North America Native Plant

Forest Danafern

Botanical name: Danaea urbanii

USDA symbol: DAUR2

Life cycle: perennial

Habit: forb

Native status: Native to Puerto Rico  

Forest Danafern: A Mysterious Puerto Rican Native Worth Knowing If you’re a fern enthusiast with a penchant for rare and exotic species, you might have stumbled across the intriguing forest danafern (Danaea urbanii). This lesser-known fern is a true Puerto Rican native that calls the island’s wetlands home, though don’t ...

Forest Danafern: A Mysterious Puerto Rican Native Worth Knowing

If you’re a fern enthusiast with a penchant for rare and exotic species, you might have stumbled across the intriguing forest danafern (Danaea urbanii). This lesser-known fern is a true Puerto Rican native that calls the island’s wetlands home, though don’t expect to find it at your local garden center anytime soon!

What Exactly Is Forest Danafern?

Forest danafern belongs to the ancient Marattiaceae family of ferns, a group that has been around since the time of dinosaurs. These aren’t your typical backyard ferns – they’re part of an elite club of primitive ferns that have some pretty unique characteristics. While many sources might classify it differently, Danaea urbanii is indeed a true fern species that has adapted to life in Puerto Rico’s unique ecosystem.

This perennial fern has made Puerto Rico its exclusive home, where it thrives in the island’s lush, humid environment. As an obligate wetland species, it’s perfectly content living with its feet wet – in fact, it almost always occurs in wetland areas throughout the Caribbean region.

Where You’ll Find This Elusive Fern

Forest danafern is endemic to Puerto Rico, meaning you won’t find it growing wild anywhere else in the world. This makes it a pretty special plant from a conservation standpoint, though it also means your chances of encountering one are limited unless you’re exploring Puerto Rico’s wetland areas.

Is Forest Danafern Right for Your Garden?

Here’s where things get a bit tricky. While forest danafern sounds like it could be an amazing addition to a native Puerto Rican garden or a specialized fern collection, there are several important considerations:

  • Availability: This species is extremely difficult to find in cultivation, and responsible sourcing is crucial if you do locate it
  • Specialized needs: As an obligate wetland species, it requires consistently moist to wet conditions
  • Climate requirements: It’s adapted specifically to Puerto Rico’s tropical climate
  • Conservation concern: Limited distribution means any cultivation should prioritize conservation

What We Know About Growing Conditions

Based on its natural habitat, forest danafern would likely prefer:

  • Consistently moist to wet soil conditions
  • High humidity levels
  • Warm, tropical temperatures year-round
  • Partial to full shade
  • Rich, organic soil similar to what you’d find in wetland areas

Benefits to Your Garden Ecosystem

While specific wildlife benefits for forest danafern aren’t well-documented, ferns in general provide several ecosystem services:

  • Habitat and shelter for small wildlife
  • Soil stabilization, especially important in wetland areas
  • Natural water filtration in wet garden areas
  • Unique texture and form in shade gardens

The Bottom Line

Forest danafern represents the kind of specialized, endemic species that makes Puerto Rico’s flora so unique. While it’s not a practical choice for most gardeners due to its rarity and specialized needs, it serves as a reminder of the incredible diversity hidden in our world’s wetland ecosystems.

If you’re in Puerto Rico and interested in native wetland gardening, focus on more readily available native ferns and wetland plants that can provide similar ecological benefits without the conservation concerns. And who knows? Maybe increased interest in Puerto Rico’s native flora will eventually lead to more research and responsible cultivation of unique species like the forest danafern.

For now, this mysterious fern remains one of nature’s well-kept secrets, quietly doing its part in Puerto Rico’s wetland ecosystems while most of the world remains unaware of its existence.

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 work and fewer inputs. But the simplicity of this catchphrase conceals how tricky plant selection is. While tags 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. Surprisingly, many popular landscape plants are wetland species! And what may be a wetland plant in one area, in another it might thrive in drier conditions. Also, it helps you make smarter gardening choices and grow healthy plants with less care and feeding, saving you time, frustration, and money while producing an attractive garden with greater ecological benefits.

Regions
Status
Moisture Conditions

Caribbean

OBL

Obligate Wetland - Plants with this status almost always occurs in wetlands

Forest Danafern

Classification

Group

Fern

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision
Division

Pteridophyta - Ferns

Subdivision
Class

Filicopsida

Subclass
Order

Marattiales

Family

Marattiaceae Kaulf. - Vessel Fern family

Genus

Danaea Sm. - danafern

Species

Danaea urbanii Maxon - forest danafern

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