Could be rye grass, which is used to oversees bermuda when it goes dormant.

It's certainly in the mint family, which would explain its aggressive behavior. My first thought was lemon balm, too. A delightful culinary herb but a problem in the garden if not carefully monitored. Normal, routine care of our lawns and gardens will always include a little handwork. Especially when it comes to keeping the weeds under control. Hand weeding is still the most efficient method for some weeds. Pull off a couple of leaves, crush them between your fingers and smell the scent. Lemon balm is decidedly lemony.

Ed......they're still kicking. In the 2nd pick, it's raining. Water makes them scatter. I posted in the Garden Clinic...per Julias suggestion. I'm told they're pollen beetles. They don't seem to be causing any damage to the foliage....just really ugly! I can dump them out of the flower blossoms and throw them away....seems to be the most organic means to their "end".

It seems to get still greener as it gets closer to the green cap just to the right of the yellow area (1st picture). Do you know what that green cap goes to? Could there be a low spot where it's greener? The tall grass circles in the last picture is "just" a grassy weed. I'm not up on northern lawn herbicides, so I'll let someone else help with that. You should not have to treat for grubs annually. Grubs are typically a problem in July and August, if they are going to be a problem. If you suspect you might have grubs, dig up one square foot of turf and inspect. If you see fewer than a dozen grubs, place the turf back and leave it alone. That is normal. If you have an uncountable mass of grubs, then you need to treat. But in a normal 10- year period you might have grubs once. Besides insecticides are really not good for the rest of the insects and microbes living in the soil. How are you watering? You seem to have done some reading on this forum, so you've probably read my thoughts on deep and infrequent watering.