Euthamia graminifolia, perhaps. It's tough to see the flower detail in your pictures. Here is a link that might be useful:

It is a wildflower and it blooms in April, May and sometimes continuing into June if the weather is pleasant enough. That is when it blooms down here in southern OK---it may bloom a bit later the further north you go in OK. Indian paintbrush is an interesting flower that will grow okay on its own, but grows better in mixed plantings of other wildflowers and native prairie grasses where it can attach its roots to those of another plant. (It is not totally parisitic, so maybe hemi-parisitic would be the best description.) The ones in our wildflower meadows (which is just a nicer name for fallow farm land or old cow pastures) generally are blooming at the same time as Texas bluebonnet, blue star grass, the small white native asters, white-flowered yarrow, bluets, native phlox divaricata, and sometimes the pink spring beauties (which in some years finish up earlier than the other wildflowers I listed). I like the way the above flowers are blooming in patriotic shades of mostly red, white and blue with a little pink and purplish-blue in Spring. As we move closer to summer, more yellow-flowered wildflowers begin blooming alongside them. I'll link their LBJWC listing in case you want to read about their growing requirements and such. Indian Paintbrush Info from Lady Bird Johnson Wildflower Center

1. has already been identified as Datura stramonium. 2. is a Mallow of some description - it may be one of the wild flowers from your mix. (Not a Hollyhock) 3. Looks like very thickly sown Antirrhinums but there are lots of things which look similar at that stage. 4. is a mixture. There are Poppies, possibly Alyssum and possibly Cosmos. 5. is Chenopodium album. An edible weed. 6. & 7. Mixed Alyssum, Antirrhinums and other things I can't id at the moment. All the mixed seedlings need separating out and planting at greater spacing otherwise they will grow small and stunted and will not flower well, especially the Antirrhinums.

have had cornflower.. bachelor buttons for decades .. self sowing annual for me ... in the garden.. if you grow the blue long enough .. and have lots of plants .. the genetics will start to regress .. if thats the right term.. and you will end up with a few white.. pink .... and purple ones ... but you would have to have 100s of them to probably start seeing this ... ken