North America Native Plant

Puerto Rico Halberd Fern

Botanical name: Tectaria estremeriana

USDA symbol: TEES

Life cycle: perennial

Habit: forb

Native status: Native to Puerto Rico  

Puerto Rico Halberd Fern: A Critically Rare Treasure of the Caribbean Hidden in the lush landscapes of Puerto Rico grows one of the island’s most precious botanical treasures—the Puerto Rico halberd fern (Tectaria estremeriana). This remarkable native fern represents more than just another green addition to the forest floor; it’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) ⚘

Puerto Rico Halberd Fern: A Critically Rare Treasure of the Caribbean

Hidden in the lush landscapes of Puerto Rico grows one of the island’s most precious botanical treasures—the Puerto Rico halberd fern (Tectaria estremeriana). This remarkable native fern represents more than just another green addition to the forest floor; it’s a critically imperiled species that tells the story of Caribbean biodiversity and conservation challenges.

What Makes This Fern Special?

The Puerto Rico halberd fern belongs to the Tectaria genus, a group of tropical ferns known for their distinctive frond shapes. As its common name suggests, this perennial fern is endemic to Puerto Rico, meaning it naturally occurs nowhere else on Earth. This makes it an irreplaceable part of the island’s unique ecological heritage.

Unlike the woody trees and shrubs that dominate many landscapes, this fern is classified as a forb—a non-woody vascular plant that persists year after year through underground structures, sending up fresh fronds seasonally.

Where Does It Grow?

The Puerto Rico halberd fern is found exclusively in Puerto Rico, where it clings to existence in what are likely very specific habitat conditions. Its extremely limited distribution contributes to its precarious conservation status.

A Species on the Brink

Here’s where the story becomes both fascinating and concerning. The Puerto Rico halberd fern carries a Global Conservation Status of S1, which translates to Critically Imperiled. This designation means the species is at extreme risk of disappearing forever, typically with only five or fewer known locations and fewer than 1,000 individual plants remaining in the wild.

This rarity status puts the Puerto Rico halberd fern in the same category as some of the world’s most endangered species. Every individual plant becomes precious when you’re working with numbers this small.

Should You Try to Grow It?

While the idea of cultivating rare native plants might seem appealing to dedicated gardeners, the Puerto Rico halberd fern presents a unique situation. Its critically imperiled status means that any cultivation efforts should only be undertaken with:

  • Plants sourced through legitimate conservation programs
  • Proper permits and documentation
  • Collaboration with botanical institutions or conservation organizations
  • A commitment to conservation rather than just garden aesthetics

For most home gardeners, the best way to support this species is through conservation donations and habitat protection rather than attempting to grow it personally.

Alternative Native Ferns for Puerto Rican Gardens

If you’re interested in supporting Puerto Rico’s native plant heritage in your garden, consider these more readily available native fern alternatives:

  • Other Tectaria species that may be less rare
  • Native tree ferns suitable for tropical landscapes
  • Indigenous ground ferns that can thrive in cultivation

Check with local native plant societies or botanical gardens for recommendations on native ferns that can be responsibly cultivated while supporting local ecosystems.

The Bigger Picture

The story of the Puerto Rico halberd fern reminds us that not every beautiful native plant is meant for our gardens. Sometimes, the most meaningful way to appreciate a species is to support its protection in the wild and learn about the complex web of factors that make certain plants so rare and precious.

By understanding and respecting the conservation needs of critically imperiled species like Tectaria estremeriana, we become better stewards of the incredible biodiversity that makes places like Puerto Rico so special. Every rare fern that persists is a victory for conservation and a gift for future generations to discover and protect.

Puerto Rico Halberd Fern

Classification

Group

Fern

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision
Division

Pteridophyta - Ferns

Subdivision
Class

Filicopsida

Subclass
Order

Polypodiales

Family

Dryopteridaceae Herter - Wood Fern family

Genus

Tectaria Cav. - halberd fern

Species

Tectaria estremeriana Proctor & A.M. Evans - Puerto Rico halberd fern

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