North America Native Plant

Forest Sandmat

Botanical name: Chamaesyce clusiifolia

USDA symbol: CHCL3

Life cycle: perennial

Habit: vine

Native status: Native to Hawaii  

Synonyms: Anisophyllum nodosum Klotzsch & Garcke (ANNO3)  âš˜  Chamaesyce forbesii (Sherff) Croizat & O. Deg. (CHFO5)  âš˜  Euphorbia clusiifolia Hook. & Arn. (EUCL3)  âš˜  Euphorbia forbesii Sherff (EUFO)   

Forest Sandmat: A Rare Hawaiian Native Worth Protecting in Your Garden If you’re passionate about native Hawaiian plants and want to support local biodiversity, forest sandmat (Chamaesyce clusiifolia) might just be the unassuming hero your garden needs. This perennial shrub may not win any beauty contests with its tiny flowers ...

Rare plant alert!

Region: Conservation status by state

Status: S3: Status is uncertain but is somewhere between the following rankings: 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 ⚘

Forest Sandmat: A Rare Hawaiian Native Worth Protecting in Your Garden

If you’re passionate about native Hawaiian plants and want to support local biodiversity, forest sandmat (Chamaesyce clusiifolia) might just be the unassuming hero your garden needs. This perennial shrub may not win any beauty contests with its tiny flowers and modest appearance, but it packs a punch when it comes to ecological value and cultural significance.

What Makes Forest Sandmat Special?

Forest sandmat is a true Hawaiian endemic, meaning it exists nowhere else on Earth except in the beautiful Hawaiian Islands. This small shrub typically grows as a multi-stemmed woody plant, usually staying under 13-16 feet tall, though it often remains much more compact in garden settings. Don’t let its humble appearance fool you – this little plant is a survivor that has adapted perfectly to island life.

Where Does Forest Sandmat Call Home?

You’ll find forest sandmat exclusively in Hawaii, where it has made its home across multiple islands. As a facultative upland species, it typically prefers non-wetland areas but can occasionally pop up in wetter spots when conditions are right.

Why You Should (Carefully) Consider Growing Forest Sandmat

Important Conservation Note: Before we dive into the growing details, here’s something crucial to know – forest sandmat has a Global Conservation Status of S3, meaning it’s considered vulnerable. With only an estimated 21-100 occurrences remaining in the wild, this plant needs our help. If you decide to grow it, please only source it from reputable native plant nurseries that propagate responsibly.

Here’s why forest sandmat deserves a spot in the right garden:

  • Native heritage: Supporting truly native Hawaiian species helps preserve the islands’ unique botanical legacy
  • Low maintenance: Once established, it’s quite drought tolerant and doesn’t demand constant attention
  • Ecological value: While not a major pollinator magnet, its small flowers can attract beneficial native insects
  • Erosion control: Its growth habit makes it useful for stabilizing soil in appropriate locations

Growing Conditions and Care

Forest sandmat is surprisingly adaptable for such a rare plant. Here’s what it needs to thrive:

  • Climate: USDA zones 10-11 (basically, if you can grow it outdoors year-round in Hawaii, you’re golden)
  • Sunlight: Full sun to partial shade – it’s flexible!
  • Soil: Well-draining soil is non-negotiable. It won’t tolerate soggy feet
  • Water: Drought tolerant once established, but appreciates occasional watering during dry spells

Perfect Garden Situations for Forest Sandmat

This native beauty shines in:

  • Native Hawaiian plant gardens
  • Xerophytic (dry-loving) landscapes
  • Coastal gardens where salt tolerance is valued
  • Restoration projects aimed at preserving native ecosystems
  • Naturalistic landscapes that mimic Hawaii’s original plant communities

Planting and Care Tips

Growing forest sandmat successfully is all about getting the basics right:

  • Start small: Young plants establish better than large specimens
  • Prepare the soil: Ensure excellent drainage – add gravel or sand if your soil holds water
  • Water wisely: Water regularly the first year, then back off as it establishes
  • Mulch carefully: A light mulch can help, but don’t pile it against the stem
  • Prune minimally: Light pruning to maintain shape is fine, but this isn’t a plant that needs heavy cutting back

The Bottom Line

Forest sandmat isn’t going to stop traffic with spectacular blooms or dramatic foliage, but for gardeners committed to preserving Hawaii’s botanical heritage, it’s absolutely worth growing. Its rarity makes it a special addition that connects your garden to the islands’ unique natural history. Just remember – with great rarity comes great responsibility. Only source this plant from reputable nurseries, and consider yourself a conservation gardener helping to keep this species around for future generations.

If you can provide well-draining soil and are gardening in tropical conditions, forest sandmat could be the quiet conservation hero your native garden has been waiting for.

Forest Sandmat

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

Euphorbiales

Family

Euphorbiaceae Juss. - Spurge family

Genus

Chamaesyce Gray - sandmat

Species

Chamaesyce clusiifolia (Hook. & Arn.) Arthur - forest sandmat

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