Egg shells can attract rats, so some people roast them in the oven first.

Endlessness - those black marks appear sometimes, they're a kind of infection that Trichocereus spp. are more or less prone to. Some of my specimens get it during the cold, dark, damp winter. I'm not sure if it's bacterial or fungal but I've generally dusted it with sulfur powder if it seemed to be increasing too much. Other times where it's stayed small I've gotten away without doing anything to it.

The black spots at or near the meristem have IME been unproblematic outside of the optics. Black spots lower down the stem seem indicative of a more virulent disease which IIRC is associated with incorrect fertilizer applicartion. Either way, it may be useful to think back to what fertilzers you may have applied in the past months.

I've only seen tip damage like that on my cacti from cold damage in the winter. It can take a few days or longer for the damage to be visible after a really cold night. In the spring they grow right through the damage, as long as it is not too severe.

Slugs can also cause damage like that to the tip, though I have no personal experience with them.

In my yard leaf footed bugs will attack the growth tips. They can cause the tips to terminate, and a new pup will form on the tip. They cause some scarring to the tips. But leaf footed bugs don't cause those large black areas of damage like that.

Slugs and snails like to eat the growing tips, which causes my cacti to pup at the top. But when the damage heals it doesn't go black like that, it calluses over like any cut.

Maybe it's cold damage causing rot.

Honestly, I think it might be a mix of both.. In some cases those black spots could be from cold damage, but at the same time I have seen some snails and insects on the cact which could have done some damage too. I guess I gotta hedge my bets and try diatomaceous earth as well as getting/building a better greenhouse for them before end of the year.

Thankfully out of the 200 or so columns growing there, only 4 or so have some minor damage.

Not wanting to step on An!cca's post on the potency of the TBM A/B variety in another thread I thought I'd post here a pic of this one I have. I bought it because it seems to have both A and B. Is anyone else aware of this combo? I keep thinking I'll see another example but haven't yet. Not sure if it's all that rare.

Wolf thats a tricky one. It kind of looks like the short form, but new growth is etiolated. OR it could be long form but older growth was stunted. My guess is that the latter is more likely. I think the long form can look that way.

IME the short form doesn't get long, at least not like the long form does with those spike-free snakelike bits. My TBMs are only short form though so I haven't had the chance to observe the behavior of the long form. Your specimens do give the impression that the long form can get short, Wolfie.

What I did find with mine was that they were longer when I first got them but subsequent new growth had a tendency to be shorter and chunkier. I think there may be something that cactus cultivators do to force longer growth. Mine were in a shallow pot at first - a deeper pot has made them get much chunkier, and with hefty spines too.

Back to Endlessness' discoloration issue, I just stumbled across this snippet as another factor to consider:Here.

EDIT: Ah, but the discussion continued:
(etc.)

One of my minions invited me to a farmer's market where I acquired these lovely specimens.



One love

Happy Shiny Cackatooses! Good find VM!

What were they sold as? With Cristata form I have a hard time differentiating between species.

They were sold simply as San Pedros at both booths I visited. I plan to be staring at a lot of cactus pictures in the coming days to see if I can narrow anything down. And because it's fun.

One love

Looks like my "Scopulicola x Juuls" is going to flower this week.

That's really exciting. Make sure to post when it fully blooms

One love

Pretty sure this is a TPPC, a year old. The first seed that I planted that made it to adolescence. I had a bunch of Macros, but when I moved, I lost them. Like 10 macro starts just disappeared somewhere in the move.



Melvin; a gift from a friend.




Juules' Giant base, Lophophora Williamsii graft. The graft was done about a year ago. Has anyone ever had a Loph graft that went columnar? I'm super confused about this, never seen a Loph grow like that.



This one is a mystery to me, a friend left it behind after staying with me for a couple of months and only referred to it as San Pedro. It's clearly a crest or quasi crest, but I'm not great at taxonomy. Any ideas?




Trichocereus peruvianus quasi crested. Also a gift from a friend. One of my favorites, but it hasn't grown much since I got it, and it seems to have an issue rooting, which is why the rocks are in the top, to keep in from leaning.



A bunch of pereskiopsis that I am growing out for grafting stock



Thanks for checking out my few little guys here. I'm new to growing cacti; only been doing it for a year, so any tips or tricks are greatly appreciated.

This are some Trichos i have (Peruvianus, Pachanoi, Bridgesii, etc)

Likely a light issue so it's grown elongated to reach more light.

Thanks, I'll move it somewhere where the light is better. I was under the impression that Lophophera liked shadier spots.

Flower big as my hand

They do, but they also need a certain amount of light too.

While we're at it, "Melvin" is looking a tad etiolated as well.