North America Native Plant

Torrey’s Milkvetch

Botanical name: Astragalus calycosus var. monophyllidius

USDA symbol: ASCAM2

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Torrey’s Milkvetch: A Rare Desert Gem Worth Protecting If you’re drawn to rare native plants with a story to tell, Torrey’s milkvetch (Astragalus calycosus var. monophyllidius) might just capture your imagination. This perennial beauty represents one of nature’s more exclusive offerings, found only in the desert landscapes of Nevada and ...

Rare plant alert!

Region: Conservation status by state

Status: S5T2Q: Status is uncertain but is somewhere between the following rankings: Uncertain taxonomy: ⚘ Subspecies or variety is imperiled: Extremely rare due to factor(s) making it especially vulnerable to extinction. Typically 6 to 20 occurrences or few remaining individuals (1,000 to 3,000) ⚘ Secure: At very low or no risk of extinction in the jurisdiction due to a very extensive range, abundant populations or occurrences, with little to no concern from declines or threats. ⚘

Torrey’s Milkvetch: A Rare Desert Gem Worth Protecting

If you’re drawn to rare native plants with a story to tell, Torrey’s milkvetch (Astragalus calycosus var. monophyllidius) might just capture your imagination. This perennial beauty represents one of nature’s more exclusive offerings, found only in the desert landscapes of Nevada and Utah.

Where You’ll Find This Desert Native

Torrey’s milkvetch calls the American Southwest home, specifically thriving in the unique ecosystems of Nevada and Utah. As a native plant species of the lower 48 states, it has spent centuries adapting to the challenging conditions of these desert regions, making it perfectly suited to its natural habitat.

A Plant with Conservation Concerns

Here’s where things get interesting – and a bit concerning. Torrey’s milkvetch carries a Global Conservation Status of S5T2Q, which indicates this variety faces some level of conservation concern. This rare status means that if you’re lucky enough to encounter this plant in cultivation, you’ll want to ensure any specimens come from responsibly sourced, legally obtained material.

Why Consider Growing Torrey’s Milkvetch?

As a perennial member of the legume family, Torrey’s milkvetch offers several compelling reasons for the dedicated native plant enthusiast:

  • Supports native plant conservation efforts
  • Perfectly adapted to challenging desert conditions
  • Part of the diverse milkvetch family known for ecological benefits
  • Connects your garden to the unique flora of the American Southwest

Growing Conditions and Care

Like most desert natives, Torrey’s milkvetch likely prefers well-draining soils and can handle the extreme temperature fluctuations common in Nevada and Utah. While specific growing requirements for this variety aren’t widely documented, most milkvetches thrive in:

  • Full sun exposure
  • Sandy or rocky, well-draining soils
  • Minimal supplemental watering once established
  • Hot, dry summers and cold winters

A Word of Caution for Potential Growers

Given its conservation status and limited natural range, Torrey’s milkvetch isn’t your typical garden center find. If you’re interested in growing this species, it’s crucial to:

  • Source plants only from reputable native plant nurseries
  • Ensure all material is legally and ethically obtained
  • Consider participating in conservation seed collection programs
  • Never collect plants from wild populations

The Bigger Picture

While Torrey’s milkvetch might not be the easiest native plant to find or grow, it represents something important: the incredible diversity of our native flora and the need to protect these unique species. Whether you’re able to grow it in your garden or simply appreciate it in its natural habitat, this rare milkvetch reminds us why native plant conservation matters.

For most gardeners interested in supporting native ecosystems, consider exploring other native milkvetch species or drought-tolerant natives from your specific region. Every native plant we grow, rare or common, contributes to biodiversity and ecological health in our landscapes.

Torrey’s Milkvetch

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 calycosus Torr. ex S. Watson - Torrey's milkvetch

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