First, it is not pampas grass - that will not grow in your area (only hardy to zone 7) and is also evergreen. The seed heads showing on yours would lead me to believe it is some sort of Miscanthus, although these typically grow in clumps rather than what looks to be a mass planting of individual plants. There is a possibility it is false pampas grass, Erianthus ravennae, but this is a very tall growing grass (8-10') and I just don't get that sense of scale from your photos.

Regardless of the specific type, it is a deciduous grass and these need to be cut back annually. You can do so now if you wish to avoid the grass breaking off in winds or being crushed by heavy snows. However, many folks like the effect of the dried grass in winter and leave it in place, both for aesthetics and to feed birds. If you decide to leave it, in early spring, before any new growth begins, cut it back close to the ground - a couple of inches above soil level.

Ditto to all of the above.

Judging by its growth habit it is most likely Miscanthus 'Purpurascens'. Unlike most Miscanthus this one is not a clumping grass but a spreader. It is not an aggressive spreader but will spread outward in a tight and controlled way. You may need to shovel prune the edges every few years to keep it within its allotted space.

It is prized for its great fall colouring and its early bloom time among Miscanthus. We had a very hot and extremely dry year and so it did not get its normal screaming yellow/orange/burgundy tints.

I find it does not hold up as well to the ravages of heavy snow as well as clump forming Miscanthus but you could experiment and cut down half now and see what happens over the winter. I have been known to bounce the snow off them to give them a chance to provide winter interest.

Thanks for the replies.

I just Googled Miscanthus 'Purpurascens' and it does look a lot like that. I prefer to keep it during the winter as it does provide some privacy in our backyard, which is really nice. I am thinking I will try that and then plan on cutting it back in the early spring. My biggest concern is that wet/heavy snow would crush it and cause issues with it growing back but it doesn't sound like that would be the case.

You are right Brian, it is an extremely hardy grass that will start to put out new growth quite early in spring. Enjoy it. There is a forum that can answer any and all questions about your new plants, here is a link Name That Plant Forum