Ambrosia eriocentra

Summary

Ambrosia eriocentra is a North American species of ragweed known by the common names woolly bursage and woollyfruit burr ragweed.[4]

Woolly bursage
Woolly bursage on a portion of periodically exposed, dry river bed
(Red Rock Canyon in the Spring Mountains of southern Nevada, elevation about 1300 m).
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Asterids
Order: Asterales
Family: Asteraceae
Genus: Ambrosia
Species:
A. eriocentra
Binomial name
Ambrosia eriocentra
(A.Gray) W.W.Payne[1][2]
Synonyms[3]
  • Franseria eriocentra A.Gray
  • Gaertneria eriocentra (A.Gray) Kuntze

Distribution edit

The plant is native to the Mojave Desert in the southwestern United States, within southern California, southern Nevada, northwestern Arizona, and southwestern Utah.[4]

It grows in the Mojave's plains and mountain ridges up to 1,700 metres (5,600 ft) in elevation.[1][5]

Description edit

Ambrosia eriocentra is a rounded shrub reaching over 1.5 metres (4.9 ft) in height. The stems are brownish gray in color, with young twigs coated in light woolly fibers and older branches bare. Leaves are lance-shaped and up to 9 centimeters long, not counting the winged petioles. The leaves have rolled lobed or toothed edges.[1]

As in other ragweeds, the inflorescence has a few staminate (male) flower heads next to several single-flowered pistillate heads. The bloom period is April to June.[1]

The fruit is a green burr with long, silky white hairs and several hair-tufted sharp spines. The burr is around a centimeter long.[1][6][7]

References edit

  1. ^ a b c d e Jepson eFlora: Ambrosia eriocentra
  2. ^ In: Journal of the Arnold Arboretum 45(4): 423. 1964. "Name - Ambrosia eriocentra (A.Gray) W.W.Payne". Tropicos. Saint Louis, Missouri: Missouri Botanical Garden. Retrieved March 25, 2010. Basionym: Franseria eriocentra A.Gray; Published in The Proceedings of the American Academy of Arts and Sciences 7(2): 355. 1868.
  3. ^ The Plant List Ambrosia eriocentra (A.Gray) W.W.Payne
  4. ^ a b Calflora taxon report, University of California, Ambrosia eriocentra (A. Gray) Payne woolly bur sage, wooly bursage
  5. ^ Biota of North America Program 2013 county distribution map
  6. ^ Flora of North America, Vol. 21 Page 13 Ambrosia eriocentra (A. Gray) W. W. Payne, J. Arnold Arbor. 45: 423. 1964.
  7. ^ Payne, Willard William 1964. Journal of the Arnold Arboretum 45(4): 423-424

External links edit

  • Calflora Database: Ambrosia eriocentra (Woolly bur sage, Wooly bursage)
  • Jepson Manual eFlora (TJM2) treatment of Ambrosia eriocentra
  • UC Photos gallery: Ambrosia eriocentra