I live in northeastern Minnesota. We installed a new lawn at the end of June.

First we had a guy come in and regrade the back yard (it was a terrible mess) and he hauled out a lot of dirt then spread new dirt for us. He said it was a mixture of loam, black dirt, and manure. The manure didn't look like fresh manure, it looked like a pile of rich dirt, which I took to mean it was composted. After he left we smoothed it out, used a broadcast spreader to put down milorganite and Scotts bluegrass mix, water rolled, and put a thin layer of straw down.

There was a section of the front yard we had done at the same time, but we were working on another project in the area and decided to put grass seed down after we were done. We put that seed down about 3 weeks later using the same process.

I tried to water consistently, though I did miss here and there and don't think I watered deep enough. I've done a much better job the last couple of weeks and have watered deeper as well.

The weeds started popping up first, but I figured the grass would come in and we'd be able to deal with the weeds next spring. But, the weeds got thicker and thicker and I'm worried they will choke out the grass. The smaller section we did last has fared better. There are some weeds, one area area (about 5'x5') is like the back yard, but it's in better condition overall. We did a mixture of Scott's KBG and some perennial ryegrass. We wanted to do the ryegrass in the back because we read it plus the bluegrass was a good mixture for up here and it germinates quicker.

We are planning to renovate the front lawn this fall. It has some minor grading and is quite weedy. Our plan was to aerate the lawn, topdress some uneven areas, and apply a generous overseeding of bluegrass with some perennial ryegrass. While doing all that we were also going to overseed the backyard with the KBG and ryegrass.

Should we consider an herbicide to aid us with this mess? We had hoped that with proper mowing/watering/fertilizing we'd be able to have a decent yard without the use of synthetic chemicals. However, with all these weeds we are wondering if we shouldn't apply a nonselective herbicide and try again. If we go that route would we need to act fast in order for it to do its job and have the ground safe for seeding? Or should we apply a post-emergent pesticide and risk it hurting the grass? Or wait until spring to apply a pre-emergent?

We live in a small town quite a distance from a bigger city and most places scoff at the idea of coming here. So, we're trying to take care of this ourselves. Do we need a professional for some help? We live in a neighborhood with nice yards, though we aren't seeking perfection. We aren't worried about a weed or two, just would like more grass than weeds.

Here is an album of photos I took just before watering this afternoon.

http://imgur.com/a/Ji3DI