Hello,
Coyote Thistle - Eryngium petiolatum
Marsh Speedwell - Veronica scutellata
Plantain Leaved Buttercup - Ranunculus alismifolius - fruits/seeds
Scouler's popcornflower - Plagiobothrys scouleri
Smooth Tare - Vicia tetrasperma (non-native)
The other day I was walking in the nearby Village Green Park in an unmowed area and found some Field Peppergrass (Lepidium campestre) which isn't native but I don't remember seeing it before.
Don Boucher
NE Corvallis