North America Native Plant

Kipuka Piaula

Botanical name: Melicope zahlbruckneri

USDA symbol: MEZA

Life cycle: perennial

Habit: tree

Native status: Native to Hawaii  

Synonyms: Pelea zahlbruckneri Rock (PEZA)   

Kipuka Piaula: A Rare Hawaiian Treasure Worth Protecting If you’re passionate about native Hawaiian plants and conservation, you may have heard whispers about kipuka piaula (Melicope zahlbruckneri), one of Hawaii’s most endangered native trees. This remarkable species represents both the incredible biodiversity of the Hawaiian Islands and the urgent need ...

Rare plant alert!

Region: United States

Status: S1: Status is uncertain but is somewhere between the following rankings: Critically Imperiled: Extremely rare due to factor(s) making it especially vulnerable to extinction. Typically 5 or fewer occurrences or very few remaining individuals (<1,000) ⚘ Endangered: In danger of extinction throughout all or a significant portion of its range. ⚘

Region: United States

Kipuka Piaula: A Rare Hawaiian Treasure Worth Protecting

If you’re passionate about native Hawaiian plants and conservation, you may have heard whispers about kipuka piaula (Melicope zahlbruckneri), one of Hawaii’s most endangered native trees. This remarkable species represents both the incredible biodiversity of the Hawaiian Islands and the urgent need for plant conservation efforts.

What Makes Kipuka Piaula Special?

Kipuka piaula belongs to the citrus family and is endemic to Hawaii, meaning it exists nowhere else on Earth. This perennial tree typically grows as a single-trunked specimen reaching heights of 13-16 feet or more, making it a substantial presence in its native habitat. Also known by its scientific synonym Pelea zahlbruckneri, this tree is part of Hawaii’s unique evolutionary story.

Where Does Kipuka Piaula Grow?

This rare native is found exclusively in Hawaii, with its limited population concentrated on the Big Island. The tree’s natural habitat represents just a tiny fraction of what it once was, making every remaining specimen precious.

A Critical Conservation Concern

Here’s where things get serious: kipuka piaula has a Global Conservation Status of S1, meaning it’s critically imperiled. With typically five or fewer known occurrences and very few remaining individuals (fewer than 1,000), this species is classified as Endangered in the United States. This isn’t just rare—it’s on the brink.

If you’re considering adding this tree to your landscape, please understand the gravity of its situation. Any planting should only be done with:

  • Plants from verified, responsibly managed sources
  • Proper permits and documentation
  • Collaboration with Hawaiian native plant societies or botanical institutions
  • A long-term commitment to conservation goals

Growing Kipuka Piaula: For the Dedicated Conservationist

If you have legitimate access to kipuka piaula through conservation programs, here’s what this special tree needs:

Climate Requirements

Suitable for USDA hardiness zones 10-12, kipuka piaula thrives in Hawaii’s tropical climate. It’s adapted to the specific conditions of Hawaiian forests and may struggle in significantly different environments.

Ideal Growing Conditions

While specific growing requirements for this rare species aren’t well-documented, related Melicope species typically prefer:

  • Well-draining soil
  • Partial shade to full sun exposure
  • Protection from strong winds
  • Consistent moisture without waterlogging

Landscape Role and Design

In the right hands, kipuka piaula serves as more than just a garden plant—it’s a living piece of Hawaiian heritage. This tree works beautifully in:

  • Native Hawaiian restoration projects
  • Educational botanical gardens
  • Conservation-focused landscapes
  • Cultural preservation sites

Its moderate size makes it suitable for residential landscapes, but remember, growing this tree is a responsibility, not just a hobby.

Supporting Hawaiian Native Plants

If kipuka piaula isn’t available through legitimate conservation channels, consider supporting Hawaiian native plant conservation in other ways:

  • Plant other native Hawaiian species that are more readily available
  • Support local native plant societies and botanical gardens
  • Volunteer for habitat restoration projects
  • Educate others about Hawaiian plant conservation

The Bottom Line

Kipuka piaula represents both the wonder and fragility of Hawaiian native ecosystems. While it’s not a plant for casual gardening, it’s a species that deserves our respect, protection, and careful stewardship. If you’re fortunate enough to grow this rare tree, you’re not just adding to your garden—you’re participating in one of the most important conservation efforts in the Pacific.

Remember, every endangered plant species we lose is gone forever. Let’s make sure future generations can still marvel at the beauty of kipuka piaula in Hawaii’s native forests.

Kipuka Piaula

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Rosidae

Order

Sapindales

Family

Rutaceae Juss. - Rue family

Genus

Melicope (J.R. Forst. & G. Forst.) T.G. Hartley & B.C. Stone - melicope

Species

Melicope zahlbruckneri (Rock) T.G. Hartley & B.C. Stone - kipuka piaula

Plant data source: USDA, NRCS 2025. The PLANTS Database. https://plants.usda.gov,. 2/25/2025. National Plant Data Team, Greensboro, NC USA