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Biodiversity & Conservation

The concept of the conservation garden was developed at the North Carolina Botanical Garden (NCBG) in the early 1990s to represent the many conservation-related activities that were at the heart of the Garden’s mission and programs. This included propagating native plants to ensure that populations were not damaged by wild collecting, banking seed for reintroduction and protection against extinction, conserving habitats to preserve naturally occurring biological diversity, and creating gardens that display and demonstrate native biodiversity and sustainable gardening practices.

Ex Situ Conservation 

                                                            Garden plant collections policy includes plant conservation and biodiversity component

NCBG adheres to the collection policy of the Center for Plant Conservation (CPC) for rare, state- or federally-listed, and G1/G2 species. Many factors must be considered about the species’ biology, life history, and status in the wild, which are detailed in the 2019 CPC Best Plant Conservation Practices to Support Species Survival in the Wild. For example, the Garden follows the 10% rule to minimize impact on the wild population, by collecting no more than 10% (or the maximum allowed by permits) of an individual plant’s reproductive output and/or no more than 10% of the population reproductive output in a season in any one of ten years.

Garden regularly facilitates taxonomic verification of collections of conservation concern

NCBG is fortunate to administer the University of North Carolina at Chapel Hill Herbarium (NCU) – the largest and most comprehensive herbarium in the Southeast – the director of which is the foremost authority of native plants in the Southeastern United States. All collections use the most current taxonomy and are verified through herbarium staff.      

Garden supports recovery of native North American species

NCBG was founded on conservation principles and championed the concept of Conservation Through Propagation that promotes the use of native plants and conservation of wild populations. They were a founding Participating Institution of the CPC (in 1984) and Seeds of Success program (in 2006).

Taxa in living collection that are of conservation concern

The NCBG Rare Plant Garden is primarily meant for education, although there are some long-lived perennials that represent a curated ex situ conservation collection. The CPC National Collection contains three “exceptional species” that must be curated as a living collection.

Garden tracks threat statuses via a plant records database

Two NCBG staff are on the NC Plant Conservation Program (PCP) scientific committee, and one is on the board of directors. PCP is the state governing body that lists and protects rare plants and their habitats. NCBG is also the host of the NC Rare Plant Discussion Group – the annual state-wide gathering of botanists who help monitor/share the status of the states rare plants.

Garden prioritizes threatened species for ex situ preservation

NCBG works closely with the NC Plant Conservation Program – the regulating body of the state for rare plant conservation – and the NC Natural Heritage Program – that tracks the status of threatened species. These agencies direct their ex situ preservation efforts both through CPC accession and for their in-house efforts.

Genetic Diversity


NCBG documents and curates potential genetic diversity. The Garden uses comprehensive accession collection protocols – particularly for CPC and propagules intended for restoration projects. All seed accessions are well-documented for provenance and habitat characteristics including those collected for horticultural purposes.

The Garden also maintains, shares, and backs up genetically unique germplasm. The NCBG seed bank includes accessions for horticultural use, restoration purposes, and ex situ conservation collections. The restoration and ex situ conservation collections follow Seeds of Success and CPC protocols, respectively, that serve to maximize accession genetic diversity. They also share germplasm with other botanical institutions where there are mutual interests, and back up certain CPC collections at the USDA/ARS National Laboratory for Genetic Resources Preservation.

All germplasm used in reintroductions are collected to capture genetic diversity; and CPC accessions are collected and stored by maternal line to ensure that genetic diversity is maximized in rare plant reintroductions. Their guidelines use CPC Best Management Practices (for rare species) and the National Seed Strategy (for the more common species).  

Garden maintains collections of native/local plant material:

The Garden specializes in native, and local, plant material collections that includes oversight of over 1,200 acres of exceptional natural areas.

Living accessions of wild origin:

The vast majority of living accessions are of wild origin, and all have provenance documentation since 2009. Nearly all their 56 CPC species’ accessions have orthodox seeds and are therefore desiccated, vacuum-sealed, and frozen (at -180C).

In Situ Conservation 


Garden leads or participates in the following in situ activities:

  • Climate change mitigation: Through proper natural area management, the Garden works to ensure ecosystem health (including genetic diversity) that will ostensibly enable these plant populations to respond to climate change.
  • Invasive species management: A significant amount of effort is given to the control (and hopeful eradication) of invasive species in their nature preserves. Special consideration is given to their highest quality natural areas.
  • Population monitoring: Formalized demographic monitoring is conducted on all rare plant reintroductions and on those taxa the Garden has contracts with from the US Fish and Wildlife Service. Monitoring of restoration plantings is less formal and is typically done using photopoints. 
  • Restoration/management: The Garden has an active restoration/management program that includes an inhouse prescribed burning crew. A weekly volunteer group – the Green Dragons – provide considerable help in restoration and management activities.
  • Species reintroduction: The Garden has eight ongoing rare plant reintroductions and dozens of common species reintroduction/augmentation projects in their natural areas. They strive to use matched habitat.    

Garden uses science-based best practices for all in situ activities

All Garden Conservation Department staff have advanced degrees in botany/ecology and strive to include science-based best practices in all in situ activities. These staff also teach conservation science courses in the Garden’s Certificate Program in Native Plant Studies, attend and present at professional conservation meetings, and provide best management practices information to others. Attendance at professional meetings (such as Natural Areas Association, Center for Plant Conservation, and Association of Southeastern Biologists) gives them the opportunity to learn from others in our field and improve their practices (and confirm/validate best management practices).       

