North America Native Plant

Quillwort

Botanical name: Isoetes ×eatonii

USDA symbol: ISEA

Life cycle: perennial

Habit: grass

Native status: Native to Canada âš˜ Native to the lower 48 states  

Synonyms: Isoetes eatonii R. Dodge var. gravesii (A.A. Eaton) Clute, nom. dub. (ISEAG)  âš˜  Isoetes gravesii A.A. Eaton (ISGR)   

Discovering Eaton’s Quillwort: A Rare Aquatic Native Worth Knowing If you’ve ever wondered about those mysterious grass-like plants growing in shallow pond edges or wetland margins, you might have encountered a quillwort. Today, we’re diving into the fascinating world of Eaton’s quillwort (Isoetes ×eatonii), a unique native aquatic plant that’s ...

Rare plant alert!

Region: Conservation status by state

Status: S1Q: Status is uncertain but is somewhere between the following rankings: Uncertain taxonomy: ⚘ 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) ⚘

Discovering Eaton’s Quillwort: A Rare Aquatic Native Worth Knowing

If you’ve ever wondered about those mysterious grass-like plants growing in shallow pond edges or wetland margins, you might have encountered a quillwort. Today, we’re diving into the fascinating world of Eaton’s quillwort (Isoetes ×eatonii), a unique native aquatic plant that’s both incredibly specialized and surprisingly rare.

What Exactly Is Eaton’s Quillwort?

Don’t let the name fool you – quillworts aren’t actually related to grasses at all! Eaton’s quillwort is a perennial aquatic plant that belongs to an ancient group of plants called lycopods. These living fossils have been around for hundreds of millions of years, making them some of the oldest plant lineages on Earth.

This particular species is actually a hybrid, which explains the × in its botanical name Isoetes ×eatonii. Like other quillworts, it has a distinctive appearance with narrow, quill-like leaves that emerge from a bulbous base, creating small underwater or semi-aquatic rosettes.

Where You’ll Find This Native Treasure

Eaton’s quillwort is native to both Canada and the lower 48 states, with a range that includes Ontario and several northeastern U.S. states: Connecticut, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, and Vermont. It’s a true northeasterner that thrives in the cooler climates of this region.

A Wetland Specialist

Here’s something fascinating about Eaton’s quillwort – it’s classified as an Obligate Wetland species across its entire range. This means it almost always occurs in wetlands, making it one of nature’s most reliable indicators of healthy aquatic ecosystems. You’ll typically find it in:

  • Shallow pond margins
  • Lake shores
  • Seasonal pools
  • Bog edges
  • Other permanently or seasonally flooded areas

Is Eaton’s Quillwort Right for Your Garden?

Before we get too excited about adding this unique native to our landscapes, there’s something important to consider: Eaton’s quillwort has a Global Conservation Status of S1Q, which indicates it’s quite rare and its status is somewhat uncertain. This rarity makes it a plant that requires special consideration.

If you’re thinking about incorporating this species into your garden, here are some key points to consider:

Benefits to Your Garden Ecosystem

While quillworts don’t offer the flashy flowers that attract pollinators, they do provide unique ecological benefits:

  • Excellent for creating authentic wetland habitats
  • Helps stabilize muddy pond edges and shallow water areas
  • Provides habitat for aquatic invertebrates
  • Adds prehistoric charm to water gardens
  • Requires minimal maintenance once established

Growing Conditions and Care

If you decide to work with Eaton’s quillwort, understanding its specific needs is crucial for success:

  • Water requirements: Needs consistent moisture or shallow standing water
  • Soil: Prefers muddy, organic-rich substrates
  • Light: Thrives in full sun to partial shade
  • Climate: Hardy in USDA zones 3-7, matching its native range
  • Maintenance: Very low once established in suitable conditions

A Word of Caution: Responsible Sourcing

Given the rare status of Eaton’s quillwort, it’s essential to source any plants responsibly. Never collect from wild populations, and only purchase from reputable nurseries that propagate their own stock or work with conservation programs. Better yet, consider focusing on creating habitat that might naturally attract this and other native wetland species.

How to Identify Eaton’s Quillwort

If you’re exploring wetlands in the northeastern states or Ontario, here’s how to spot this unique plant:

  • Look for small rosettes of narrow, grass-like leaves
  • Leaves are typically 2-8 inches long and very slender
  • Plants grow from a bulbous base partially buried in mud
  • Found in or at the edges of shallow water
  • Often grows alongside other wetland plants like sedges and rushes

The Bottom Line

Eaton’s quillwort represents something special in the plant world – a living link to ancient ecosystems and a indicator of healthy wetlands. While its rarity means it’s not a casual garden addition, understanding and appreciating these unique natives helps us become better stewards of our local ecosystems. If you’re lucky enough to spot one in the wild, take a moment to appreciate this remarkable survivor from the deep past!

For most gardeners interested in native aquatic plants, consider exploring other native wetland species that are more readily available and less conservation-sensitive, while still supporting the ecosystem services that make plants like Eaton’s quillwort so valuable.

Quillwort

Classification

Group

Quillwort

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision
Division

Lycopodiophyta - Lycopods

Subdivision
Class

Lycopodiopsida

Subclass
Order

Isoetales

Family

Isoetaceae Dumort. - Quillwort family

Genus

Isoetes L. - quillwort

Species

Isoetes ×eatonii R. Dodge (pro sp.) [engelmannii × tenella] - quillwort

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