No idea what is causing a couple problems...

In the summer of year 2, I've been experiencing a couple weird things...

One thing that's just happened is that one of my pine trees that I had nice and enclosed by paths just... chopped itself??? Leaving only a stump.

Another thing is is that I've been getting messages about weeds spreading, and yet I don't see anything actually spreading, only a couple plants rarely turning into a dead plant.

I'm really confused here, sometimes my stone paths are getting destroyed too, any help would be appreciated.