Assessing the status of Lupinus lepidus var. cusickii in Denny Flat, Baker County, Oregon
The purpose of this project is to document all extant populations of L. lepidus var. cusickii on BLM managed land and develop restoration protocols. In 2010, our activities focused on
The purpose of this project is to document all extant populations of L. lepidus var. cusickii on BLM managed land and develop restoration protocols. In 2010, our activities focused on determining the distribution of L. lepidus var. cusickii populations in the Denny Flat region of Baker County, estimating the size of populations, and determining potential threats to these populations. This information will provide the BLM with important information to assess management plans for the conservation of this sensitive species.
During the 2010 field season, approximately 3900 acres in the Denny Flat area of Baker County were surveyed for L. lepidus var. cusickii. Five populations were observed. Four of the observed populations appeared to be larger than previously documented. Although this may be due to increased population size, it is more likely that this stems from using different methodology and technology to survey and document the populations. Lupinus lepidus var. cusickii was somewhat uncommon throughout the entire area, but when encountered, formed dense populations. Although there was a noticeable amount of dead reproductive adults, this was counterbalanced by a high rate of recruitment. No solid set of habitat characteristics, aside from the presence of tuffaceous soil, could be developed throughout these surveys. Lupinus lepidus var. cusickii was most commonly associated with open spaces with very low competition on highly erodible tuffaceous soil. The plant community was dominated by desert shrubs. Disturbances and potential threats were observed at each occurrence and were mainly limited to invasive species and potential human disturbance.
In the 2011 and 2012 field seasons, additional surveys will be conducted in eastern Oregon. Areas of interest have been identified by the presence of tuffaceous soil, the main habitat indicator of Lupinus lepidus var. cusickii. These surveys will provide accurate information about the true extent of this species’ range and aid in the prioritization of management actions.