Conservation

Arboretum employees who have job responsibilities that specifically include scientific and conservation activities related to trees and other woody plants for the arboretum.

A Labeled Collection of 500 Kinds of Woody Plants

The core of an accredited arboretum is its collection of woody plants and trees.

For Level IV accreditation, an arboretum must have a collection of 500 or more different taxa (species, subspecies, cultivars, varieties, etc.) of trees or other woody plants that are labeled or mapped in some way that’s accessible or visible to the public.

Labeling and maps can be physical or digital. There are many different free labeling solutions available. Learn more about Labeling and Maps solutions to meet accreditation criteria.

All trees do not need to be labeled; just a selection of 500 species or taxa for easy public awareness.

A Collections Policy

A collections policy describes the development and professional management of the plants in the arboretum collection in accordance with standards developed in the public garden and museum fields with consideration given to the Saint Louis Declaration regarding invasive species.

Such a policy and related practices includes a rationale for holding the particular collections of the arboretum, and collections inventory and record-keeping practices.

See examples of collections activities.

Sharing of Plant Collections Data

Sharing data from your arboretum’s plant collections with networked collections databases, such as the BGCI Plant Search Database contributes to global research and tree conservation efforts.

Substantial Educational Events and Public Programming

Substantial, diverse, and recurring educational and public programming beyond the base level required for accreditation in levels I and II. Programs must be related to trees (e.g. tree identification, ecology, conservation, collections, or some other tree-focused aspect of the arboretum mission or master plan.

See examples of education and community engagement.

Collaborations with Other Institutions

Level IV accredited arboreta engage with other types of institutions to advance research and conservation practices at a broad scale.

Your organization must collaborate in some way with other arboreta or relevant organizations around trees or other woody plants, preferably with evidence of existing collaboration.

Examples of relevant institutions include:

Public gardens
Universities
Local governments,
NGOs
Student groups
And more

Examples of collaborations include:

Plant evaluations
Research projects
In situ or ex situ conservation projects
Educational programs
Exhibits
Public events
Interpretation
Collecting expeditions
Plant exchanges
Professional meetings
Co-authoring scientific research papers
And more

See a more expansive list of collaboration examples.

Tree Science, Strategic Planting, or Conservation Work

This work should include direct research or the facilitation of scientific activities beyond public educational activities, in which data are acquired to solve problems in tree science or tree conservation. Examples include conducting plant trials, habitat monitoring, detecting pests and diseases, hosting collections-based research projects, or conducting research in forest ecology, physiology, systematics, and seed and tissue banking.

See a list of collections activities examples.

Substantial and Integrated Woody Plant Conservation (ex situ and in situ)

(outside of the natural habitat, for example at the arboretum) and in situ (within the natural habitat of the species) conservation, is required for Level IV accreditation.

For more information see BGCI’s Integrated conservation of tree species by botanic gardens: A reference manual (Oldfield & Newton 2012), particularly Figure 1 on page 15 copied below:

Figure 1 from Oldfield & Newton 2012. Integrated plant conservation combines in situ (on-site) and ex situ (off-site) conservation approaches to support species survival. In situ conservation protects species in their native habitat, while ex situ conservation ensures plant material is available for research, horticulture, and education activities that ultimately support reintroduction efforts, to prevent species from going extinct. (Adapted from Kramer et al., 2011)

Collections and Ex Situ Conservation

Institutional capacity, stability, and commitment to hold and safeguard plants of collections or conservation value. In your application, you must describe specific collections of value and interest (i.e. endangered species, legacy cultivars, etc) and enter the percent of wild collected woody plants in your collection.

In Situ Conservation

Engage in conservation efforts and programs or initiatives that aim to support in situ conservation and/or habitat restoration for threatened tree species and/or ecosystems. In your application, you must list the species or ecosystems you are working with and explicitly state how your efforts contribute to the in situ conservation outcome for that tree or woody plant species.

Resources

Download a sample Level IV application.

Explore different kinds of Level IV accredited arboreta around the world.

View and download a summary of the accreditation for all levels I–IV.

Use ArbNet’s Arboretum Tool Kits to find specific advice on applying as:

A cemetery arboretum
A city arboretum
A school arboretum
A university arboretum

More accreditation resources are available online to assist with the application process.

Contact Arbnet

Contact the ArbNet staff to discuss your application and the accreditation process.

Email

arbnet@mortonarb.org

Phone

1 (630) 310-7013

Examples of Collections Activities

A collections policy and collections data sharing are required for Level IV accreditation through ArbNet, but participation in additional activities beyond that are optional.

This list is meant to provide inspiration and ideas for arboreta wishing to expand and advance their collections management.

A collections policy (covers records management, accessioning, deaccessioning, etc.)
Regular collections evaluation
Conducting or participating in woody plant evaluation trials
A staffed collections manager or curator
An herbarium
A seed bank
A plant exploration program
Collections conservation (holding and safeguarding plants of collections or conservation value on behalf of the collective interests of the profession, e.g., rare and endangered plants, legacy cultivars, etc.)
A woody plant nursery
A woody plant breeding program
Any accredited or officially recognized collection(s)
A collections strategic plan (develops and plans for the themes and direction of your collections—could be a standalone plan or part of your greater organization-wide strategic plan or expanded collections policy)

Examples of Education and Community Engagement Activities

The following lists include common types of activities, in generally increasing levels of scale and complexity, that arboreta can host to meet accreditation requirements and to use as inspiration to expand event and outreach initiatives to meet higher levels of arboretum accreditation.

