Tropical Plant Database - Plant Details

Pittosporum napaliense is a small tree that grows from 5-11 m tall. The young parts of the plant are covered with pale brown hairs which are often lost over time and the branches become smooth. Like all Hawaiian Pittosporum species the leaves are alternately arranged on the branches however this is sometimes difficult to see as the leaves are often densely clustered at the ends of the branches. The leaves are somewhat leathery, broadly ovate to oblong-ovate in shape, 21-31 cm long and 7-9.5 cm wide. The leaf margins are entire and often rolled towards the underside of the leaf. The upper surfaces of older leaves are glossy green, with slightly sunken leaf veins while the lower surfaces of older and young leaves are covered with white hairs and the leaf veins are conspicuously raised.
The flowers of Pittosporum napaliense are found in branched or unbranched inflorescences (clusters of flowers) containing between 8-20 flowers. The inflorescence is borne on a short stalk that is 0.5-3 cm long. A single tree will produce either staminate (pollen producing) or pistillate (ovule producing) flowers. Each flower has a small leaf-like bract at the base of the flower stalk which is 9-17 mm long. The calyx (green structures outside of the petals) forms a tube with five distinct lobes that have short brown hairs on both the inner and outer surface. The flower petals are cream to white in color and form a tube that is 14-18 mm long before dividing to form five lobes. The flowers are fragrant at night. The fruit of Pittosporum napaliense is an oval capsule which is oblong to ovoid in shape. The short, narrow stalk seen at the top of the capsule is the style of the flower which is retained in the fruit. The outer surface of the capsule is wrinkled and covered with very short white-pale brown hairs which may be lost over time. The capsules open at maturity to reveal the orange or red inner surface. The capsules are 1-2 cm in length and each capsule contains up to 20 seeds that are black to reddish black, compressed and about 5 to 7 mm long.

(Wagner, W. L., Herbst, D. R., and S. H. Sohmer. 1999. Manual of the Flowering Plants of Hawai`i. Revised Edition. Volume 2. Bishop Museum Special Publication 97. University of Hawai`i Press, Bishop Museum Press, Honolulu, Hawai`i.)

These plants have been reported to be poisonous however details on the specific parts with toxic properties are not provided in the references identified.
(Merlin, M. 1999. Hawaiian Forest Plants. Pacific Guide Books, Honolulu, HI.)

Ho'awa is endemic to the Na Pali Coast on Kaua`i and is currently found in only six populations, containing several hundred individuals on the eastern portion of the Na Pali coast from Limahuli to Hanakoa Valleys. It is found in disturbed Hala (Pandanus tectorius: Pandanaceae) forests and mesic valleys, at elevations ranging from 150-500 m.

(US Fish and Wildlife Service, 2005. Endangered and Threatened Wildlife and
Plants; Review of Plant and Animal Taxa That Are Candidates or Proposed for
Listing as Endangered or Threatened; Annual Notice of Findings on Recycled
Petitions; Annual Description of Progress on Listing Actions; Proposed Rule. CFR (70) 90: 24870-24934).

The native Hawaiian Pittosporum species share the names Ha'awa or Ho'awa. The Latin name of the genus derives from the Greek words "pittos", meaning pitch and "sporos" meaning seeds, in reference to the black seeds covered with a film of viscous resin. The species name napaliense refers to the geographic distribution of this species which is restricted to the Na Pali Coast of Kaua`i.
(Wagner, W. L., Herbst, D. R., and S. H. Sohmer. 1999. Manual of the Flowering Plants of Hawai`i. Revised Edition. Volume 2. Bishop Museum Special Publication 97. University of Hawai`i Press, Bishop Museum Press, Honolulu, Hawai`i.)

Pittosporum napaliense is currently listed as a candidate species on the United States Federal Register for possible addition to the List of Endangered and Threatened Wildlife and Plants. In 2005 the listing priority of this species was increased from level 5 to level 2 due to the ongoing threats to this species. Ho'awa is currently known from about six populations, containing several hundred individuals on the eastern portion of the Na Pali coast. Identified threats to the persistence of these populations include habitat disturbance by feral pigs and subsequent invasion of this habitat by nonnative plants.
(US Fish and Wildlife Service, 1999. Endangered and Threatened Wildlife and
Plants; Review of Plant and Animal Taxa That Are Candidates or Proposed for
Listing as Endangered or Threatened; Annual Notice of Findings on Recycled
Petitions; Annual Description of Progress on Listing Actions; Proposed Rule. CFR (64) 205: 57532-57547).
(US Fish and Wildlife Service, 2005. Endangered and Threatened Wildlife and
Plants; Review of Plant and Animal Taxa That Are Candidates or Proposed for
Listing as Endangered or Threatened; Annual Notice of Findings on Recycled
Petitions; Annual Description of Progress on Listing Actions; Proposed Rule. CFR (70) 90: 24870-24934).

We currently have 27 herbarium specimens for Pittosporum napaliense in our collection. Click on any specimen below to view the herbarium sheet data.

• 017466 - collected by Dan Moriarty in 1976
• 017468 - collected by Tim Flynn in 1983
• 017467 - collected by David H. Lorence in 1987
• 013634 - collected by Steve Perlman in 1989
• 013633 - collected by Steve Perlman in 1989
• 021586 - collected by Steve Perlman in 1996
• S047714 - collected by Steve Perlman in 1996
• 028249 - collected by Steve Perlman in 1999
• 030476 - collected by David H. Lorence in 2004
• 045800 - collected by Steve Perlman in 2004
• 052010 - collected by K. R. Wood in 2008
• 051915 - collected by Steve Perlman in 2009
• S062038 - collected by Steve Perlman in 2009
• 071520 - collected by Natalia Tangalin in 2012
• 072980 - collected by Natalia Tangalin in 2012
• 068578 - collected by Steve Perlman in 2012
• 069403 - collected by Merlin Edmonds in 2015
• Unassigned - collected by Natalia Tangalin in 2015
• 072204 - collected by Merlin Edmonds in 2015
• 074892 - collected by Dustin Wolkis in 2016
• 080019 - collected by K. R. Wood in 2017
• Unassigned - collected by Seana Walsh in 2017
• Unassigned - collected by Seana Walsh in 2017
• 080278 - collected by K. R. Wood in 2017
• 092069 - collected by Uma Nagendra in 2019
• 087945 - collected by David H. Lorence in 2020
• Unassigned - collected by Uma Nagendra in 2022