Replacing a tree
I'm contemplating options as to when and how to go about replacing a crucial tree in my yard and would love to have some input.
Here's a link to pictures of the existing tree and its context.
I am in Oregon, Zone 8. I have a small area of lawn right behind our house with a tree in the center (centered because I designed the beds off of the tree). The tree is a wild cherry and has what seems to be a deep rotten spot at just above where the roots meet the soil (the rotten spot is maybe 1 1/2' wide). This in combination with several other factors (the tree is a bit spindly and doesn't give as dense a shade as I would like, it has tons of little cherries that cause birds to sit in the tree -- I got pooped on 3 times in one day sitting under it, and that the cherries drop and make a mess for weeks and weeks) all lead me to want to replace it, though I am very reluctant to loose the shade and sense of enclosure created by the tree.
So, my dilemma is if I should remove and then replace the tree with a more proper shade tree (I'll ask for suggestions on that separately) or if I should plant a replacement tree at south edge of the cherry's canopy and let that tree grow for a couple of years before removing the cherry.
I keep going back and forth as to what is best. I'm also considering getting landscapers in to bid on removing and replacing it with a tree that already has a bit of size, though this option is probably out of my price range.
I would really appreciate your thoughts on this.