Indicator
Tahoe Yellow Cress (Rorippa Subumbellata)
Basics
Tahoe Yellow Cress (Rorippa Subumbellata)
Tahoe Yellow Cress
Action
Program
Each Unit (number)
VP21: Maintain a minimum of 26 Rorippa subumbellata population sites.
The number of population sites that are maintained as suitable habitat for sensitive plant species (as determined by a qualified expert).
This Indicator is reported in the following LT Info areas:
Accomplishments

Number of sites occupied by Tahoe yellow cress during the survey period from 1979 to 2019. The number of occupied sites is highly correlated to the lake level, where high lake levels result in fewer occupied sites.

Name Options
Tahoe Yellow Cress - Rorippa Subumbellata
General

Program Tahoe Yellow Cress Monitoring

Approach

Knowledge of TYC distribution has been developed through shorezone surveys since 1979. Before 2000, surveys followed a general protocol and were completed at various times during the summer. Since 2001, surveys are conducted the first week of September following a standardized protocol. During the first survey in 1979, 32 TYC sites were surveyed; this has since grown to 55 sites. A survey “site” is defined as a stretch of public beach, adjacent private parcels, or adjacent parcels under a combination of private and public ownership. Surveys include stem count estimates as a measure of TYC abundance because clonal growth makes it impossible to distinguish individuals. The amount of available shorezone habitat for TYC fluctuates widely with changes in lake level, with high lake levels leaving little habitat. On average, over 70% of surveyed sites are occupied when the lake is below 6,225 ft. in September, but less than 40% are occupied when the lake level is above 6,228 ft.

To download all of the Tahoe yellow cress data on this page please see Tahoe Open Data.

Partners

Associated Programs data not provided.