Tohono Chul Living Plant Collection Charter
Mission & Overview
Mission
We are a community oasis where reverence for the cultural and natural ecology of the Sonoran Desert region inspires responsible stewardship so that future generations may thrive.
Vision
We envision a Tohono Chul that is:
• An ecological leader — championing actionable, nature-based solutions to the core environmental challenges facing arid lands.
• An immersive environment — celebrating the wonders of the Sonoran Desert.
• A commons — integral to the community, meaningfully engaging with the diverse histories and cultures of the region.
Overview
Tohono Chul’s history dates back to 1966, when Richard and Jean Wilson began acquiring parcels of land in the Sonoran Desert with the explicit goal of preserving its natural integrity. In 1985, their efforts culminated in the opening of a public garden, which expanded to its full 49 acres by 1997. This visionary initiative not only created a sanctuary for ecological appreciation but also became a cornerstone of environmental education for Tucson’s residents and future generations.
Today, Tohono Chul offers a diverse array of programs—including lectures, guided tours, workshops, concerts, and special events—all designed to deepen the love and understanding of the region’s natural and cultural heritage. Committed to enriching lives, Tohono Chul actively engages the Tucson community in exploring the wonders of the Sonoran Desert while promoting responsible environmental stewardship.
Purpose of the Living Collection Charter
The Living Plant Collection Charter establishes a comprehensive framework for the management and daily operations associated with the Living Collection at Tohono Chul. This Charter serves to support Tohono Chul’s overarching mission and vision by providing structured guidance and ensuring overall consistency in collection development. It encompasses various aspects of collection management, including the acquisition of living plants, curatorial and interpretive strategies, and the preservation and propagation of germplasm.
Collection Objective & Scope
Objective
Tohono Chul’s living collection advances our mission of being- a community oasis where reverence for the cultural and natural ecology of the Sonoran Desert region inspires responsible stewardship so that future generations may thrive. The selection and development of the plant collections at Tohono Chul are strategically aligned with the diverse horticultural needs of the garden. Plants are selected based on specific criteria including historical and cultural relevance, conservation value, proximity of natural range to Tohono Chul, display aesthetics, and educational benefit.
Scope
The Living Collection includes perennials, shrubs, trees, cacti, succulents, and seeds, housed within Tohono Chul’s seed bank, located in the core gardens and throughout the adjacent desert landscape of the 49-acre campus.
Plant species included in the Living Collection must meet one or more of the following criteria:
- Its Native distribution is found within the United States and Mexico Borderlands, including the Sonoran, Chihuahuan, and Mohave deserts.
- It is significant to the past, present and future of agricultural and cultural activities in the Sonoran Desert region.
- It provides mission-aligned educational benefits through public programming, interpretation, field studies and/or internships.
- It fulfills a display function that encourages and promotes responsible stewardship in the Sonoran Desert region by showcasing plant diversity, sustainable horticulture, and innovative landscape design.
- It is recognized as a species of significant taxonomic value, acquired for conservation purposes.
- Non-native plants must contribute to the emphasis and recognition of Sonoran Desert native genera and species.
Roles & Authority Over Collections
The Living Collection Charter is approved by the Executive Director, Director of Operations, and Garden Manager. The Living Collections Coordinator is responsible for drafting and updating the Charter. The Charter will be reviewed every five years to ensure its continued relevance and effectiveness. Implementation of the Charter is a shared responsibility among all staff members of the Gardens Department and the Arts & Engagement Department, as well as volunteers. Oversight is provided by the respective directors and managers to ensure adherence and successful execution of the Charter’s objectives.
Responsibility for the review and revision of the Living Collection Charter is shared among the Executive Director, Director of Operations, Garden Manager, and the Living Plant Collection Charter Committee. This committee includes the Living Collections Coordinator, Propagation Coordinator, Retail Nursery Coordinator, Community Engagement Manager, a representative from the Gardens Department, a volunteer representative, and external partners.
