North America Native Plant

Rayless Tansyaster

Botanical name: Machaeranthera grindelioides var. depressa

USDA symbol: MAGRD

Life cycle: perennial

Habit: subshrub

Native status: Native to the lower 48 states  

Synonyms: Haplopappus nuttallii Torr. & A. Gray var. depressus Maguire (HANUD)   

Rayless Tansyaster: A Rare Southwest Native Worth Knowing If you’re passionate about native plants from the American Southwest, you might have stumbled across the intriguing rayless tansyaster (Machaeranthera grindelioides var. depressa). This lesser-known native perennial deserves a closer look, though it comes with some important considerations for the home gardener. ...

Rare plant alert!

Region: Conservation status by state

Status: S5T3T4: Status is uncertain but is somewhere between the following rankings: Subspecies or variety is vulnerable: Either very rare and local throughout its range, found only in a restricted range (even if abundant at some locations), or factors are making it vulnerable to extinction. Typically 21 to 100 occurrences or between 3,000 and 10,000 individuals. ⚘ Subspecies or varieties is apparently secure: Uncommon but not rare, and usually widespread. Possibly cause for longterm concern. Typically more than 100 occurrences in the region 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. ⚘

Rayless Tansyaster: A Rare Southwest Native Worth Knowing

If you’re passionate about native plants from the American Southwest, you might have stumbled across the intriguing rayless tansyaster (Machaeranthera grindelioides var. depressa). This lesser-known native perennial deserves a closer look, though it comes with some important considerations for the home gardener.

What Is Rayless Tansyaster?

Rayless tansyaster is a perennial forb—essentially a non-woody flowering plant that comes back year after year. As the name suggests, this plant belongs to the aster family but has a unique characteristic that sets it apart from its showier cousins. It’s a true native of the lower 48 states, making it an authentic choice for native plant enthusiasts.

You might also encounter this plant listed under its scientific synonym, Haplopappus nuttallii var. depressus, as plant names sometimes change as botanists learn more about plant relationships.

Where Does It Call Home?

This hardy native has carved out its niche across three southwestern states: Arizona, Nevada, and Utah. It’s perfectly adapted to the unique growing conditions of this region, having evolved alongside local wildlife and weather patterns over thousands of years.

A Word About Rarity

Here’s something important to know: rayless tansyaster has a conservation status that suggests it may be uncommon in parts of its range. If you’re considering adding this plant to your garden, it’s crucial to source it responsibly. Never collect plants from the wild, and always purchase from reputable native plant nurseries that grow their stock rather than wild-harvest it.

Should You Grow Rayless Tansyaster?

The decision to grow this plant comes with both excitement and responsibility. On the plus side:

  • It’s a true native that supports local ecosystems
  • As a perennial, it provides long-term garden value
  • It’s adapted to southwestern growing conditions
  • You’ll be helping preserve a less common native species

However, there are some challenges to consider:

  • Limited availability due to its rarity
  • Specific growing requirements that aren’t well-documented
  • May not provide the showy flowers some gardeners expect

Growing Conditions and Care

Like many southwestern natives, rayless tansyaster likely prefers well-draining soils and can handle drought conditions once established. However, specific growing requirements for this particular variety aren’t well-documented in readily available sources. If you’re lucky enough to find this plant at a specialty native nursery, be sure to ask about their specific care recommendations.

Given its native range across Arizona, Nevada, and Utah, it’s probably best suited for xeriscaping and native plant gardens in similar climates.

The Bottom Line

Rayless tansyaster represents the kind of plant that makes native gardening both exciting and meaningful—it’s a true local native with an important ecological role, even if it’s not the showiest plant in the garden. If you can find it through responsible sources and have the right growing conditions, it could be a wonderful addition to a native plant collection.

However, given its apparent rarity and limited availability, you might also consider other southwestern native asters that are more readily available and better documented. Your local native plant society or extension office can help you identify similar native alternatives that might be easier to grow and source responsibly.

Remember, the best native plant for your garden is one you can grow successfully while supporting conservation efforts—sometimes that means choosing the less rare cousin over the botanical unicorn.

Rayless Tansyaster

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Asteridae

Order

Asterales

Family

Asteraceae Bercht. & J. Presl - Aster family

Genus

Machaeranthera Nees - tansyaster

Species

Machaeranthera grindelioides (Nutt.) Shinners - rayless tansyaster

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