North America Native Plant

Woolly Locoweed

Botanical name: Astragalus mollissimus var. matthewsii

USDA symbol: ASMOM2

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Astragalus bigelovii A. Gray var. matthewsii (S. Watson) M.E. Jones (ASBIM4)  âš˜  Astragalus matthewsii S. Watson (ASMA13)   

Woolly Locoweed: A Rare New Mexico Native Worth Knowing About If you’re passionate about native plants and happen to live in New Mexico, you might have stumbled across the name Astragalus mollissimus var. matthewsii, commonly known as woolly locoweed. This perennial plant is a fascinating example of regional plant diversity, ...

Woolly Locoweed: A Rare New Mexico Native Worth Knowing About

If you’re passionate about native plants and happen to live in New Mexico, you might have stumbled across the name Astragalus mollissimus var. matthewsii, commonly known as woolly locoweed. This perennial plant is a fascinating example of regional plant diversity, but before you rush to add it to your garden wish list, there are some important things to consider.

What Makes This Plant Special?

Woolly locoweed is a true New Mexico native, found nowhere else in the world. As a member of the legume family (think beans and peas), it’s part of a group of plants known for their ability to fix nitrogen in the soil – a pretty neat trick that can actually benefit other plants around it.

This perennial has earned its woolly nickname honestly, thanks to its fuzzy, soft-textured foliage that gives it a distinctive appearance in the landscape. Like other members of the Astragalus genus, it’s adapted to the unique growing conditions of the American Southwest.

Where You’ll Find It Growing Wild

This variety of woolly locoweed calls New Mexico home, making it a truly local treasure. It’s specifically adapted to the state’s unique climate and soil conditions, which means it’s perfectly suited to thrive in its native range.

The Garden Reality Check

Here’s where things get a bit complicated. While woolly locoweed might sound like an interesting native plant to try, there are several reasons why most gardeners should probably admire it from afar:

  • Limited availability: You’re unlikely to find this plant at your local nursery, and for good reason
  • Specialized needs: As a highly specialized native, it likely has very specific growing requirements that are difficult to replicate in typical garden settings
  • Potential concerns: Members of this plant group can contain compounds that may be problematic if consumed by livestock or pets
  • Conservation considerations: With limited distribution, it’s best left in its natural habitat

Better Native Alternatives for Your Garden

If you’re drawn to native New Mexico plants with similar characteristics, consider these more garden-friendly options:

  • Purple Prairie Clover (Dalea purpurea): Another nitrogen-fixing native with attractive flowers
  • Desert Willow (Chilopsis linearis): A beautiful flowering native shrub
  • Four O’Clock (Mirabilis multiflora): A hardy perennial native with showy flowers
  • Native bunch grasses: Perfect for creating natural-looking landscapes

Appreciating Woolly Locoweed in the Wild

The best way to enjoy this unique plant is to appreciate it where it belongs – in its natural New Mexico habitat. If you’re lucky enough to spot it during a nature walk or hike, take a moment to observe its fuzzy foliage and consider the incredible adaptation that allows it to thrive in such specific conditions.

Remember, every native plant plays a role in its ecosystem, even if we don’t fully understand all the connections. By leaving rare and specialized plants like woolly locoweed in their natural homes and choosing more widely available natives for our gardens, we can support both biodiversity and successful gardening.

The Bottom Line

While Astragalus mollissimus var. matthewsii is certainly an interesting piece of New Mexico’s botanical puzzle, it’s not practical or advisable for most home gardens. Instead, channel your enthusiasm for native plants into species that are better suited to cultivation and more readily available. Your local native plant society or extension office can help you discover the many wonderful native plants that will thrive in your New Mexico garden while supporting local wildlife and conserving water.

Woolly Locoweed

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 mollissimus Torr. - woolly locoweed

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