any chance water could be dripping in the crowns of those specific plants (say, off the tree branches?)... crown damage from water and secondary rot or structural damage will cause Kalanchoe luciae to do that.

No idea but I'd definitely dig one up to try and figure out what's going on.

Someone recently (maybe Kara?) posted a picture she got from the internet with a spiral aloe that had gone flat. Maybe the poster remembers where that pic came from? And maybe the original site explains why it's flat?

Ya it was me:). The Aloe had rotted right down the middle. I will leave the link. I believe the owner of the Aloe thought it rotted because of the heat. I've read Spiral Aloes roots do not like their roots reaching temps above 80F. Little babies;). So they pretty much rot when too hot:(.

Maybe a gopher ate the roots;)?

Link:)

Well, I didn't learn a whole lot by digging. I decided to dig up one of the plants that was really close to another --

But it seems the roots are fused together. So they both came up. OTOH, the roots don't look bad.

I was looking for fungus and nematode root knots, but all I saw was a little yellowish peat (left from something in the distant past!) and a few pieces of perlite.

I saw no mealies or scale on any of the leaves, including those that I knocked off.

There's no apparent damage, but palmbob got me to thinking . . . I wonder if falling or damaged palm fronds have strafed the tops of the plants? We haven't had much rain, but we've had some wicked winds. I also need to check and see if a sprinkler head is hitting this area, although I would think all the plants in that area would show signs of too much water.

Hmm - very curious!

A succulent mystery! Looking at them up close you can really see how flat they are. What are you gonna do with it now:)?

I don't know! LOL I guess I can just plant the one(s) I dug up in a different spot and see how they do. I'll watch the others, I guess, to see if they all get back to normal. These are very resilient plants, so they should rebound. But I would really like to know what caused this.

That's what I would do. See if they go back to normal.

Maybe something covered it or fell on it. Looks like somebody sat on them:).

I have similar symptoms in Aloes, Agaves and other succulents that have had water dripping into their crowns.... plants just go flat all of a sudden (and often die soon after that, or at least loose most of the center foliage).

Palmbob - I think you may be on to something. This may be a dumb question, but do Christmas palms drip something that could be more "toxic" (for lack of better word) during a dry spell? That's what has been throwing me. We have been dry dry dry and these rotty looking symptoms appear. During the rainy summers, not so much.

I was looking more closely at other plants around my palms.

Aloe x spinosissima is showing signs of crown rot!

And a closer look -

Notice how the leaves look kind of funky in the first picture? It feels like edema.

I do have a couple of pups if this plant succumbs to rot. Shame if it does. This was the first year it finally bloomed.

And a couple of Aloe vera are showing spots of some sort.

I am not sure if there is a fungus or two at work on the Aloes and Kalanchoes. I am going to spray them with a copper sulfate solution. That worked the last time I had fungus starting.