North America Non-native Plant

Astragalus Tephrosioides

Botanical name: Astragalus tephrosioides

USDA symbol: ASTE21

Native status: Not native but doesn't reproduce and persist in the wild

The Mystery Plant: Astragalus tephrosioides and What to Do When Information is Scarce Every now and then, a gardener stumbles upon a plant name that seems to exist in the shadows of botanical literature. Astragalus tephrosioides is one such enigmatic species that leaves even experienced native plant enthusiasts scratching their ...

The Mystery Plant: Astragalus tephrosioides and What to Do When Information is Scarce

Every now and then, a gardener stumbles upon a plant name that seems to exist in the shadows of botanical literature. Astragalus tephrosioides is one such enigmatic species that leaves even experienced native plant enthusiasts scratching their heads. If you’ve come across this name in your plant research, you’re probably wondering what exactly it is and whether you should grow it. Let’s dive into this botanical mystery together.

The Challenge of Obscure Species

Astragalus tephrosioides belongs to the vast Astragalus genus, commonly known as milkvetches or locoweeds. With over 3,000 species worldwide, Astragalus is one of the largest plant genera on Earth. However, this particular species presents a unique challenge: there’s remarkably little documented information available about it in standard botanical references.

This lack of information could indicate several possibilities. The name might refer to an extremely rare species with limited distribution, a taxonomic synonym that has been reclassified, or potentially an outdated or invalid botanical name. Without clear documentation, it’s impossible to determine its native range, growing requirements, or garden suitability.

What We Know About the Astragalus Family

While we can’t speak specifically about Astragalus tephrosioides, we can share some general characteristics of the Astragalus genus that might be helpful:

  • Most species are perennial herbs or small shrubs
  • They typically produce clusters of pea-like flowers
  • Many species are adapted to arid or semi-arid conditions
  • They often have compound leaves with multiple leaflets
  • Some species can fix nitrogen in the soil

The Importance of Accurate Plant Identification

When dealing with obscure or poorly documented plant names, it’s crucial to proceed with caution. Some Astragalus species can be toxic to livestock and wildlife, earning them the common name locoweed. Without proper identification and documentation, it’s impossible to know whether any particular species is safe for your garden or local ecosystem.

Better Alternatives: Well-Documented Native Astragalus Species

Instead of pursuing the mysterious Astragalus tephrosioides, consider these well-documented native Astragalus species that might serve your gardening needs:

  • Purple Prairie Clover (Astragalus canadensis) – A robust perennial perfect for prairie gardens
  • Ground Plum (Astragalus crassicarpus) – Low-growing with interesting inflated seed pods
  • Woolly Milkvetch (Astragalus mollissimus) – Drought-tolerant with silvery foliage

What Should You Do?

If you’re specifically interested in Astragalus tephrosioides, here’s our recommendation:

  • Consult with local botanical experts or native plant societies
  • Check with university herbaria for verified specimens
  • Consider whether you might have encountered a misidentification
  • Explore well-documented native alternatives instead

The Bottom Line

While the plant world is full of fascinating species waiting to be discovered or rediscovered, gardening with mystery plants can be risky. Without clear information about a plant’s native status, growing requirements, and ecological impact, it’s better to choose well-documented alternatives that will provide known benefits to your garden and local wildlife.

Remember, successful native gardening relies on accurate plant identification and understanding each species’ role in the ecosystem. When in doubt, stick with the tried-and-true native plants that have plenty of growing information available. Your garden—and the local wildlife—will thank you for it.

Astragalus Tephrosioides

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

Astragalus L. - milkvetch

Species

Astragalus tephrosioides Boiss.

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