If a tree is growing out of a top hat you need to inspect it to find out why and how this happened. You should probably investigate the area too. I mean, how could a tree grow out of a top hat anyway? Seems suspicious.
In the middle of your inspection you realize you need to saw (さ) the tree open to come to a good conclusion. This seems a bit unnecessary, but no! No! For the sake of this investigation you must saw the tree in half!
Currently there are no similar looking kanji which exist in the WaniKani learning system