You can find better pre-emergents at suppliers like John Deere/ Lesco (they've merged) than the home improvement stores. I agree with dchall, in my own findings granular pre-emergents don't perform as well as the liquid. The field testing that that the manufacturers site (so take that with a grain of salt) suggest that they perform about the same. If you're after grassy weeds, such as crabgrass, dimension is a great pre-em. If you're seeing a lot of both grassy and broadleaf, Prodiamine is a good alternative. The advantage with Prodiamine is that it is much cheaper to manufacture and has a number of generic versions. The 2-4D that Dchall mentioned is definitely a safe alternative in cool-season grasses for broadleaf weeds. Another, if you have trouble with crabgrass this season is Quinclorac. Quinclorac has the major advantage of being safe on Fescue even when it has just been seeded. To my knowledge it is the only herbicide that can boast that. If you mix it with a methylated seed oil, you have a good crabgrass control. The only odd exception is crabgrass that is in the intermediate stage, between newly emerged and mature quinclorac won't give any control during this period. As for the bright green grass, it isn't uncommon when you've been seeding so see color differences. Tiemco is correct about KBG being a dark green when it matures. There is a definite possibility that what you've seeded has come up much darker than what was there before. I ran across this today with a Fescue lawn that I seeded last Fall. The cheaper Fescue that was in the lawn looked much brighter than the cultivars that I used which included Speedway, Davinci and Blackwatch. So it's entirely possible, that the brighter colored grass was a lower quality Fescue, such as K31 that was there before. All the same, make sure that you don't over-do the seeding, which can lead to over-crowding and cause die-back or pythium blight in the up-coming months. Also, it's good to use a blend. There are a number of improved varieties of both bluegrass and fescue on the market today, which offer advantages over the older cultivars. For example, you can buy a mix of thermal blue, which is 10% bluegrass and the other 90% is made up of 3 different Fescue cultivars. It's highly drought tolerant and disease resistant. Either way, good luck and thanks for sharpening our skills with your question.

If it is something like Fescue -- mow as short as you can for your "Other" grass... and mow every week... Fescue doesn't like being scalped... especially not frequently... Now, if "Short" means 2" -- well... you may as well fertilize it and turn it green... or spot treat with round up... But.. if "Short" means 1" or less ... you probably have a good shot at keeping it under control. I found it took me a month now -- but the fescue clumps in my Bermuda are finally dying out from weekly mowings at 3/4"... They just can't take it. Thanks John

That looks like perennial rye grass to me, but I am not an expert. Maybe a lawn expert could confirm or deny it. Or, google it and see if it is what you have.

It is torpedograss. Torpedograss (correctly spelled as one word) - Panicum repens - is awful stuff. It is a Florida Category I invasive on the 2017 List of Invasive Plant Species. (Category I are the worst.) Very difficult to eradicate. Here's some info from the University of Florida: https://plants.ifas.ufl.edu/plant-directory/panicum-repens/ I hope you can get rid of it. Carol in Jacksonville