Garden uses appropriately provenanced plants or propagules for reintroduction and ecosystem restoration

All accessions are carefully documented (most with associated voucher specimens). Only regionally sourced plants are used in restoration, most of which come within a 30-mile radius of the restoration site or seed material from the most local population. All rare plant population augmentations use plant material from the receiving population.  

Garden obtains appropriate permissions and follows all laws governing use of plants or activities on property for in situ activities

The Garden works on sites that they administer or on sites with appropriate permissions and permits. They typically receive permits from the NC Plant Conservation Program, US Fish and Wildlife Service, NC Wildlife Resources Commission, NC State Parks, US Forest Service, National Park Service, The Nature Conservancy, and agencies in surrounding states.  

Garden maintains long-term monitoring of species and areas impacted by in situ activities

For rare plant reintroductions, the Garden has long-term monitoring protocols. They practice more qualitative monitoring of their in-situ management practices but do have a limited number of long-term permanent plots/transects. In the last few years, the Garden has partnered and trained students in certain university courses for tree inventories on their nature preserves. 

Garden incorporates climate change adaptation and mitigation when designing in situ programs

According to climate change models used by the NC Natural Heritage Program, the Piedmont ecoregion is not expected to have as severe effects as the mountains and coastal plain. The in-situ programs are therefore structured to create “healthy” populations and ecosystems that are both resistant and resilient to climate change effects. 

Garden supports recovery of native North American species

As a native plant garden, the in- and ex situ practices focus on the recovery of native North American species. The Garden also supports native plant recovery for other organizations and individuals by offering restoration seed and whole plants for their projects. Their Daily Plant Sale also offers dozens of locally adapted native plants for the home gardener, which we believe to be an important step toward converting the cultivated landscape to urban natural areas.     

Research & Plant Conservation Expertise

                                                                                                                                                         The Garden supports plant conservation and biodiversity research in these areas:

  • Alternative longterm storage – the Garden does not have tissue culture or cryopreservation facilities, but they do cooperate with others that do, such as the Cincinnati Zoo and Botanical Garden. 
  • Floristics – the Garden administers the University of North Carolina at Chapel Hill Herbarium (NCU) – the largest and most comprehensive herbarium in the Southeast – the director of which, Alan Weakley, is the foremost authority of native plants in the Southeastern United States. Dr. Weakley is the author of the Flora of the Southern and MidAtlantic States (from which the plant identification app, FloraQuest, was developed), lead author of the Flora of Virginia, and prepares “mini-floras” or “florulas” for other states in the Southeast. In addition to floras, several Herbarium Associates and graduate students directly contribute to the floristics of the Southeastern US.
  • Plant biology, ecology, or conservation genetics – Conservation Department and Herbarium staff conduct research projects, publish in peer-reviewed journals, present at professional meetings, and supervise graduate students.
  • Propagation – active propagation is ongoing for rare plant reintroduction, and restoration of Garden nature preserves. The recently created Native Plant Development Center supplies plant material for restoration projects on Garden lands in addition to those in other parts of NC.
  • Seed storage behavior – the Garden performs initial viability tests for species intended for long-term storage and can compare these to seed germination rates of subsequent germination and viability tests.

Garden research includes Citizen Science supported research

NCBG partners with university classes that conduct research in their nature preserves and support “outdoor classroom” events with the local schools. Specific Citizen Science projects include iNaturalist contributions from their nature preserves; ‘Caterpillars Count!’ that measure the seasonal variation (i.e., phenology) and abundance of arthropods like caterpillars, beetles, and spiders found on the foliage of trees and shrubs; ‘Mason Farm Butterfly Project’ to monitor butterflies – primarily to study changes in butterfly flight seasons over time; ‘Project BudBurst – Nativars Research Project’ to answer questions about the ecological value of cultivated varieties of native plants; and ‘ecoEXPLORE’ (Experiences Promoting Learning Outdoors for Research and Education) for children in grades K-8, developed by the North Carolina Arboretum, to combine science exploration with kid-friendly technologies.

Garden collaborates with other research communities to build capacity and provide maximum benefit for plant conservation and biodiversity

The Garden has strong connections with the University of North Carolina at Chapel Hill (UNC-CH) Department of Biology and the Ecology, Environment, and Energy Program where three staff are adjunct faculty. They also cooperate on research projects with the UNC-Chapel Hill Carolina Center for Genome Sciences, Duke University, and North Carolina State University. The Garden also collaborates with SePPCon (Southeast Partners for Plant Conservation) and the botanical institutions associated with the CPC.    

Staff Expertise


Garden Staff makes field-wide contributions to support Plant Conservation and Biodiversity:

The staff at NCBG contribute to numerous conservation efforts within North Carolina and surrounding states. They regularly partner with the NC Plant Conservation Program, The Nature Conservancy, NatureServe, US Fish and Wildlife Service, land trusts throughout the state, NC Natural Heritage Program, SouthEast Regional Network of Expertise and Collections (SERNEC), and CPC.

Garden staff contributes plant conservation expertise in the following areas:

  • Rare plant reintroduction and management
  • Nature preserve design and management
  • Plant systematics and evolution
  • Regional floristics
  • Phylogeography
  • Seed collection, processing, storage, and propagation
  • Ecological restoration
  • Pollination ecology and pollinator conservation
  • Sustainable landscape practices
  • Conservation through propagation
  • Invasive species control and management


Contact Information

Address: 100 Old Mason Farm Rd, Chapel Hill, NC 27517

Phone: (919) 962-0522

No. of species: 2,500

Land area: 700 acres (1.1 sq mi; 2.8 km2)