North America Native Plant

Trelease’s Milkvetch

Botanical name: Astragalus racemosus var. treleasei

USDA symbol: ASRAT

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Trelease’s Milkvetch: A Rare Mountain Treasure Worth Protecting Meet Trelease’s milkvetch (Astragalus racemosus var. treleasei), a fascinating native perennial that’s quietly holding down the fort in some of the most rugged landscapes of the American West. This little-known member of the legume family might not be the flashiest plant in ...

Rare plant alert!

Region: Conservation status by state

Status: S5T2: Status is uncertain but is somewhere between the following rankings: 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. ⚘

Trelease’s Milkvetch: A Rare Mountain Treasure Worth Protecting

Meet Trelease’s milkvetch (Astragalus racemosus var. treleasei), a fascinating native perennial that’s quietly holding down the fort in some of the most rugged landscapes of the American West. This little-known member of the legume family might not be the flashiest plant in your garden center, but it’s got a story worth telling – and a conservation status that makes it extra special.

Where Does Trelease’s Milkvetch Call Home?

This hardy perennial is a true child of the Mountain West, making its home exclusively in Utah and Wyoming. It’s perfectly adapted to the challenging conditions of high-elevation landscapes, where many other plants simply can’t cut it. As a native species to the lower 48 states, it’s been quietly supporting local ecosystems for countless generations.

Why the Conservation Concern?

Here’s where things get serious: Trelease’s milkvetch carries a Global Conservation Status of S5T2, which means while the overall species group is stable, this particular variety is considered imperiled. This rare status makes it a plant worth protecting and appreciating, but it also means we need to be extra thoughtful about how we source and grow it.

Should You Grow Trelease’s Milkvetch?

If you’re gardening in Utah or Wyoming and want to support native biodiversity, this milkvetch could be a wonderful addition to your landscape – but only if you can source it responsibly. Here’s what makes it appealing:

  • It’s a true native that supports local ecosystems
  • As a legume, it likely provides benefits to native pollinators
  • It’s adapted to challenging mountain conditions
  • Perennial growth means it’s a long-term investment in your landscape

Important note: Due to its imperiled status, only plant Trelease’s milkvetch if you can obtain it from reputable native plant nurseries that use responsibly sourced, nursery-propagated material. Never collect from wild populations.

Growing Conditions and Care

While specific growing information for this variety is limited, we can make educated guesses based on its natural habitat and family characteristics:

  • Likely prefers full sun to partial shade
  • Probably needs well-drained soils (most Astragalus species hate wet feet)
  • Should be hardy in the mountain regions where it naturally occurs
  • May benefit from minimal supplemental water once established

The Bottom Line

Trelease’s milkvetch represents something special in the native plant world – a rare variety that’s hanging on in some pretty tough places. If you’re passionate about native plant conservation and happen to garden in its native range, seeking out responsibly sourced plants could be a meaningful way to support biodiversity. Just remember that with rarity comes responsibility: always source ethically and consider this plant a privilege to grow rather than just another garden addition.

Sometimes the most rewarding plants aren’t the showiest ones – they’re the ones that connect us to the wild landscapes we call home and remind us that every species has a story worth preserving.

Trelease’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 racemosus Pursh - cream milkvetch

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