Why not?
depending on your location you may have one or even zero satellites at that location.
You can set up a motor for the other satellites and you can always integrate a fixed dish if needed
Depends on several things. Will the tree block the satellite(s) you want to get at your location? Can the tree be trimmed to allow line of site if it does? To see if a tree or other object may affect you, go to dishpointer.com, enter your location and zoom in to where your dish is located. Go through the list and click each of the satellites you want to get with your motor, look for trees/obstacles that fall along the green line for that sat which could block the signal. There is even a box to check that enables a height checking feature which tells you how high an obstacle needs to be to block view of a satellite. As Iceberg said, you may find it doesn't affect you and there are other options if it does. Good luck!
Just install polar-mounted dish and see whether reception is acceptable. If satellite you wish to have to be received not receivable- move your antenna till you get good reception. You did not tell how far is your tree and how big is that- too less information. Another option- what till October Sun-outage and observe do you have clear LOS to satellites.