Bloomipedia
Bulbous woodland star (Lithophragma glabrum)
Photo: Mark Pollock via iNaturalist · CC BY 4.0 · resized

Flower profile

Bulbous woodland star

Lithophragma glabrum

Bulbous woodland star (Lithophragma glabrum) is a flowering plant in the Saxifragaceae family, native in the lower 48 states, blooming mostly March–May across the U.S.

Native to Idaho

Bulbous woodland star is a wildflower that USDA PLANTS lists as native in the lower 48 states.

10states where USDA records it
453ID sightings*
3,104U.S. sightings*

*iNaturalist research-grade observations, as of October 17, 2026.

On our lists for: Idaho

Quick look

Lithophragma glabrum is a slender perennial western North American mountain plant in the Saxifrage family (Saxifragaceae), known by the common names bulbous woodland star, bulbiferous prairie-star, smooth woodland star, and smooth rockstar.

  • It belongs to the Saxifragaceae family. iNaturalist
  • USDA PLANTS describes it as an herb (forb) with a perennial life cycle. USDA PLANTS
  • USDA PLANTS lists it as native in the lower 48 states and records it in 10 states. USDA PLANTS
  • NatureServe lists it as native to Idaho. NatureServe
  • iNaturalist has 453 research-grade sightings of it in Idaho, ranking #84 among the 143 flowers on our Idaho list. iNaturalist

When does it bloom?

Flowering records by month in Idaho (iNaturalist research-grade observations marked “Flowering”) (27 records)

Conservation status

Federal (U.S. ESA)
Not listed No U.S. Endangered Species Act listing in the USFWS ECOS database. USFWS ECOS
NatureServe global
G5 Secure worldwide. NatureServe
Idaho
No list Idaho has no state law listing endangered or threatened plants, so we show NatureServe's Idaho ranks instead. NatureServe: SNR, not yet ranked in Idaho.
Rare elsewhere
Other states where NatureServe ranks it rare or missing: SD (S1). (S1 critically imperiled, S2 imperiled, SH possibly extirpated, SX presumed extirpated.)

Checked October 17, 2026. Rankings and lists can change, so follow the links for the latest.

Can you eat it?

For peopleNot well documented

None of the sources we checked (NC State Extension (no page for this plant), USDA PLANTS) say whether it's edible or poisonous for people.

For petsNot well documented

It isn't on the ASPCA plant list.

🌿 Never eat a wild plant unless you're certain of its ID; this isn't medical advice. Worried about a person? Call Poison Control at 1-800-222-1222. Worried about a pet? Call your vet.

Where does it grow?

USDA PLANTS records bulbous woodland star in 10 states.

recorded by USDA PLANTS on our state lists not recorded

See the full list of states

California, Colorado, Idaho, Montana, Nevada, Oregon, South Dakota, Utah, Washington, Wyoming.

Idaho counties with USDA records: Ada, Adams, Bannock, Bear Lake, Bingham, Blaine, Boise, Bonneville, Camas, Canyon, Caribou, Cassia, Clark, Clearwater, Custer, Elmore, Franklin, Fremont, Gem, Gooding, Idaho, Kootenai, Latah, Lemhi, Lincoln, Madison, Nez Perce, Owyhee, Power, Shoshone, Twin Falls, Valley, Washington.

Names, range and relatives

Native status by region (USDA PLANTS): Canada: Native; Lower 48 states: Native.

Other scientific names (synonyms in USDA PLANTS): Lithophragma bulbiferum.

County records: USDA PLANTS lists it in 180 counties across 10 states; the most are in Idaho (33), California (26), Utah (25).

More from the Saxifragaceae family (12 on Bloomipedia; most observed first): Fringe cups, Virginia saxifrage, Creeping foamflower, Threeleaf foamflower, Twoleaf miterwort, Youth-on-age, Cliff saxifrage, Prairie alumroot.

More Idaho flowers

Great mullein (Verbascum thapsus)

Great mullein

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Introduced

🌼 Few flowering records in ID
Showy milkweed (Asclepias speciosa)

Showy milkweed

Asclepias speciosa

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🌼 Blooms in ID: June–July
Arrowleaf balsamroot (Balsamorhiza sagittata)

Arrowleaf balsamroot

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🌼 Blooms in ID: April–June

Sources