Can you describe the situation better? Are the trees in question in a wooded area or more in the open? Are they young trees, pole size trees, or even larger? Is the area in need of browse or ground level cover?
Assuming you have them(since your location is not listed), ask yourself..."Do I like grouse?" I you like having ruffed grouse around your property, keep those aspen stands as long as they are not totally messing with your mast trees. The buds in the upper branches are prime winter food for ruffed grouse throughout their range. That's not to say they don't have other benefits and aren't used by other critters, but grouse is my primary reason for keeping them.
The aspen also increase the size of their grove with each clear cut provided there is room for them to expand. The cut trees provide a food source for the grouse and deer after they are cut down.
AS NT stated, there is a lot of information out there for improving aspen for grouse habitat. The pamphlet he mentioned I have seen before and should be somewhere on the MN DNR website. There are also resources on the WI DNR website(as well as other states wildlife agency sites) and The Ruffed Grouse Society has some great resources and links as well. My advice would be to research as much as you can and then get a "plan" in your head that suits your needs and wants as far as deer, grouse, and any other critters on your land are concerned before I started just randomly cutting the aspen. Mixed age stands, as mentioned previously are the best option, how you get that on your place will need some thought and knowledge. Good Luck!So if i fell a few of them, it will help the grouse?
Wildthing, I observed similar results when I did my clear cuts of aspen groves in the winter. My trees had reached the age and height where a winter clear cut of them was the best management option. I did not get to the second batch of clear cuts this winter, which is okay by me. By staggering the cuts, it will give me a slightly different age structure of my groves when I do cut them this winter.
My aspen areas are not huge, some being only 1/4 to 1/2 acre in size. I do consider myself lucky to have them at all on my land as it is mostly an oak/cherry mix of hardwoods other than the pines I have planted. This is my second go round on clear cuts of aspens with the last one being about 25 years ago.
I have sat in a young poplar stand watching a herd of deer munch leaves instead of walking out into a beautiful alfalfa field ... think of them as a food plot