Lupinus oreganus on the BLM Roseburg District: population monitoring and restoration
This document reports preliminary findings and summarizes methods used in monitoring the threatened species Lupinus oreganus on the BLM Roseburg District. In 2013, the eleventh year of the project, we
This document reports preliminary findings and summarizes methods used in monitoring the threatened species Lupinus oreganus on the BLM Roseburg District. In 2013, the eleventh year of the project, we monitored L. oreganus populations by assessing foliar (leaf) cover (a measure of abundance) and counting racemes, and numbers of fruits produced at a total of six sites on the Roseburg District. Data collected this year are from the ninth year of monitoring at Dickerson Heights and Stout’s Creek, the tenth year of monitoring at China Ditch, and the eleventh year of monitoring at Loose Laces, Letitia Creek, and Callahan Meadows.
- From 2012 to 2013, foliar cover increased at China Ditch, Loose Laces and Stout’s Creek sub-popualtion 2. Foliar cover of lupine decreased at Stout’s Creek sub-population 1and Callahan Meadows, while remaining relatively stable at Dickerson Heights. (Letitia Creek was not monitored in 2013 due to the presence of a squatter camp in the vicinity.
- The number of racemes from 2012 -2013, increased at two sites (Loose Laces and Stout’s Creek Sub-population 2) and decreased at Callahan Meadows, China Ditch, Dickerson Heights, Letitia Creek and Stout’s Creek Sub-population 1.
- At Letitia Creek, both foliar cover and raceme count have declined precipitously since monitoring began in 2003. Since 2006 cover has steadily declined from more than 8m2 of foliar cover to just more than 1m2 in 2011. In 2012 foliar cover increased slightly to 1.5m2, however only 2 inflorescences were present at the site and no fruits were formed on either raceme. The site was not monitored in 2013 due to the presence of a squatter camp in the vicinity.
- The number of fruits/raceme in 2013 ranged from 2.9 – 6.0 (Stout’s Creek and Loose Laces respectively). No viable fruits have ever been found at Callahan Meadows.
- In 2012 and 2013, meadow knapweed (Centaurea pratensis) was found along the roadside at China Ditch near the end of the Patch C Roadside transect. All flowering individuals were removed by IAE staff, however it is recommended that the area continue to be monitored for the noxious weed which could quickly invade the surrounding lupine population.