We have had this Ponytail Palm for at least 10 years and it has always been healthy. We re-potted it about 6 months ago and even that didn't seen to cause distress. But in the last 3 days, the tops of it are falling out. The base of the leaves that are in distress are moist, yellowish to white, and some smell rotten. One stem that is now missing a top is firm and dry, the other is wet and mushy. The only thing I can think of that has changed is that I did have a wasp nest show up in it and I sprayed it with wasp killer about 10 days ago. I don't know if that would have hurt the plant. I'm desperate to find an answer. We love this plant that we have named Lolita. We live in North Florida, if that makes a difference on any advise you could provide.