Calflora Great Places to view California Native Plants:
CNPS Chapter: Sacramento Valley -- covering the Sacramento, Yolo, Colusa, Sutter, Yuba and lower Placer County area.
Calflora Planting Guide: in Sacramento
Wild Plants in Sacramento County Native Plants, by lifeform Native Plants at the edge of their range non-Native Plants by Jepson Bioregion: Sacramento Valley Sierra Nevada Foothills
What Grows Here? -- a county level flora --