Threebract onion

Imperiled  (NatureServe)[1]
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Monocots
Order: Asparagales
Family: Amaryllidaceae
Subfamily: Allioideae
Genus: Allium
A. tribracteatum
Binomial name
Allium tribracteatum
  • Allium tolmiei Baker ex J.M.Coult. 1885, illegitimate homonym not Baker 1876

Allium tribracteatum, known by the common name Threebract onion,[3] is a species of wild onion[4] found in California.

Distribution and habitat

The plant is endemic to California, where it is known only from the slopes of the Sierra Nevada in Tuolumne and Calaveras Counties.[4][5][6]


Allium tribracteatum is a small onion plant producing a stem only a few centimeters long from an oval-shaped bulb. There are two leaves which are usually much longer than the stem. The inflorescence contains up to 30 petite white to purple flowers, each less than a centimeter long. Tepals are white to pink with red or purple midveins; anthers purple; pollen gray.[4][7][5] Flowers bloom March to May.[5]


  1. ^ "NatureServe Explorer 2.0".
  2. ^ Kew World Checklist of Selected Plant Families
  3. ^ CalFlora taxon report 237, Allium tribracteatum Torrey (three bracted onion, threebract onion)
  4. ^ a b c Jepson Treament, University of California, Berkeley . accessed 3.20.2013
  5. ^ a b c Flora of North America v 26 p 269, Allium tribracteatum
  6. ^ United States department of Agriculture Plants Profile, Allium tribracteatum
  7. ^ Torrey, John. 1857. Reports of explorations and surveys : to ascertain the most practicable and economical route for a railroad from the Mississippi River to the Pacific Ocean, made under the direction of the Secretary of War 4(5): 148.