Let this be a caution to you, any time you add a new plant to your collection: you may want to keep it quarantined for a short bit until you make sure it’s completely pest-free.
I was checking some of the haworthia cuttings I acquired recently to see if there was any sign of progress on the rooting when I noticed white specs; the white specs were very similar to some that I had had on a cooperi truncata, which I had alternately been told was a result of guttation and mineral deposits from hard water, or excess calcium in the potting soil, etc. On one of my two cooperis, it’s been quite bad – even though I’ve tried treating it and removing it and repotting, etc.
The thing that jumped out at me here though was that this cutting hasn’t really been watered yet, so there was no reason for mineral deposits. I took some extra zoomed in pictures with my cell phone, checked my backlog of pictures back from the days since I acquired it (I took some when I got them, the day I potted them up, and then these recent ones) – and compared, and pretty much confirmed that both the new cuttings and the cooperi truncata are suffering from scale.
Scale is a pest infestation – sort of like succulent headlice. The little buggers don’t really crawl or move much, they latch onto a leaf and suck the juice out of it as the burrow in, and their hard shell covers and protects them. The common recommended treatment is a diluted rubbing alcohol mixture with a bit of dish soap, either applied with a q-tip or sprayed. In the case of the cooperi, the issue seemed so dense (and appeared to be down in the crevices between leaves) that I didn’t think a q-tip was going to cut it, so I did my best to evenly coat the leaves without soaking the soil too much.
Fortunately, it doesn’t look like it’s spread to other plants (which is a miracle, given how bad the cooperi truncata was) and it looks like after 2 rounds of spraying it down this past week it’s starting to clear up. The downside is that the damage won’t ever really “heal”; and the cooperi has several leaves that are either shrivelling and dying or likely will soon. Fingers crossed that the weakened plant then doesn’t succumb to rot or an infection. But I guess that’s why I have two of that particular plant.