Need more information. Do you plan to light the branches or just the trunk?
If it is to light the trunk, this could be a fairly easy solution but you would still need to run the 110V line 400 feet which I will leave to others. You can use waterproof RGB strip lights that come with a controller and power supply. No learning curve required. The one I used for Christmas lights on the house is often called "dream lights" and have the designation IC 6803 which designates the IC built into the strip. They come in packages with the waterproof light strip, controller, remote, and power supply. You would need a waterproof box for the power supply and controller. The rest can be exposed to the elements. These have some very nice programs built into the controller. You can also choose just one color. The length of a strip is 15 M or 16.7 feet. It's obvious that you would need more than one strip for a tree. One controller will work two strips. If you go beyond two strips it makes sense to run them from one larger power supply and have 2 or more controllers. I just looked up a 240W power supply which would power eight 5M strips and it is only $24 postpaid. In that case you should not include a power supply with the strip order.
For a description look at this listing on eBay: https://www.ebay.com/itm/Magic-Dream-Color-5M-6803-5050-Led-Strip-Fairy-Lights-133-Effects-RF-Remote-Lamp/262063598092?hash=item3d04352a0c:m:mxeBvOSYJq7H-sV3lGitPUw