u/chadwick293

Just bought house last winter....the grass started out super green and now these have popped up making it look like grass is brown and dead in patches. Haven't done anything but water and cut, really want to make it look nice though and want to learn more about lawn care. Last Pic is of backyard which looks like the feo t yard did before these popped up. Can anybody identify what these are and how to get rid of them? Or better yet any kind of lawn care advice to have a nice looking yard? Location is near DFW area, Texas. TIA!