Native Plants

Clubmoss

Huperzia ×erubescens

USDA symbol: HUER2

perennial subshrub

Hawaii: native

If you’ve ever wandered through Hawaii’s lush forests and spotted something that looks like a tiny, primitive Christmas tree growing without soil, you might have encountered one of nature’s most ancient plant groups – the clubmosses. Today, we’re diving into the world of Huperzia ×erubescens, a unique hybrid clubmoss that ...

Understanding Clubmoss: The Fascinating Huperzia ×erubescens

If you’ve ever wandered through Hawaii’s lush forests and spotted something that looks like a tiny, primitive Christmas tree growing without soil, you might have encountered one of nature’s most ancient plant groups – the clubmosses. Today, we’re diving into the world of Huperzia ×erubescens, a unique hybrid clubmoss that calls Hawaii home.

What Exactly Is This Plant?

Despite its common name clubmoss, Huperzia ×erubescens isn’t actually a moss at all! It’s what botanists call a lycopod – an ancient group of vascular plants that have been around for about 400 million years. Think of them as living fossils that give us a glimpse into what Earth’s plant life looked like long before flowers even existed.

This particular species is a hybrid (notice that little × in its name?), which means it’s the result of two different Huperzia species crossing paths. It’s a perennial plant that grows as what’s technically called a forb herb – basically, it’s a vascular plant without any woody stems above ground.

Where You’ll Find It

Huperzia ×erubescens is exclusively native to Hawaii, making it a truly special island endemic. You won’t find this little green gem growing naturally anywhere else in the world.

  • Species observed
  • No observations

What Does It Look Like?

Clubmosses have a distinctive appearance that sets them apart from true mosses and other plants. They typically feature small, needle-like leaves arranged in spirals around upright or trailing stems, giving them that miniature evergreen tree appearance. Since this is a hybrid species with limited documented information, specific details about its exact appearance can vary.

Is It Good for Gardens?

Here’s where things get a bit tricky. While clubmosses can be fascinating additions to specialized gardens, Huperzia ×erubescens presents some unique challenges:

  • It’s classified as a facultative wetland plant, meaning it usually grows in very moist to wet conditions
  • As a hybrid species native only to Hawaii, it likely has very specific growing requirements
  • Limited cultivation information is available for this particular hybrid
  • It doesn’t produce flowers, so it won’t attract pollinators like bees or butterflies

The Conservation Angle

Since this is a Hawaiian endemic hybrid with unknown rarity status, it’s worth considering the conservation implications. If you’re lucky enough to encounter this plant in Hawaii, it’s best admired from a distance rather than collected. Hawaii’s native flora faces numerous threats, and every individual plant plays a role in maintaining these unique ecosystems.

For the Curious Gardener

If you’re fascinated by ancient plants and live in a suitable climate, you might consider other, more readily available clubmoss species for your garden. Many Huperzia species appreciate:

  • High humidity
  • Filtered or dappled sunlight
  • Consistently moist (but not waterlogged) growing medium
  • Good air circulation

The Bottom Line

Huperzia ×erubescens is more of a look but don’t touch plant – a fascinating piece of Hawaii’s natural heritage that’s best appreciated in its native habitat. While it might not be the ideal garden plant for most of us, understanding and appreciating these ancient survivors helps us connect with the incredible diversity of plant life that has shaped our planet.

If you’re interested in growing unusual, primitive plants in your garden, consider researching other lycopods or native alternatives in your area. There’s something deeply satisfying about growing plants that connect us to Earth’s ancient botanical history – even if they’re not quite as rare and special as this Hawaiian hybrid.

Huperzia ×erubescens is also known as...

Often we refer to plants by their common names. When shopping for plants the scientific name is the best way to positively identify the plant species you desire. But some plants have more than one name! While it doesn't happen often, nurseries might display one name while you're searching for another. Huperzia ×erubescens is also known as:

Lycopodium erubescens | USDA symbol: LYER
Urostachys erubescens Herter ex | USDA symbol: URER

Why do some plants have more than one name? Over time plant species may be renamed for a few reasons:

  1. Botanists in different regions named the same plant without knowing it had already been classified.
  2. A species was reclassified after scientific advances in, for example, DNA analysis.
  3. Slight variations within a species are sometimes mistakenly identified as entirely new species.

Wetland Status

The rule of seasoned gardeners and landscapers is to choose the "right plant for the right place" — matching plants to their ideal growing conditions, so they'll thrive with less care and fewer inputs. But the simplicity of this catchphrase conceals how tricky plant selection can be if you don't have the right information. While tags on nursery plants list watering requirements, there's more to the story.

Knowing a plant's wetland status can simplify the process by revealing the interaction between plants, water, and soil. You might be surprised to learn that popular landscape plants are wetland species! And what may be a wetland plant in one area, in another it might thrive in drier conditions. The table below gives insight into the preferred growing conditions of this plant throughout its geographical distribution.

Region
Preferred Habitat

Hawaii ()

Facultative Wetland
Wetland Glossary
Obligate Wetland
Facultative Wetland
Facultative
Facultative Upland
Obligate Upland
Almost always occurs in wetlands
Usually occurs in wetlands but may occur in non-wetlands
Can occur in wetlands and non-wetlands
Usually occurs in non-wetlands but may occur in wetlands
Almost never occurs in wetlands

Classification

Group: Lycopod
Kingdom: Plantae - Plants
Subkingdom: Tracheobionta - Vascular plants
Division: Lycopodiophyta - Lycopods
Class: Lycopodiopsida
Order: Lycopodiales
Family: Lycopodiaceae P. Beauv. ex Mirb. - Club-moss family
Genus: Huperzia Bernh. - clubmoss

Species: Huperzia ×erubescens (Brack.) Holub (pro sp.) [haleakalae × somae] - clubmoss

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