I guess the first WASN'T the last I'd need ID help with

[WayneByerly]

I'm beginning to feel like I'm standing on the street corner begging spare change. Because I'm coming here SO often looking for help with ID.

I did a Google Search and looked at pictures of a cactus I have an ID for, and what I see doesn't look anything like what I have.

The ID is Cleistocactus ritteri.

But the cactus I have looks like this. It's 38 inches (96CM) tall and it has has 5 'segments' (blue arrows), 3 joints (red arrows) and is about 4 years old. It was only about 6 inches tall when I got it ... IF age vs growth rates mean anything.

DSCF3328.JPG (138.25 KiB) Viewed 277 times

here's a closeup of a joint

DSCF3329.JPG (163.47 KiB) Viewed 277 times

the spines are long-ish, flexible and rather soft-ish. but here and there, there are stiffer, longer spines that stick out. pardon the spider webs ... it's been outside in the greenhouse and I haven't had a chance

DSCF3330.JPG (164.82 KiB) Viewed 277 times

So whatcha think? Cleistocactus ritteri? Or something completely different?

[stefan m.]

Well, to be blunt, cactus growth is non-linear. For example, my cereus(whatever it is) when propagated 4 years ago, had to cut off the tip(rot). The first offshoot it produced it took 2,5 years to be 15 cm long. Then it broke. It produced a second one, now over 30, wider and sturdier, in just this summer.

[7george]

Bo shrub <>1 m, branching at base; br c. 3 cm 0; ri 12-14 or more; ar 5 mm apart; sp not sharply differentiated; csp 5, 1 cm, yellow; rsp c. 30, shorter, white; flar with conspicuous additional white, bristles 3—4 cm; fl c. 4 cm x 5 mm, lemon-yellow, nearly hairless

It can be C. ritteri. You can count and compare features. In culture plants often differ.