Help identifying these Minnesota wild plants

I've done quite a bit of investigation, but I'm at a loss for a few of these plants on my property.  I've been working on my foraging skills over the last few years.  I'm getting better, but it's always nice to get others opinions/thoughts.

sweet little yellow "button" flowers



Oxe Daisy.. I think??



Yellow Clover??


??



Looks like it's growing by some "Salsify"

The first photo looks like Tansy, third is Golden Rod, fourth looks like Birdsfoot trefoil. Not sure about the others. Hope that helps!

Blackbird... thanks much.. yep.. that is Tansy, and looks to be BirdsFood Trefoil.

Thanks Much!

#3 looks like some kind of Goldenrod.

Hello again!  Tansy, aster, goldenrod, birdsfoot trefoil, and pearly everlasting.  Tansy is an exotic, naturalized throughout the area.  It has medicinal uses and probably was deliberately imported from Europe.  There are several asters and goldenrods, all lovely wildflowers.  I often include them in bouquets with my cultivated flowers.  Bird's-foot trefoil is also an introduced plant, often grown as a fodder crop.  Pearly everlasting is one of my childhood favorites.  You can dry it and include it in dried arrangements, or you can make a very nice tea. I've included a link that is useful.  You'll have fun with it.  Watch for fact sheets (not all entries have them) that will fill you in on uses of a plant.  You'll want to explore the links too.  Whenever I am considering adding something new to my collections, I check out the noxious plants list to make sure I'm not getting in over my head.   

http://plants.usda.gov/java/

I forgot to add this to this forum... I got this great book that list's the plants used by the Great Lakes Ojibwa.  It's called "Plants Used By The Great Lakes Ojibwa".  It's a huuuuuge book w/ the line drawings of the plants.. followed by what type of topography, and all of the uses the Ojibway had for them.  Super cool book for only $20.  Here's the link http://glifwc.org/publications/index.html

Thanks for the identification BreadGal