North America Native Plant

Oahu Beggarticks

Botanical name: Bidens populifolia

USDA symbol: BIPO2

Life cycle: perennial

Habit: subshrub

Native status: Native to Hawaii  

Oahu Beggarticks: A Critically Endangered Hawaiian Native Worth Protecting Meet the Oahu beggarticks (Bidens populifolia), a small but mighty native Hawaiian shrub that’s fighting for survival on its home island. This unassuming perennial plant might not win any beauty contests, but it holds incredible ecological significance as one of Hawaii’s ...

Rare plant alert!

Region: Conservation status by state

Status: S1: Status is uncertain but is somewhere between the following rankings: 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) ⚘

Oahu Beggarticks: A Critically Endangered Hawaiian Native Worth Protecting

Meet the Oahu beggarticks (Bidens populifolia), a small but mighty native Hawaiian shrub that’s fighting for survival on its home island. This unassuming perennial plant might not win any beauty contests, but it holds incredible ecological significance as one of Hawaii’s most endangered native species.

What Makes Oahu Beggarticks Special

Don’t let the name fool you – this isn’t your typical weedy beggarticks that hitchhikes on your socks during nature walks. Bidens populifolia is a rare gem that grows as a low, compact shrub, typically staying under 1.5 feet tall and never exceeding 3 feet at maturity. Its modest stature belies its important role in Hawaii’s native ecosystem.

This perennial produces small yellow flowers characteristic of the sunflower family, creating subtle but charming displays when in bloom. The simple leaves and branching structure give it a delicate, almost wispy appearance that adds texture to native plant gardens.

Where You’ll Find This Rare Beauty

Oahu beggarticks is endemic to Hawaii, specifically found only on the island of Oahu. This extremely limited distribution is one of the reasons why this plant is in such dire straits today.

A Plant in Crisis: Understanding Its Rarity

Important Conservation Alert: Bidens populifolia has a Global Conservation Status of S1, meaning it’s critically imperiled. With typically 5 or fewer occurrences and very few remaining individuals (fewer than 1,000), this plant is teetering on the brink of extinction. This extreme rarity makes it especially vulnerable to complete disappearance from the wild.

Should You Grow Oahu Beggarticks?

Here’s where things get tricky. While we absolutely want to encourage the cultivation of native Hawaiian plants, Oahu beggarticks requires a very careful approach:

  • Only use responsibly sourced material: Never collect from wild populations
  • Work with conservation organizations: Partner with botanical gardens or conservation groups
  • Focus on habitat restoration: Best suited for legitimate conservation and restoration projects
  • Consider alternatives: For home gardens, explore other native Hawaiian Bidens species that are less endangered

Growing Conditions and Care

If you’re involved in conservation efforts and have access to responsibly sourced plants, Oahu beggarticks thrives in:

  • Climate: USDA hardiness zones 10-11 (tropical and subtropical)
  • Sunlight: Partial to full sun exposure
  • Soil: Well-draining soils that don’t stay waterlogged
  • Water: Moderate watering needs – not too wet, not too dry

Garden Design Role

In the right setting, Oahu beggarticks works beautifully as:

  • A low border plant in native Hawaiian gardens
  • Part of mixed native shrub plantings
  • An educational specimen in botanical collections
  • A conservation showcase in restoration landscapes

Pollinator and Wildlife Benefits

While small in stature, this native shrub provides valuable resources for Hawaii’s native insects and other pollinators. Its flowers offer nectar and pollen, supporting the intricate web of native Hawaiian biodiversity.

The Bottom Line

Oahu beggarticks represents both the beauty and fragility of Hawaii’s native flora. While most home gardeners should focus on other native Hawaiian plants that aren’t critically endangered, this species deserves our respect and protection. If you’re passionate about Hawaiian native plant conservation, consider supporting organizations working to protect and propagate this remarkable little shrub.

Remember: every native plant we lose is a piece of Hawaii’s natural heritage that disappears forever. Let’s work together to ensure that future generations can still marvel at the diversity of Hawaii’s unique native flora.

Oahu Beggarticks

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

Bidens L. - beggarticks

Species

Bidens populifolia Sherff - Oahu beggarticks

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