GamePlayer No. 1058 wrote:

..........4. My grass seems to be reseeding itself in certan areas, that is to say,
that there is plenty of areas that look like they are reseeding themselves
evident by the grass seeds that are at the tips of my lawns blades. It
seems that even though I cut on the highest setting on my rider mower, the
grass still wants to reseed,...........

If you have seed heads at normal mowing height then it sounds like you
have poa annua (annual bluegrass). This is one of the few grasses that
forms seed heads at such low heights. It looks fine in cool weather,
but it will brown out severely in hot weather. Not good.