Do You Know What Plant/weed This Is?

Quaking Aspen seeds?

Some variety of milkweed maybe.

Looks like milkweed especially being in Sacramento. I hope it is because that is what the Monarch butterfly depends on and it is being wiped out by pesticides. If this on the American River Parkway it is a wonderfully preserved long strip along the river. I have spent hours walking and biking it myself when I lived in Sacramento.

I don't know, the milkweed I am used to from north of Dallas area where I grew up, always had a thicker stem and different heads. http://www.glorious-butterfly.com/butterfly-garden-plants.html . I would almost bet it is related to a foxtail. Maybe a Short-Awned Foxtail, Alopecurus aequalis? http://www.illinoiswildflowers.info/grasses/plants/sa_foxtail.html

Thank you everyone for your input!

Dan, I don't think it's foxtail. I saw a lot of foxtail around but it didn't look like this.

Jim, it was the American River it was by.

It could very well be a milkweed. There was a lot of it! I will investigate more