Narrow-leaved milkweed

"Narrow-leaved milkweed is the
most widespread species in California, growing in
every region of the state except the Sonoran Desert
and the upper montane, subalpine, and alpine
zones of the Sierra Nevada. Suitable locations
include dry to moist soil in open, sunny areas. It is typically found in plant
communities such as valley grasslands, wetland-riparian areas, foothill
woodlands, and chaparral, and clearings within yellow pine, red fir, and
lodgepole pine forests."