North America Native Plant

Acuminate Orthothecium Moss

Botanical name: Orthothecium acuminatum

USDA symbol: ORAC

Habit: nonvascular

Native status: Native to North America  

Synonyms: Holmgrenia acuminata (Bryhn) Grout (HOAC3)   

Acuminate Orthothecium Moss: A Delicate Native Bryophyte for Your Garden Meet the acuminate orthothecium moss (Orthothecium acuminatum), a charming little bryophyte that’s quietly making its mark in native gardens across North America. This delicate moss might not grab headlines like flashy flowers, but it brings its own subtle beauty and ...

Rare plant alert!

Region: Conservation status by state

Status: S1S3: 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) ⚘ 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 ⚘

Acuminate Orthothecium Moss: A Delicate Native Bryophyte for Your Garden

Meet the acuminate orthothecium moss (Orthothecium acuminatum), a charming little bryophyte that’s quietly making its mark in native gardens across North America. This delicate moss might not grab headlines like flashy flowers, but it brings its own subtle beauty and ecological value to the right garden setting.

What Exactly Is Acuminate Orthothecium Moss?

Don’t let the fancy name intimidate you! Acuminate orthothecium moss is simply a small, terrestrial moss that belongs to the bryophyte family – those fascinating green plants that include mosses, liverworts, and hornworts. Unlike your typical garden plants, this little guy doesn’t have true roots, stems, or leaves in the traditional sense. Instead, it’s perfectly designed to absorb moisture and nutrients directly from the air and surfaces around it.

What makes this moss particularly interesting is its growth habit. Rather than growing directly in soil like most plants, it prefers to attach itself to solid surfaces like rocks, fallen logs, or even living tree bark. Think of it as nature’s way of carpeting hard surfaces with soft, green cushions.

Native Status and Where You’ll Find It

Here’s something to feel good about: acuminate orthothecium moss is a true North American native. This means it has evolved alongside our local ecosystems and plays a natural role in the environment. While the exact geographical distribution isn’t fully documented, this moss typically thrives in the cooler, more mountainous regions of the continent.

A Word About Rarity

Before you get too excited about adding this moss to your collection, there’s something important to know. Acuminate orthothecium moss has a conservation status of S1S3, which indicates it may be uncommon to rare in certain areas. If you’re lucky enough to spot this moss in the wild, it’s best to admire it from a distance rather than harvesting it for your garden.

Identifying Acuminate Orthothecium Moss

Spotting this moss in the wild (or confirming you’ve found it) requires a keen eye for detail. Here’s what to look for:

  • Small, pointed leaves that give the moss its acuminate name (which literally means tapering to a point)
  • Forms neat, compact cushions or mats on hard surfaces
  • Typically grows on rocks, dead wood, or tree bark rather than directly in soil
  • Bright to deep green coloration when moist
  • May appear more brownish when dry

Benefits for Your Garden Ecosystem

While acuminate orthothecium moss might not attract butterflies or hummingbirds like flowering plants do, it still contributes to garden health in subtle ways. Mosses help retain moisture in the environment, create microhabitats for tiny creatures, and add textural interest to naturalistic garden designs.

This moss works particularly well in:

  • Rock gardens where it can naturally colonize stone surfaces
  • Woodland or shade gardens that mimic forest floor conditions
  • Alpine-style gardens that replicate mountain environments
  • Rain gardens or areas with consistent moisture

Growing Conditions and Care

If you’re interested in encouraging mosses like this one in your garden (rather than introducing collected specimens), focus on creating the right conditions:

  • Provide plenty of shade – direct sunlight can quickly dry out delicate moss tissues
  • Maintain consistent moisture without creating soggy conditions
  • Include rocks, logs, or other hard surfaces where moss can attach
  • Ensure good air circulation to prevent fungal issues
  • Be patient – mosses grow slowly and establish gradually

The Bottom Line

Acuminate orthothecium moss represents one of nature’s more understated beauties. While its rarity means you shouldn’t collect it from the wild, you can certainly appreciate it when you encounter it and create conditions in your garden that might naturally attract similar native mosses. Sometimes the smallest plants make the biggest difference in creating authentic, sustainable native landscapes.

Remember, the best approach with rare native species like this one is to observe, appreciate, and protect rather than collect. Your garden can still benefit from the moss community by providing the right habitat conditions and letting nature work its magic naturally.

Acuminate Orthothecium Moss

Classification

Group

Moss

Kingdom

Plantae - Plants

Subkingdom
Superdivision
Division

Bryophyta - Mosses

Subdivision

Musci

Class

Bryopsida - True mosses

Subclass

Bryidae

Order

Hypnales

Family

Hypnaceae Schimp.

Genus

Orthothecium Schimp. - orthothecium moss

Species

Orthothecium acuminatum Bryhn - acuminate orthothecium moss

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