In the mountains, some of the most interesting plants are easy to overlook. They may not form large fields of color or have the towering presence of a tree, but they can tell us a great deal about the landscape around them. Grass of Parnassus is one of those plants.
Despite its name, Grass of Parnassus is not actually grass. It is a delicate wildflower that grows in moist, often open habitats and is especially noticeable in the mountains during late summer and fall. Its small white flowers can seem almost too delicate for the rugged landscape where they grow.
In the Great Smoky Mountains, finding Grass of Parnassus can be a sign that you are in a unique kind of habitat.
Not Really Grass
Grass of Parnassus (Parnassia asarifolia) gets its common name from its narrow, grass-like leaves. The plant itself, however, belongs to the genus Parnassia and is part of the family Celastraceae, the same family that includes plants such as bittersweet and spindle trees. It can also be referenced as Appalachian Grass of Parnassus or Kidneyleafed Grass of Parnassus.
One species found in the Southern Appalachians is northern grass of Parnassus (Parnassia grandifolia). Another, more widespread species is Parnassia glauca, commonly known as fen grass of Parnassus.
The flowers are the real giveaway. Rising above the low-growing leaves on slender stalks, they have five white petals marked with delicate greenish veins. In the right light, the flowers almost look as though they have been carefully painted.
But there is more going on inside the flower than meets the eye.
A Plant of Wet Places
Grass of Parnassus has another characteristic that makes it especially interesting in the Smokies: where it grows.
Rather than thriving in dry, heavily shaded forest, it is commonly associated with moist or wet, open areas. In the Southern Appalachians, that can include seeps, wet meadows, streamside areas, and high-elevation openings.
These habitats are relatively uncommon compared with the vast forests covering the mountains. A small wet meadow surrounded by trees may look insignificant, but it can support an entirely different community of plants and animals.
One of the largest patches in the Southeast is found on Alum Cave Trail on Mt. LeConte. The ‘grassy slide’ section is located roughly 4 miles up Alum Cave Trail. This area is a steep mountain clearing of tall grass. From late July into September, Grass of Parnassus pokes through the grasses all along the hillside, competing to attract pollinators. Smaller patches can be found along all upper reaches of Mt. LeConte trails for those with a keen eye. Though Alum Cave Trail boasts the best viewing.
The Smokies are famous for their incredible plant diversity, and part of that diversity comes from the enormous variety of habitats found within a relatively small area. Changes in elevation, temperature, moisture, geology, and sunlight create countless growing conditions. A plant like Grass of Parnassus may be perfectly suited to one particular combination of those conditions.
A Sign of the Season
Grass of Parnassus typically blooms later in the growing season than many of the famous spring wildflowers of the Smokies.
While spring brings trilliums, orchids, trout lilies, and other spring ephemerals to the forest floor, late summer and fall bring an entirely different collection of plants into bloom.
Grass of Parnassus is part of that transition.
Its white flowers stand out against the greens and browns of late-season vegetation, particularly in high-elevation environments. Depending on the location and conditions, flowering can extend into the fall.
For hikers, this makes it one of those plants worth slowing down for. Instead of looking only for the bright colors of spring, take time to examine the wet openings and meadows later in the year. You may find a completely different world of flowers.
Why Wetlands Matter
The habitat where Grass of Parnassus grows is important for more than just wildflowers.
Wet areas in the mountains act as natural sponges. They collect and slowly release water, helping maintain streams and providing habitat for a variety of plants, insects, amphibians, and other wildlife.
Mountain seeps are particularly interesting. Water moving through the soil can emerge at the surface in small, scattered places, creating pockets of constantly damp ground. These tiny wetlands may be easy to walk past without noticing, but they can contain plants that aren’t found in the surrounding forest.
Because these habitats are limited and sensitive to disturbance, protecting them is an important part of preserving the Smokies’ biological diversity.
Look, But Leave It Growing
Like all wildflowers in the Great Smoky Mountains, Grass of Parnassus is best appreciated where it grows.
Picking flowers, digging plants, or trampling wet areas can damage the very habitat that allows these species to survive. Even a seemingly harmless shortcut through a meadow can crush small plants and disturb fragile soil.
Instead, stay on established trails when possible and take a moment to look closely.
The next time you encounter a small white flower growing beside a mountain seep or in a wet meadow, take a closer look. You may be looking at Grass of Parnassus; a rare wildflower that has found its place in one of the most diverse mountain ecosystems in North America.
*Wildflowers of the Smokies by Peter White, and articles from NPS.gov, NSCU Plant toolbox, and Smokieslife websites were used as reference information for this article*