I'm no sunflower expert but I researched it a bit on the web and there are over 50 species all native to North America. I couldn't find anything with good pics, but all the ones in your photos look like sunflowers if that is what you are asking. You might try Wikipedia for some more info.
Hi aebanda, I'm with everyone else, dont really understand if you just want to show the lovely picture or are you wanting to know how to grow sunflowers, where to buy the seeds or if these are true sunflowers, can you get back to us and tell us what info you are after, I'd hate you to think we were all ignoring you in any way, so can you clarify what kind of information you are seeking. Good luck, WeeNel.