North America Native Plant

Largeleaf Leather-root

Botanical name: Orbexilum macrophyllum

USDA symbol: ORMA2

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Psoralea macrophylla Rowlee (PSMA3)   

Largeleaf Leather-Root: A Lost Treasure of North Carolina’s Native Flora Sometimes the most compelling stories in native gardening are about the plants we can no longer grow. Meet largeleaf leather-root (Orbexilum macrophyllum), a native North Carolina wildflower that serves as a sobering reminder of what we’ve lost and why conservation ...

Rare plant alert!

Region: Conservation status by state

Status: SX: Status is uncertain but is somewhere between the following rankings: Presumed Extinct: Believed to be extinct. Not located despite intensive searches and virtually no likelihood that it will be rediscovered ⚘

Largeleaf Leather-Root: A Lost Treasure of North Carolina’s Native Flora

Sometimes the most compelling stories in native gardening are about the plants we can no longer grow. Meet largeleaf leather-root (Orbexilum macrophyllum), a native North Carolina wildflower that serves as a sobering reminder of what we’ve lost and why conservation matters in our gardens.

What Was Largeleaf Leather-Root?

Largeleaf leather-root was a perennial forb—essentially a non-woody flowering plant—that once called North Carolina home. As its name suggests, this member of the legume family was distinguished by its notably large leaflets, setting it apart from its relatives in the Orbexilum genus.

This plant was also known by its former scientific name, Psoralea macrophylla, before taxonomists reclassified it into the Orbexilum genus. Like other members of the pea family, it likely produced small, purple flowers that would have been a welcome sight for native pollinators.

Where Did It Grow?

Largeleaf leather-root was endemic to North Carolina, meaning it grew nowhere else on Earth. This limited range made it particularly vulnerable to habitat loss and environmental changes.

The Heartbreaking Reality: Presumed Extinct

Here’s where this story takes a tragic turn. Largeleaf leather-root has a Global Conservation Status of SX, which means it’s Presumed Extirpated. In plain English, scientists believe this plant is extinct. Despite intensive searches, it hasn’t been found in decades, and experts hold little hope for its rediscovery.

This means you cannot and should not attempt to plant largeleaf leather-root in your garden—it’s simply no longer available.

What This Means for Native Gardeners

While we can’t bring back largeleaf leather-root, its story offers important lessons for today’s native gardeners:

  • Native plants with limited ranges are especially precious and vulnerable
  • Habitat preservation is crucial for plant conservation
  • Every native garden helps support biodiversity and can serve as a refuge for other at-risk species

Honoring Its Memory Through Native Alternatives

Instead of largeleaf leather-root, North Carolina gardeners can choose from other native Orbexilum species and related legumes that provide similar ecological benefits:

  • Sampson’s snakeroot (Orbexilum pedunculatum) – another native leather-root species
  • Wild lupine (Lupinus perennis) – supports native pollinators and the endangered Karner blue butterfly
  • Partridge pea (Chamaecrista fasciculata) – an annual legume that fixes nitrogen in soil

A Call to Action

The loss of largeleaf leather-root reminds us that native gardening isn’t just about pretty flowers—it’s about conservation. Every time you choose native plants over non-native alternatives, you’re creating habitat, supporting pollinators, and helping prevent other species from following the same path to extinction.

While we can’t turn back time for largeleaf leather-root, we can honor its memory by making our gardens into sanctuaries for the native plants that remain. After all, today’s common native might be tomorrow’s rarity if we don’t act as thoughtful stewards of our natural heritage.

Largeleaf Leather-root

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

Fabales

Family

Fabaceae Lindl. - Pea family

Genus

Orbexilum Raf. - leather-root

Species

Orbexilum macrophyllum (Rowlee) Rydb. - largeleaf leather-root

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