It looks like it could be wheat. If you look up "wheat leaf blade" on google images, there are some pictures that look like that. I am most certain though that grass is not one of those from the mix. Most of those have flat blades. I hope this helps!

I seeded last year with some Pennington tall fescue. Turns out a lot of that was orchard grass. This looks like the young orchardgrass looked for me last year.

Thanks for the responses. I really hope it's wheat, but maybe I should try to start pulling it in case it is orchard grass :/ I suppose orchard grass could be counted in the "other crop" section of the seed breakdown. Bummer.

Yes it could, and so could wheat. I don't have any experience with handling wheat. If it's orchardgrass, it should be easy to take care; it grows faster than even KY-31, so in between mowings it should be easy to identify if it's mixed in anywhere else in your lawn. I've tried pulling it up.

Sometimes they come right out when you pull. If you don't get it all, it will grow back soon --- it's hardy grazing stuff. If you can get it up while it's young, do it.

Otherwise it can outperform your turf grass. It just keeps growing and growing, and it's tillers get larger and larger in size. Regular mowing just seems to push it down, where it kind of grows prostrate. I've had a helluva time this fall with overseeding because of orchardgrass. Thankfully, it doesn't spread except by seed.

Would suck for a grass seed blend touted as slow and low growing to include something like orchard grass (most likely part of the "other crop" I suppose). *sigh* guess I know what I'll be doing this weekend.

I would not automatically lay blame on the seed. You brought in new topsoil, which can have weed seeds in it, and you brought in straw, which can have weed seeds in it. And then you did not pre water it to bring up any weeds so you could kill them with a weed killer. So had you not done all those things, you would have/should have gotten better results.

I actually was blaming the straw first off, and hoping that it was wheat which should die off after a season. If it's orchard grass, I just don't think it would be considered a "weed" and that's why I said if it came from the seed it was probably part of what is listed as "other crop". I guess it could have come from the topsoil that was brought in too. I wasn't "automatically laying blame" to the seed - just saying it would suck if the seed contributed to the problem (it does have an "other crop" and a "weed seed" section on the content label).

Regardless of how it got there, it sounds like it needs to be removed now, while it's young, in case it is a perennial.