On the digital ArbNet accreditation application, you will be asked to check all activities your arboretum participates in.

Open Public Access and Events

Annual tree events (Arbor Day, International Forestry Day/week)
Self-guided walking tours
Giving engagement and outreach presentations for other organizations and groups
Hosting conferences or similar events
Exhibitions and/or interpretive signage

Recurring Public Programming

Guided walking tours or tram tours
Docent training and opportunities
Conference (or similar venue) presentations
Course/class/workshop offerings
Hosting webinars/ seminars
Community/citizen science programs
Children’s garden
School programs

Extensive / Enhanced Educational Programming

Articulated engagement philosophy or interpretive plan with intended outcomes and assessment plan
Plant selection, care, and/or pest/disease consultation and support
Educational and outreach publications
Digital content—podcasts, online courses, social media outreach, etc
Ethnobotanical engagement (Indigenous knowledge content and co-creation with community partners)
Accredited educational or training programs
Internship opportunities
Summer/ seasonal camps

Urban and Community Forestry

Urban and community agricultural and food forest programs and projects
Environmental justice and tree equity programs and projects
Urban and community greening efforts
Supporting the creation of new accredited arboreta

Examples of Collaborations

Participating in professional, community, and organizational woody-plant related collaborations qualify an arboretum for level IV accreditation through ArbNet.

In your online application for Level IV accreditation, you will be asked to mark which of the following kinds of organizations your arboretum is engaged with.

Other arboreta and public gardens
Botanical garden associations or industry societies
Seed banks and other germplasm repositories
Conservation, restoration, ecological, and/or environmental organizations
Invasive species networks or organizations
Dendrology and/or forestry associations/societies
Arborist/arboriculture associations and professional societies
Indigenous peoples groups and organizations
Community groups and organizations
Universities and colleges
Schools and/or student groups
Government agencies
Nongovernmental organizations (NGOs)
Nature preserves and/or parklands
Plant, botanical, biological, and/or horticultural societies or associations
Garden clubs
Landscape architecture and design societies/ associations
Businesses (e.g. arborist or landscaping companies)
Zoos and/or aquariums
Professional societies or associations for zoos, aquariums, or wildlife
Museums
Museum societies/associations
Other organization types

Examples of Tree Conservation and Science

As part of your application for Level IV accreditation, you will be asked to check activities that your arboretum participates in related to tree conservation and scientific research.

Links and Acronyms

Global Conservation Consortia (GCC)

International Union for Conservation of Nature (IUCN) Global Tree Specialist Group

Botanic Gardens Conservation International (BGCI)

BGCI Conservation Action Tracker

Public Gardens as Sentinels against Invasive Plants (PGSIP)

General Capacity-Building for Threatened Tree Conservation

Promote tree conservation through your networks, conferences, presentations, social media, and arboretum website
Host or share GCC educational content (e.g GCC Species Steward panels and/or taxa information sheets; these are provided by the GCC Coordinators)
Carry out education/awareness raising and interpretation among your visitors for threatened trees
Host tree conservation conferences, training workshops, or related meetings (e.g. IUCN Global Tree Specialist Group meeting)
Contribute content, expertise, or other support to tree conservation training materials, such as guidance briefs, manuals, or reports
Host employee(s) who is an active member of the IUCN Global Tree Specialist Group
Report and share information on your tree conservation work using the BGCI Global Tree Portal, including the Conservation Action Tracker

Ex situ Tree Conservation

Enable researchers or conservationists external to your organization to use your grounds, collections, and/or resources for tree conservation and science work/research
Formal participation in an ex situ conservation project focused on threatened tree species (provide project name in part 7b below)
Partner with Indigenous communities to support culturally significant ex situ tree conservation and restoration activities
Participate in Public Gardens as Sentinels against Invasive Plants (PGSIP) by collecting and sharing data about plants escaping from cultivation in your arboretum
Share threatened tree germplasm/material with other institutions (e.g. for propagation, living collections, seed banks, herbaria, etc)
Develop protocols for propagation of threatened tree germplasm
Host and manage a native or threatened tree nursery
Undertake planting trials for threatened trees
Conduct conservation genetics research on ex situ collections of threatened tree species
Threatened trees included in your collection
Threatened trees included in your collection with interpretation aimed at conservation awareness
Conservation of legacy cultivars
Engage in collections climate change adaptation planning and activities
Provide support to other arboreta to improve their capacity to participate in threatened tree conservation activities (e.g. provide training, financial support, mentorship, threatened tree germplasm/seeds, etc.)
Host a metacollection site as a designated Species Steward for one of the GCCs

In situ Tree Conservation

Formal participation in an in situ conservation project focused on threatened tree species (provide project name in part 7b below)
Partner with Indigenous communities to support culturally significant in situ tree conservation and restoration activities
Participate in in situ expeditions and surveys to seek out and monitor threatened tree populations
Host and manage a native or threatened tree nursery to repopulate threatened tree species in situ
Conduct conservation genetics research on in situ populations of threatened tree species
Contribute to red listing initiative for trees within a taxonomic group or region
Lead red listing initiative for trees within a taxonomic group or region
Engage in or support in situ habitat restoration or habitat protection in support of priority threatened tree species or ecosystems (e.g. invasive species removal, land protection, reforestation, facilitating sustainable management planning)
Engage in or support in situ conservation and recovery of threatened tree species in the wild (e.g. population monitoring/surveys, reintroduction of seeds/seedlings, assisted migration)
Carry out conservation planning for threatened tree species, e.g. individual species recovery plans, or multi-species plans