Is it a type of evening Primrose?

Yup, it's definitely one of the evening primroses, genus Oenothera. There are tons of different species, hybrids, and cultivars, so that's as specific as I'll try to get. Many of the native types are the tall growing yellow flowering type (though not all of course). It's a really nice one though.

Showy evening primrose (Oenothera glazioviana). Very common, frequently asked about.

There are none native with certainty to Seattle. O. biennis (rare here) is Eurasion but may also be widespread North American species depending on which author you follow. Common O. x glazioviana is a garden hybrid gone wild. O. villosa var. strigosa is native to the West but uncommon in Seattle and probably not native here.

Good information. So the ones I see on roadsides are basically naturalized rather than native. I really like them.

Take care,
Grant

Mostly I see the common largeflower hybrid but not always, in recent years I have been seeing quite a few that are one of the others (likely O. biennis). Their flowers are noticeably smaller.

Where could this have come from. I have never had them until this year. Wondering if one of my mischievous garden friends may have thrown the seeds?

ERIC

Very common so it could have come in by various means. We had a nice bunch of opium poppies on the mound at the Camano place this year. Last year I noticed them growing along the road that goes by. This year we had them on the mound, perhaps hundreds of feet from the nearest ones on the road.

Not absolutely certain one of us (not me, anyway) didn't throw some opium poppy seeds onto the mound, but they didn't come up in just the one spot.

Seeds travel, that is part of their purpose.

Does any one know if this makes seed that any PNW birds love? If it did Id leave it after the flowers stop. One thing I like about these, as well as mullian, fox glove and my old , night scented nicotiana, is the way they just come up, often in a spot that could use a little fill in for the season while something else is growing into the spot. That suprise plant that you see on "the Walk".I have not noticed this to be at all pushy or invasive (Yet).Last year I was thrilled to see a little woodpecker going up and down a dry mullian seed stalk, fending off the ocasional smaller bird with out letting go. Watched him for a week or so, He was black and white with red trim, seemed to be between a Robin and a Towhee in size. Love to see more of these.

Probably a downy woodpecker. Hairy woodpecker has same general appearance but is larger. If you look these two up you can get their dimensions and decide which one it was.