North America Native Plant

Washoe Combleaf

Botanical name: Polyctenium williamsiae

USDA symbol: POWI

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Polyctenium fremontii (S. Watson) Greene var. confertum Rollins (POFRC)   

Washoe Combleaf: A Rare Western Wildflower Worth Protecting Meet Washoe combleaf (Polyctenium williamsiae), one of the West’s most elusive native wildflowers. If you’ve never heard of this plant, you’re not alone – it’s so rare that most gardeners will never encounter it in the wild, let alone in cultivation. What ...

Rare plant alert!

Region: Conservation status by state

Status: S2Q: Status is uncertain but is somewhere between the following rankings: Uncertain taxonomy: ⚘ 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) ⚘ Uncertain taxonomy: ⚘ 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) ⚘ 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. ⚘ 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 ⚘

Region: Conservation status by state

Washoe Combleaf: A Rare Western Wildflower Worth Protecting

Meet Washoe combleaf (Polyctenium williamsiae), one of the West’s most elusive native wildflowers. If you’ve never heard of this plant, you’re not alone – it’s so rare that most gardeners will never encounter it in the wild, let alone in cultivation.

What Makes Washoe Combleaf Special?

This perennial forb belongs to a group of plants that lack woody stems but return year after year from underground parts. Think of it as nature’s ultimate minimalist – it keeps things simple with herbaceous growth that dies back seasonally, then emerges again when conditions are right.

Washoe combleaf has quite the botanical identity crisis, having been known by the synonym Polyctenium fremontii var. confertum in the past. Sometimes plants get shuffled around taxonomically as scientists learn more about their relationships – it’s like getting a family tree update!

Where Does It Call Home?

This native wildflower has chosen some pretty spectacular real estate in the American West, calling California, Nevada, and Oregon home. It’s perfectly adapted to the unique conditions found in these western states, having evolved alongside the region’s other native species over thousands of years.

The Rarity Reality Check

Here’s where things get serious: Washoe combleaf appears to have uncertain conservation status, which often indicates rarity concerns. When we don’t have clear data on a plant’s population status, it’s usually because it’s either extremely rare or found in very specific, limited locations.

Should You Grow Washoe Combleaf?

Here’s the honest truth – you probably shouldn’t try to grow this plant, and here’s why:

  • It’s likely very rare in the wild
  • No cultivation information exists
  • Seeds or plants aren’t commercially available
  • Its specific growing requirements are unknown
  • Attempting to collect from wild populations could harm remaining plants

Better Alternatives for Your Garden

Instead of trying to grow this rare species, consider these fantastic native alternatives that are easier to find and grow:

  • Native penstemons for colorful wildflower displays
  • Local buckwheats for pollinator-friendly blooms
  • Regional lupines for dramatic flower spikes
  • Indigenous asters and sunflowers for late-season color

How You Can Help

The best thing you can do for Washoe combleaf is to support its conservation:

  • Choose common native plants for your garden instead
  • Support organizations working on rare plant conservation
  • If you encounter this plant in the wild, report the location to local botanists
  • Practice Leave No Trace principles when hiking in its native range

The Bottom Line

While Washoe combleaf might not be destined for your garden beds, it serves as a reminder of the incredible diversity hiding in our western landscapes. Sometimes the best way to appreciate a rare plant is to leave it wild and focus our gardening energy on more common natives that can thrive in cultivation while still supporting local ecosystems.

Remember, every native plant in your garden – even the common ones – is making a difference for local wildlife and helping preserve the character of your region’s natural heritage.

Washoe Combleaf

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Dilleniidae

Order

Capparales

Family

Brassicaceae Burnett - Mustard family

Genus

Polyctenium Greene - combleaf

Species

Polyctenium williamsiae Rollins - Washoe combleaf

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