North America Native Plant

Mannagrass

Botanical name: Glyceria ×gatineauensis

USDA symbol: GLGA

Life cycle: perennial

Habit: grass

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

Mannagrass (Glyceria ×gatineauensis): A Rare Native Hybrid Worth Knowing About If you’re a native plant enthusiast who loves discovering botanical rarities, Glyceria ×gatineauensis might just pique your interest. This perennial mannagrass is one of those special plants that botanists get excited about – a naturally occurring hybrid that’s as elusive ...

Mannagrass (Glyceria ×gatineauensis): A Rare Native Hybrid Worth Knowing About

If you’re a native plant enthusiast who loves discovering botanical rarities, Glyceria ×gatineauensis might just pique your interest. This perennial mannagrass is one of those special plants that botanists get excited about – a naturally occurring hybrid that’s as elusive as it is intriguing.

What Makes This Mannagrass Special?

The × in Glyceria ×gatineauensis tells us we’re dealing with a hybrid – nature’s own plant breeding experiment. This perennial graminoid (that’s fancy talk for grass-like plant) belongs to the mannagrass family, a group known for their love of wet feet and important ecological roles in aquatic environments.

As a native species to both Canada and the lower 48 United States, this mannagrass has earned its place in North American ecosystems naturally, without any help from human introduction.

Where Does It Call Home?

Currently documented in Quebec and New York, Glyceria ×gatineauensis has a remarkably limited geographic range. This restricted distribution is typical of many hybrid species, which often occur where the parent species’ ranges overlap.

Should You Try Growing This Mannagrass?

Here’s where things get a bit complicated. While this native mannagrass would theoretically be a wonderful addition to wetland gardens or naturalized water features, its extreme rarity makes it practically unavailable to home gardeners. You’re unlikely to find it at your local native plant sale or through commercial sources.

The Reality Check

For most gardeners interested in native grasses for wet areas, you’ll want to consider more readily available alternatives such as:

  • Other Glyceria species that are more common
  • Native sedges (Carex species)
  • Rice cutgrass (Leersia oryzoides)
  • Wild rice (Zizania species)

These alternatives will give you similar ecological benefits and aesthetic appeal while being much more obtainable and better documented in terms of growing requirements.

Why It Matters

Even though you probably won’t be planting Glyceria ×gatineauensis in your garden, knowing about rare native species like this one helps us appreciate the incredible diversity of our native flora. Every species, no matter how uncommon, plays a role in the complex web of native ecosystems.

As a graminoid, this mannagrass would typically provide habitat for various insects, contribute to soil stability in wet areas, and serve as part of the food web in aquatic and semi-aquatic environments – if you could find it to plant!

The Bottom Line

While Glyceria ×gatineauensis represents the fascinating world of native plant hybrids, it’s more of a botanical curiosity than a practical garden choice. If you’re passionate about supporting native ecosystems through your plant choices, focus on readily available native grasses and sedges that can provide similar ecological benefits without the sourcing challenges.

Sometimes the best way to honor rare native species is simply to appreciate that they exist and support conservation efforts that protect the habitats where these botanical treasures can continue to thrive naturally.

Mannagrass

Classification

Group

Monocot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Liliopsida - Monocotyledons

Subclass

Commelinidae

Order

Cyperales

Family

Poaceae Barnhart - Grass family

Genus

Glyceria R. Br. - mannagrass

Species

Glyceria ×gatineauensis Bowden [melicaria × striata] - mannagrass

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