North America Native Plant

Subterranean Indian Breadroot

Botanical name: Pediomelum hypogaeum var. subulatum

USDA symbol: PEHYS2

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Pediomelum subulatum (Bush) Rydb. (PESU11)  âš˜  Psoralea subulata Bush (PSSU)  âš˜  Psoralea subulata Bush var. minor Shinners (PSSUM)   

Subterranean Indian Breadroot: A Rare Native Treasure Worth Protecting Meet the subterranean Indian breadroot (Pediomelum hypogaeum var. subulatum), a fascinating but exceptionally rare native plant that’s as elusive as its name suggests. This little-known perennial forb represents one of our region’s botanical treasures – and one that desperately needs our ...

Rare plant alert!

Region: Arkansas

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) ⚘

Subterranean Indian Breadroot: A Rare Native Treasure Worth Protecting

Meet the subterranean Indian breadroot (Pediomelum hypogaeum var. subulatum), a fascinating but exceptionally rare native plant that’s as elusive as its name suggests. This little-known perennial forb represents one of our region’s botanical treasures – and one that desperately needs our protection.

A Plant with Many Names

Botanically known as Pediomelum hypogaeum var. subulatum, this plant has traveled through several scientific name changes over the years. You might also find it listed under its former names like Pediomelum subulatum or Psoralea subulata in older botanical references. The subterranean part of its common name hints at its unique underground characteristics that make it so special.

Where to Find This Rare Native

This native American plant calls the south-central United States home, with populations documented in Arkansas, Louisiana, Oklahoma, and Texas. However, don’t expect to stumble across it on your next nature walk – this species is critically rare, especially in Arkansas where it holds an S1 rarity status, meaning it’s critically imperiled.

What Makes It Special

As a perennial forb, subterranean Indian breadroot lacks the woody stems you’d find on shrubs or trees. Instead, it’s an herbaceous plant that returns year after year from underground parts. Like other members of the legume family, it likely produces small flowers that can provide nectar for native bees and other pollinators, though its blooms are typically inconspicuous.

Should You Grow Subterranean Indian Breadroot?

Here’s where we need to have an honest conversation. While this native plant deserves our appreciation and protection, it’s not your typical garden center find – and for good reason.

The Rarity Reality Check

With its critically imperiled status, particularly in Arkansas, this plant faces serious conservation challenges. If you’re passionate about growing this species, here are the essential guidelines:

  • Only obtain plants or seeds from reputable native plant nurseries with documented ethical sourcing
  • Never collect from wild populations – this could push local populations closer to extinction
  • Consider supporting conservation organizations working to protect this species instead
  • If you do grow it, participate in seed collection programs to help conservation efforts

Growing Conditions and Care

Based on its native range across the south-central United States, subterranean Indian breadroot likely thrives in USDA hardiness zones 7-9. Like many prairie natives, it probably prefers:

  • Full sun exposure
  • Well-drained soils
  • Minimal supplemental watering once established
  • Native soil conditions rather than heavily amended garden beds

However, specific cultivation requirements remain largely unstudied due to the plant’s rarity, making it challenging even for experienced native plant gardeners.

Garden Alternatives

If you’re drawn to rare native legumes but want more readily available options, consider these related species that offer similar ecological benefits:

  • Other Pediomelum species that are more common in your region
  • Native wild indigos (Amorpha species)
  • Local prairie clovers (Dalea species)

The Bottom Line

Subterranean Indian breadroot represents the kind of botanical treasure that makes native plant conservation so important. While it may not be the showiest addition to your garden, its rarity makes it precious beyond measure. If you’re committed to growing this species, do so responsibly and consider it part of your contribution to conservation efforts.

Sometimes the most meaningful gardening choices aren’t about what looks best in our landscapes, but about what needs our protection most. This little-known native certainly qualifies as the latter.

Subterranean Indian Breadroot

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

Pediomelum Rydb. - Indian breadroot

Species

Pediomelum hypogaeum (Nutt. ex Torr. & A. Gray) Rydb. - subterranean Indian breadroot

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