Glacier lily
A nodding yellow spring flower whose bulb is such important grizzly bear food that the bear's digging can grow bigger flowers the following year.
Glacier lily at a glance
Erythronium grandiflorum GLAY-sher LIL-ee; Erythronium grandiflorum is air-ih-THROH-nee-um gran-dih-FLOR-um
- Type
- Plant · wildflower
- Diet
- Producer
- Size
- Low and close to the ground: one nodding yellow flower on a bare stem that barely rises above the two long leaves beneath it.
- Conservation
- Not federally listed. Common within its range in mountain meadows and open forest at the parks listed above.
Eats sunlight, water, soil nutrients
Photosynthesizes through two long, smooth leaves at the base of the plant, and stores food underground in a bulb — the part grizzly bears dig for.
Is it safe to touch?
Harmless to look at and touch. The bulb underground isn't yours to dig up — that's a grizzly's job, and digging up any plant in a national park is against the rules besides.
Look for a patch of torn-up ground near a mountain meadow in early summer — turned earth, claw marks, the sod peeled back in strips — and you’re standing where a grizzly bear ate breakfast. It was after the bulb of the glacier lily, small and round and packed with the food a bear needs after a winter of sleeping. NPS calls that bulb a vital spring food, and a bear digs for it with the same long claws and heavy shoulders it uses for almost everything else.
Here’s the part that isn’t obvious from the mess: the digging helps the flower. NPS reports that grizzly digging releases nitrogen into the soil, and glacier lilies growing back in an old dig come up larger and more abundant in the years after. The bear that tears a meadow apart for lunch is, without meaning to, fertilizing next year’s crop of the same plant.
Glacier lilies don’t wait around once the ground thaws. NPS lists them among the flowers that announce spring at Yellowstone, blooming in May and June while patches of old snow are often still nearby. Find one nodding on its bare stem, yellow petals curled back and anthers hanging loose, and look at the ground around it. If it’s torn up and healed over, a bear has already been through, and the flower is doing better for it.
Did you know?
- NPS calls the glacier lily's bulb a "vital spring food" for grizzly bears at Yellowstone.
- At Glacier, grizzlies dig up lily bulbs with their claws and shoulder muscles, and NPS reports the digging releases nitrogen into the soil, growing larger, more abundant lilies in later years.
- Glacier lilies are among the flowers NPS lists as announcing spring at Yellowstone, blooming in May and June near the Lake area and Dunraven Pass.
Common questions
Why do grizzly bears dig up glacier lilies?
For the bulb underground, which NPS calls a vital spring food. Grizzlies use their long claws and strong shoulders to dig the bulbs out in early summer.
Does the digging hurt the flowers?
NPS reports the opposite over time: the digging releases nitrogen into the soil, and glacier lilies growing in old grizzly digs come back larger and more abundant in later years.
When do glacier lilies bloom?
Early. NPS lists them among the flowers that announce spring at Yellowstone, blooming in May and June near the Lake area and Dunraven Pass.
What color are glacier lily flowers?
Yellow, with petals that curl backward, nodding on a bare stem above two long leaves.