Clematis ligusticifolia (Western
Clematis, Virgin's Bower)
This fine climbing vine grows vigorously to 40,' although it is significantly shorter in its northernmost ranges.
Delicate clusters of showy white flowers bloom from June to mid-August and are followed by equally decorative fluffy seed heads.
Hardy between USDA zones 5-10, Western Clematis grows on dry, weak soils from BC through the eastern ranges of the Cascades.
Game birds favor this plant.
Photo below left courtesy of PD-USGOV-USDA.