North America Native Plant

Ash Creek Mousetail

Botanical name: Ivesia paniculata

USDA symbol: IVPA

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Ash Creek Mousetail: A Rare California Native Worth Protecting If you’re drawn to unique native plants with a story to tell, Ash Creek mousetail (Ivesia paniculata) might catch your attention. But before you start planning where to plant this California endemic, there’s something important you need to know about its ...

Rare plant alert!

Region: Conservation status by state

Status: S2: Status is uncertain but is somewhere between the following rankings: 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) ⚘

Ash Creek Mousetail: A Rare California Native Worth Protecting

If you’re drawn to unique native plants with a story to tell, Ash Creek mousetail (Ivesia paniculata) might catch your attention. But before you start planning where to plant this California endemic, there’s something important you need to know about its conservation status.

What Makes Ash Creek Mousetail Special

Ash Creek mousetail is a charming perennial forb that forms low rosettes of compound leaves, each divided into multiple small leaflets. During its blooming period, it sends up delicate branched flower clusters (called panicles) adorned with small white to cream-colored flowers. The overall effect is quite elegant—imagine a miniature version of some of our showier native wildflowers, but with its own understated beauty.

As a member of the rose family, this little plant shares some characteristics with more familiar garden favorites, though it’s adapted to much more specialized growing conditions than your typical backyard rose.

Where It Calls Home

Ash Creek mousetail is a true California native, found exclusively within the Golden State’s borders. More specifically, it’s endemic to the Sierra Nevada region, where it has adapted to the unique conditions of high-elevation rocky habitats.

A Plant in Need of Protection

Here’s where things get serious: Ash Creek mousetail has a Global Conservation Status of S2, which means it’s considered Imperiled. This classification indicates the species is at risk due to extreme rarity, with typically only 6 to 20 known occurrences and fewer than 1,000 to 3,000 individual plants remaining in the wild.

What does this mean for gardeners? If you’re interested in growing this species, you should only obtain plants or seeds from reputable sources that practice responsible collection methods and contribute to conservation efforts. Never collect from wild populations, as this could further threaten the species’ survival.

Growing Conditions and Care

If you can source Ash Creek mousetail responsibly, here’s what you need to know about keeping it happy:

  • Drainage is everything: This plant absolutely requires well-draining, rocky or gravelly soil. Think alpine conditions rather than typical garden loam.
  • Sun exposure: Provide full sun to partial shade, mimicking its natural mountain habitat.
  • Water needs: Once established, it prefers dry conditions. Overwatering is likely to be more harmful than underwatering.
  • Climate zones: Best suited for USDA hardiness zones 7-9, reflecting its Sierra Nevada origins.

Garden Role and Design Ideas

Given its specialized needs and conservation status, Ash Creek mousetail isn’t a plant for every garden. However, if you have the right conditions and can source it responsibly, it could be a treasured addition to:

  • Rock gardens that mimic alpine conditions
  • Specialized native plant collections
  • Conservation-focused landscapes
  • Educational gardens highlighting rare California flora

Benefits to Pollinators and Wildlife

The small flowers of Ash Creek mousetail provide nectar and pollen for native bees and other small pollinators. While we don’t have extensive data on all its wildlife interactions, most native Ivesia species support local pollinator communities, making this plant a valuable contributor to biodiversity in appropriate settings.

The Bottom Line

Ash Creek mousetail represents both the beauty and fragility of California’s native flora. While its rarity means it’s not a plant most gardeners will grow, those who are passionate about plant conservation and have appropriate growing conditions might consider it—but only with responsibly sourced material.

If you’re inspired by this plant but can’t obtain it responsibly, consider exploring other California natives that share similar aesthetic qualities but aren’t at conservation risk. Your local native plant society can suggest alternatives that will give you that same connection to California’s unique botanical heritage without putting rare species at further risk.

Remember, every garden is an opportunity to support native ecosystems. Whether you grow rare treasures like Ash Creek mousetail or more common natives, you’re contributing to the preservation of California’s incredible plant diversity.

Ash Creek Mousetail

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

Rosales

Family

Rosaceae Juss. - Rose family

Genus

Ivesia Torr. & A. Gray - mousetail

Species

Ivesia paniculata T.W. Nelson & J.P. Nelson - Ash Creek mousetail

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