North America Native Plant

Sawtooth Bristleweed

Botanical name: Hazardia squarrosa var. obtusa

USDA symbol: HASQO2

Life cycle: perennial

Habit: subshrub

Native status: Native to the lower 48 states  

Synonyms: Haplopappus squarrosus Hook. & Arn. ssp. obtusus (Greene) H.M. Hall (HASQO)   

Sawtooth Bristleweed: A Golden Gem for California Native Gardens If you’re looking to add a splash of golden color to your drought-tolerant garden while supporting local wildlife, let me introduce you to sawtooth bristleweed (Hazardia squarrosa var. obtusa). This charming California native shrub might not have the flashiest name, but ...

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. ⚘

Sawtooth Bristleweed: A Golden Gem for California Native Gardens

If you’re looking to add a splash of golden color to your drought-tolerant garden while supporting local wildlife, let me introduce you to sawtooth bristleweed (Hazardia squarrosa var. obtusa). This charming California native shrub might not have the flashiest name, but it’s a real treasure for gardeners who appreciate low-maintenance plants with big ecological benefits.

What is Sawtooth Bristleweed?

Sawtooth bristleweed is a perennial shrub that’s as hardy as it is beautiful. Like most shrubs, it’s a multi-stemmed woody plant that typically stays under 13-16 feet tall, making it perfect for residential landscapes. This native Californian has been quietly brightening up coastal areas and islands for generations, and now it’s ready to do the same for your garden.

You might also see this plant listed under its scientific synonym, Haplopappus squarrosus ssp. obtusus, but don’t let the botanical names intimidate you – it’s still the same wonderful plant!

Where Does It Come From?

This golden beauty is a true California native, calling the Golden State home exclusively. You’ll find it naturally growing in Southern California’s coastal regions and on the Channel Islands, where it has adapted beautifully to the Mediterranean climate.

Why Your Garden (and Local Wildlife) Will Love It

Here’s where sawtooth bristleweed really shines – it’s like a welcome mat for pollinators! Those cheerful yellow, daisy-like flowers that bloom in late summer and fall are magnets for:

  • Native bees
  • Butterflies
  • Other beneficial insects

The silvery-gray foliage provides year-round interest, creating a lovely backdrop for more colorful plants while adding texture to your landscape. It’s the kind of plant that works beautifully in naturalistic settings, where it can show off its wild, authentic character.

Perfect Garden Matches

Sawtooth bristleweed is a natural fit for:

  • Native plant gardens
  • Mediterranean-style landscapes
  • Xeriscapes (drought-tolerant gardens)
  • Wildlife habitat gardens
  • Coastal gardens

It plays well with other California natives and drought-tolerant plants, serving as either a backdrop shrub or a focal point, depending on your design vision.

Growing Conditions and Care

Here’s the best part – sawtooth bristleweed is refreshingly low-maintenance! This shrub thrives in USDA hardiness zones 9-11, making it perfect for mild winter areas.

What it needs:

  • Full sun (it loves those California rays!)
  • Well-draining soil
  • Minimal water once established

Care tips:

  • Water regularly during the first year to help it get established
  • After that, it’s quite drought tolerant
  • Give it a light pruning after flowering to maintain shape
  • Avoid overwatering – this plant prefers to stay on the dry side

A Special Note About Conservation

While sawtooth bristleweed isn’t critically endangered, it does have a conservation status that suggests we should be mindful about its populations in the wild. If you’re planning to add this beauty to your garden, make sure you source it from reputable native plant nurseries that propagate their plants responsibly rather than collecting from wild populations.

The Bottom Line

Sawtooth bristleweed is one of those plants that proves native doesn’t mean boring. With its golden flowers, drought tolerance, and pollinator appeal, it’s a smart choice for California gardeners who want to create beautiful, sustainable landscapes. Plus, you’ll have the satisfaction of knowing you’re supporting local ecosystems while enjoying a truly low-maintenance addition to your garden.

Ready to give this California native a try? Your local pollinators will thank you, and your water bill will too!

Sawtooth Bristleweed

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

Hazardia Greene - bristleweed

Species

Hazardia squarrosa (Hook. & Arn.) Greene - sawtooth goldenbush

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