The Garden Manager has authority over the plant selection, acquisition, access and utilization of the living plant collection, including the categorization of plants based on established criteria. Any changes to the collection that are part of a larger garden design, redesign, or renovation project will be made in consultation with and approved by the Executive Director.
The Garden Manager and Living Collections Coordinator will make decisions regarding what plants to accession, and de-accession based on the aesthetic, design, educational, ecological, and conservation value of a plant, along with its overall health.
Access & Use of the Living Collection
The Living Plant Collection is accessible to the public during standard operating hours and special events, for observation, enjoyment, and educational engagement. Access to collection records and specific accession locations can be obtained through consultation with the Living Collection Coordinator.
Requests for the loan, transfer, or use of plants or other materials are carefully evaluated and approved by the Garden Manager. To initiate a request, stakeholders must complete the Living Plant Collection Access Request form and submit it to the Garden Manager for review. Upon approval, the recipient agrees to acknowledge Tohono Chul as the supplier in all reports and publications derived from the use of the plant material, including propagules, and to submit a copy of these reports and publications to Tohono Chul.
Priority consideration for requests is given to the following entities:
- Independent researchers and academic research institutions
- Public gardens
- Artists
- Indigenous peoples of North America
- Tohono Chul Partners
Acquisition
Record keeping of acquisitions is conducted to ensure that all plant material is trackable and that all current and future plantings align with Tohono Chul’s mission goals. Each accession must fulfill at least one of the criteria listed in the “Scope” section of this document. Plant material will be accessioned only after it has been planted on grounds or in a container. Annuals, invasive species, and sporadic seedlings will not be accessioned.
All acquisitions must include the following:
- Most current and accepted nomenclature
- Date of acquisition
- Accurate provenance information
- Current plant health
- GPS location
Methods of acquisition include purchase, exchange, donation, and collections from wild populations. Acquisitions can be received in the form of plant specimens and germplasm. All acquisitions must adhere to laws regarding wild collection, importation, and distribution across national and state boundaries. All material that is wild collected and imported across national and state boundaries must include the necessary permits and permissions. Additionally, material acquired from areas of federally recognized Indigenous land must include a written statement granting permission.
Plants can be purchased through Tohono Chul’s retail and wholesale vendors. All Plants acquired from vendors must meet the criteria outlined in the Living Plant Collection Charter.
Plants can be obtained through exchange with research institutions, public gardens, and other relevant institutions. Plant material received from peer institutions must comply with the specified criteria of the Living Plant Collection Charter.
Donations and gifts will be considered and approved by the Garden Manager. Tohono Chul stakeholders must submit a completed Living Plant Collection Donation Request Form to ensure accurate record-keeping, acknowledgment of specific terms of use, and proper transfer of ownership to Tohono Chul. All donations and gifts must meet the criteria outlined in the Living Plant Collection Charter to be considered.
Plants obtained through donations, gifts, and exchanges for the Garden’s Living Collection are subject to a health inspection and must be quarantined for a minimum of four weeks.
Deaccessions
Accessions may be deaccessioned from the Living Collection when they no longer fulfill Tohono Chul’s mission goals and garden function. Decisions regarding deaccessions will be made by the Living Collection Coordinator in consultation with the Garden Manager.
Deaccessioning live plants of high conservation value is restricted until suitable replacements are available. Plants of significant conservation value must be propagated, if material can be collected without negatively affecting the plant’s health, to ensure the continuation of their genetic lineage. Propagules of significant plants may be transferred to other public gardens and institutions to prevent the total loss of the plant.
Reasons for Deaccessioning plant material:
- It no longer pertains to the mission of Tohono Chul or specific garden design goals
- It is considered a safety hazard
- Absent or no longer in its mapped location
- Damaged or diseased
- Dead
- Duplicated
- Deemed invasive
- Garden locations from which diseased plants are removed will be monitored through the plant database (Hortis) to prevent the spread of disease to nearby plant material.
Request & Donation Forms
To donate or request loans, transfers, or use of plant material from the Living Plant Collection, please complete the applicable form to be considered.