Mid-Elevation Rare Plant Facilities

The Hawaii Rare Plant Restoration Group recognized the need for mid-elevation nurseries and protected outplanting sites which are necessary adjuncts to propagation and ex situ conservation at existing lower elevation botanical gardens.


The Hawaiian Islands are the most isolated high islands in the world, located over 2,000 miles from the nearest continental land mass. This isolation and a wide diversity of habitats have made the Hawaiian flora one of the most unique in the world. Nearly 90% of the plant species native to the Hawaiian Islands are found nowhere else in the world. Pressures from human population growth and introduced plants and animals have put these unique species at great risk. The narrow geographic range of many native species makes them more susceptible to decline in habitat and the immediate impact of threats such as introduced ungulates, plants, and herbivorous insects. Already, approximately 100 of known Hawaiian plant species are considered extinct, and roughly another 225 species have fewer than 50 individuals remaining each.

The conservation challenge in Hawaii is for the numerous State and Federal agencies and private organizations to work together to protect remaining native ecosystems and their components. Without the protection of the remaining ecosystems through the control of alien species, conservation of individual species will not be possible. However, in many cases numerous factors have driven some species to such low levels that habitat protection alone will not recover the species. In these cases, it is imperative that emergency management actions be undertaken for plant species at particularly high risk of extinction. These emergency actions take two forms; in situ (on site) control of the immediate threats, such as spot fencing to control ungulates, rat control, and invertebrate control, as well as ex situ (off site) propagation to bank against extinction and allow reintroduction into protected habitat. The reintroduction of plant species is a critical step in the restoration of Hawaiian ecosystems; the interactions between plants and birds and/or invertebrates is what makes the ecosystem function. The Rare Plant Facilities play an essential role in the overall strategy for plant and ecosystem conservation on the Hawaiian Islands. Their strategy requires working closely with other conservation organizations, particularly land managers, to ensure that plant material for reintroduction is available concurrent with habitat that is suitably protected to allow the survival of the species.

The botanical gardens in Hawaii, as well as the State of Hawaii’s baseyards, are all located at low elevations, while approximately 75% of Hawaii’s endangered flora occur between 1,000 and 5,500 feet. The need for mid-elevation facilities on Kauai, Oahu, Maui, and Hawaii is obvious. As more fencing projects on state and private lands are completed, there will be a growing need for a source of plant material to be used in rare plant restoration projects. Additionally, private landowners or other cooperators may initiate management plans for the conservation of rare species. The Rare Plant Facilities provide a source of genetically appropriate plants for recovery and conservation on each island. For this reason, the continued operation of a mid-elevation plant facility is most timely.

Mission and Objectives

The mission of the Rare Plant Facilities (RPF) is to assist in ex situ aspects of the recovery of endangered and threatened plants and other declining plant species as part of a larger strategy to reintroduce species back into suitable protected and managed habitat. While it is preferable to return the species as quickly as possible to suitable habitat, the degradation and continual decline of native ecosystems in Hawaii will require that some of the more rare species be held for longer periods in a cultivated setting. For those species, outplanting on the RPF site or in small exclosures of more suitable habitat will be used as a short- to mid-term method of maintaining the species' genetic integrity inter-situ while waiting for suitable large-scale habitat for reintroduction efforts.

The main objectives of the RPFs are listed below. Priorities will shift as propagative material is made available and as plants are reintroduced, but should follow the order given here:

1. Propagation and storage of Plant Extinction Prevention mid-elevation species (less than 50 individuals in the wild) that cannot be stored as seed or in tissue culture, with priority to island-specific species.

2. Propagation testing for Plant Extinction Prevention mid-elevation species for which propagation techniques to raise plants to reproduction stage are not yet known.

3. Propagation of reintroduction material from Plant Extinction Prevention mid-elevation species from the appropriate island as needed for land managers with protected habitats when accompanied by a well developed reintroduction plan.

4. Gene pool bank of other than Plant Extinction Prevention mid-elevation species from the appropriate source that cannot be stored as seed or in tissue culture.

5. Propagation of rare plant material (non-Plant Extinction Prevention species) from the appropriate island as needed for land managers with protected habitats when accompanied by a well developed reintroduction plan.

6. Production of more common native species for restoration efforts, provided time and resources are available and the operation is self-supporting and does not detract from the first five goals.

7. Education, provided it is self-supporting and does not detract from the first five goals.