North America Native Plant

Toano Milkvetch

Botanical name: Astragalus toanus var. scidulus

USDA symbol: ASTOS

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Toano Milkvetch: A Rare Desert Gem Worth Knowing About Meet the Toano milkvetch (Astragalus toanus var. scidulus), a little-known perennial that calls the American Southwest home. While you might not find this plant at your local garden center, it’s worth understanding what makes this native species special – and why ...

Rare plant alert!

Region: Conservation status by state

Status: S4S5T1: Status is uncertain but is somewhere between the following rankings: Subspecies or variety is 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) ⚘ Apparently Secure: Uncommon but not rare, and usually widespread. Possibly cause for longterm concern. Typically more than 100 occurrences in the state or more than 10,000 individuals ⚘ 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. ⚘

Toano Milkvetch: A Rare Desert Gem Worth Knowing About

Meet the Toano milkvetch (Astragalus toanus var. scidulus), a little-known perennial that calls the American Southwest home. While you might not find this plant at your local garden center, it’s worth understanding what makes this native species special – and why it deserves our respect and protection.

Where Does Toano Milkvetch Call Home?

This native beauty has carved out its niche in just two states: Arizona and Utah. As a true native of the lower 48 states, it’s perfectly adapted to the challenging conditions of the southwestern United States. Its limited range makes every population precious.

A Rare Find in the Plant World

Here’s where things get serious: Toano milkvetch carries a Global Conservation Status of S4S5T1. While the technical details of this rating can be complex, what matters most is that this variety is considered quite rare. This isn’t a plant to casually collect or transplant from the wild.

Should You Grow Toano Milkvetch?

The short answer is: probably not, unless you’re involved in serious conservation efforts. Here’s why:

  • Its rarity means wild populations need protection, not disturbance
  • Seeds or plants should only come from legitimate, responsible sources
  • Growing conditions and care requirements are not well-documented
  • It’s adapted to very specific environmental conditions that may be hard to replicate

What We Know About This Desert Dweller

As a perennial member of the legume family, Toano milkvetch shares characteristics with other milkvetches – it likely has the ability to fix nitrogen in the soil and probably sports the typical pea-family flowers. However, specific details about its appearance, size, and growing requirements remain somewhat mysterious, which is common with rare, specialized plants.

The Bigger Picture: Why Rare Plants Matter

Even if you can’t grow Toano milkvetch in your garden, understanding plants like this helps us appreciate the incredible diversity of our native flora. These rare species often play unique ecological roles and represent thousands of years of adaptation to specific environments.

Native Alternatives for Your Garden

If you’re inspired by the idea of growing native milkvetches, consider looking for more common Astragalus species that are appropriate for cultivation and available through reputable native plant nurseries. Your local extension office or native plant society can help you identify suitable alternatives that will thrive in your specific location.

Remember, the best way to support rare plants like Toano milkvetch is to protect their natural habitats and support conservation efforts rather than attempting to grow them ourselves.

Toano 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 toanus M.E. Jones - Toano milkvetch

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