Rorippa subumbellata

Last updated

Rorippa subumbellata
Rorippa subumbellata.jpg
Status TNC G1.svg
Critically Imperiled  (NatureServe) [1]
Scientific classification OOjs UI icon edit-ltr.svg
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Brassicales
Family: Brassicaceae
Genus: Rorippa
Species:
R. subumbellata
Binomial name
Rorippa subumbellata
Rollins

Rorippa subumbellata is a rare species of flowering plant in the family Brassicaceae known by the common names Lake Tahoe yellowcress [2] and Tahoe yellow cress. It is known only from the shores of Lake Tahoe, straddling the border between California and Nevada. There are an estimated fourteen populations of the plant still in existence. [3] It grows only on the direct shoreline of the lake, occupying a seven-foot semi-aquatic zone between the high- and low-tide marks. [3] It is directly impacted by recreational activities on the lake, enduring bombardment by boat wakes, trampling, and construction of docks and other structures. [3]

Contents

The population sizes change with the lake's water level, with populations growing largest as water levels drop, exposing more sand habitat. [4] High water levels may be beneficial at times, however, since they kill off competing plant species growing on the beaches. [3] Restoration of this species has been hampered by low seed germination, but recent research has reduced this problem. [5]

Description

This perennial herb produces spreading, branching, hairy stems up to 20 centimeters long. The leaves are 1 to 3 centimeters long, oblong or lance-shaped, and wavy along the edges or divided into lobes. The inflorescence is a compact raceme of mustardlike flowers with yellow petals each about 3 millimeters long. The fruit is a hairless silique a few millimeters wide containing tiny seeds.

Conservation

Rorippa subumbellata is listed as a critically endangered and fully protected species by the State of Nevada and is a California endangered plant species. [6] [7] [8] It was removed as a Candidate species for federal listing in 2015 following successful conservation efforts guided by regional adoption of the Tahoe Yellow Cress Conservation Strategy. [9] [10]

References

  1. "NatureServe Explorer". NatureServe Explorer Rorippa subumbellata. NatureServe. 2022. Retrieved 22 May 2022.
  2. NRCS. "Rorippa subumbellata". PLANTS Database. United States Department of Agriculture (USDA). Retrieved 23 October 2015.
  3. 1 2 3 4 Center for Plant Conservation
  4. The Nature Conservancy
  5. Ingolia, Mia; T.P. Young; E.G. Sutter (2008). "Germination ecology of Rorippa subumbellata (Tahoe yellow cress), an endangered, endemic species of Lake Tahoe". Seed Science and Technology. 36 (3): 621–632. doi:10.15258/sst.2008.36.3.12.
  6. Nevada Division of Natural Heritage (April 2025). "NDNH Current Track List" (PDF). heritage.nv.gov. Archived from the original on 2025-10-01. Retrieved 2025-10-24.
  7. "NAC: Chapter 527 - Protection and Preservation of Timered Lands, Trees and Flora". www.leg.state.nv.us. Retrieved 2025-10-24.
  8. "Tahoe Yellow Cress". wildlife.ca.gov. Archived from the original on 2025-08-29. Retrieved 2025-10-24.
  9. "12-Month Findings on Petitions To List 19 Species as Endangered or Threatened Species: Notice of 12-month petition findings". www.fws.gov. 2015-10-08. Retrieved 2025-10-24.
  10. Nevada Department of Conservation and Natural Resources (2025-10-17). "Annual Survey Provides Key Insights into Status of Tahoe Yellow Cress". dcnr.nv.gov. Retrieved 2025-10-24.