There is dirt along the side of it, and it seems to have rotted some of the boards in the bottom left corner of the above picture.
1) Do I need to do anything about this? Presumably rot is bad... but what actually happens if I just leave it alone?
2) How would I go about replacing the impacted boards? Do I have to replace the whole thing? Or try to cut it and only replace the bottom piece?
3) Do I/how do I prevent the dirt from sitting right against the wood so that this doesn't happen again?