yucca-plant

So, my family has some yucca plants in our backyard (I think soaptree yuccas? The image above is just one that I got off of google) and I was pulling dead leaves of of one of them and the whole thing came falling down. I looked at the stump and it was like, black and soft and there was this white mushy stuff on it. Does anybody know what’s wrong?

Update: I’ve figured out the problem. It was just a matter of one of the stumps being rotten, and the white stuff was just dried tree sap.