I did it on the cheap and the guys did a messy job of removing limbs, so there are stubs in places that I am not happy with. But I'm very glad I did it as many plants in my backyard are happier and fuller now. It hasn't hurt a single one of the trees (although I don't have any pines).

I do suggest you have a real tree company do the work and keep an eye on it so that the limb removal is neater than mine was.

I too have limbed up my pines, maples, oaks and spruce. I also limb up my flowering trees so I can grow shrubs under them. It seems that if the large maples are crowding the large pines they must be planted close together. How about removing one of each?

It's not all about what's going on above ground - what about root competition?? There are parts of my yard where I grow in containers because the nearby tree roots are sucking all the moisture and nourishment out of the soil.

Have a tree pro do it. It can get expensive but they have the specialized equipment and the experience to do it correctly and SAFELY. You don't want a chainsaw injury or a fall from that kind of height. This is where I get to say "Trust me, I'm a doctor!" Make sure that the service doesn't "top" trees and that they are bonded. That being said get those trees limbed up!
I can't comment on how pines tolerate it as I have no pines but limbing up my over grown maples and black locusts made a huge differance in the "live-ability" of my yard. Light and air now get in, grass will grow, My plantings are doing much better and I have far fewer mosquitos which since this is a West Nile Virus zone is a very good thing.

I finally took down my walnuts altogether. I liked them. My husband did not. He is right that they are messy trees and were poisoning everything else around them. Since your mulberry is male you don't have that mess but they are brittle trees as they age, not as bad as a sycamore but that's not saying much. Ultimately, you have to go with your gut feeling about which trees go, if any, and which trees get trimmed. You may want to do it in stages, one this year, one next year that kind of thing. Sorry for being long-winded but I think you'll be pleased if you get the trees trimmed.

I appreciate the input.

The first tree to go will probably be the smaller of the two walnuts, which had a bark injury from sun hitting the trunk in winter when it was quite young, and has always been retarded in growth. I planted two in order to assure pollination; I know the squirrels like this, but of course we have never once gotten a mature walnut from either tree, as the squirrels like them so well.

The second to go will undoubtedly be the pine to the west side of our house. It has grown frighteningly tall, and is too close to the house for comfort. Limbing it up further would make a bare trunk fall on the roof if it ever fell. Another consideration, though, is an oak tree owned by a neighbor which is just beyond, between the sidewalk and the street. It has several dead branches. After a similar oak fell down in another part of our neighborhood, a friend told me that when the developments around here were built, a great many pin oaks were planted. Apparently this is not a good area for them, and as they age their roots tend to rot, and they fall. The prevailing wind would tend to make it fall toward our house. I sometimes think it might be better to have a pine in place to block the pin oak if that ever happens; they are a very heavy tree.

I think I will definitely work toward getting a qualified tree surgeon to at least limb up many of the trees, and proceed further with his or her recommendations.