Oh Nexians! So glad to see things are still awesome here. Our cacti subforum has grown in my absence. Very cool!

A few of my plants look like this poor Pedro. (SS Hutch). He is by far the worst off. Before his recent growth, there was hardly any green on him at all. It looked like a sculpture. We got into a place and I have much better conditions for them all. This one started growing beautiful dark green. Sadly, I've noticed this new spot of cork scar forming.

My thoughts were sunburn.... Then bugs..... Now, a pal on another forum that lives in very similar conditions has suggested it is humidity/bad air circulation and/or poor soil drainage. It's humid and hot here fairly wet too.

I have addressed the air humidity issue by separating the afflicted to a spot near the AC unit. It stirs up the air whenever it's running and fewer pots together should mean less microclimate. It makes sense to me, humidity was likely pretty bad in the previous location where the orig corking issue started. I didn't note it at the time because I thought it was caused by sunburn.

In this case, the soil drains very well. I had repotted the "statue" just before his rebirth. The pot drains well. Unglazed clay pots work best for me, but have gotten pricey as the collection has grown in both size and number. They dry out quicker than plastic. Most of the root rot problems I've encountered were in plastic pots.

My gut still says bug, so I'm asking if anyone here has seen this scourge? Any luck besting it?

Any thoughts about corking being caused by humidity?

I live in a coastal area where the humidity and heat is HARSH. It usually rains about once a day, or at least every other day. Mine are all flourishing. I dunno, probably dumb luck.

I will add that most of mine have been planted in the ground, which is a sandy/soil mixture.

Some of my old, venerable plants have developed a rough, calloused skin, near the base of the plant, that is basically due to maturity. For instance, my Astrophytum ornatum and Euphorbia obesa mostruosa, shown here.





It is pretty hot and humid here in the summer - the peak has now passed, but today it is 83F and 85% humidity. But that doesn´t cause callousing or corking of plant skin.

The corking on your pictured plant is so thick and covers such a large area, even appears to be spreading, that I think it is probably some kind of pathogen - fungal or some other infectious agent. Which if proved to be the case possibly points to some rather drastic measures. Sorry.

Looking through this article Cacti care and looking over all the damage on each specimen... I believe I've got a big suck-combo of several types of damage.

I'm growing outdoors organic ferts and so far chemical free (besides rooting hormone on just a few tiny cuttings). Some pest damage is to be expected. The Hutchenson clone in the picture has not gotten any worse since moving it to a location near our AC unit, which kicks up the air intermittently, so that's good, but not conclusive.

The strong will survive! I will do what I can, but in the end some are thriving and some are not. Eventually a few will get significantly ahead of the rest. At that point, I will know what strains are best suited for my particular climate.

PC already grows fine here and it's got the goods. I'm just not wild about its looks.



Below is another afflicted cacti. This appears to be a combo job with sunburn playing a role. I think fungus as well, based on how it looked before going all ashy white.

i gots some cacti with similar damage, growing in pcnw, there is a lot of not prime growing time for specimens to deteriorate. in my experience, once the damage is done there is noways to undo, the best solution i have seen is chop it up the make baby cuttings and try not to allow the same damage to occur on the fresh growth, although, i dont believe there is any fungus involved on mine, this could be a problem you will need to treat before you will be able to successfully clone those arms...you might be able to cut off the area that is not affected by the fungus yet and grow it separately then just watch the old crusty part and see if it pups out again or dies back?

On some happier news.... Here is a lumberjack clone that came from a Nexian/nooker that I won't name... But THANK YOU!

This sucker seems to really be loving the new yard! The base pup. Was there when I got him a few seasons ago. The whole plant was stalled or slow otherwise. All of the fresh looking growth has happened since March!