Opuntia experts chime in

[Andy_CT]

This one is labeled O. polyacantha var. erinacea. I was under the impression that var. erinacea can't be grown here without protection long term, it is not known for its moisture tolerance at all. I think var. hystricina would seem more likely but could it just be a Western var. polyacantha?. btw, not my plant.

[peterb]

That's a good looking one for sure! I am notoriously bad at this group of plants except for the most extreme of the various forms, also easier in habitat since many of the forms are geographical. But I think this looks like hystricina.

peterb

[A. Dean Stock]

Putting a varietal name on an O. polyacantha out of habitat is a real challange but I doubt that it is var. erinacea. It has a lot fewer spines than anything I've seen around here. Looks more like a northern hystricina or even a polyacantha. The fact that it is winter hardy in your area gives a clue as to the origin in a general way.
Dean

[Andy_CT]

Ok, I was on the right track all along.

Here's number 2:

This one is labeled O. basilaris. Its clearly not O. basilaris or any variety of it. The pads are about 5-7 inches long, fairly plump, no visible spines. Really nice yellow flowers. This thing flowered its head off in New England and doesn't have a mark on it from cold or wet. O. aurea species or hybrid?

[peterb]

what a beautiful plant. No idea in creation what it is.
I don't imagine aurea surviving a Connecticut winter. But could of course be wrong.

peterb

[A. Dean Stock]

Looks like an O. aurea hybrid but could be just straight O. aurea. Certainly not O. basilaris with flowers like that. Many of the high altitude ones are plants with smaller pads than this one but some of the ones lower down north and west of Kanab are as large, espcially in cultivation. O. aurea occurs to nearly 9,000ft on high plateaus north of me. Very winter hardy species surviving in deep snow for many months. My all time favorite winter hardy Opuntia. A great many O.aurea in cultivation are actually hybrids that have been backcrossed in hybrid swarms. The ones with pink flowers are introgressed with either O. polyacantha or O. pinkavae. Unfortunately, the type locality for this species is also a hybrid zone (x O.pinkavae).
The name on this plant may be a result of it being confused as being a var. of O.basilaris for some years.
Doesn't look like it set any fruit; no dry pods on it. Most of my "straight" O.aurea are very fertile but the hybrids often have aneuploid chromosome counts and variably reduced fertility.
Dean

[Andy_CT]

number 3:

Another O. polyacantha, I think. Would this be var. rhodantha?

[peterb]

Excellent info on aurea, thanks! I have not read anything very clear on this whole complex of plants, including pinkavae. Found some interesting hybrids (?) or maybe just aurea in Meadview AZ last spring, in this thread:

http://www.cactiguide.com/forum/viewtop ... t=meadview

[daiv]

I am very grateful to you guys for this information. There is so much to learn about these.

I've seen O. poly's all over the country and I've never really known what was going on below the species level with any of them.

[A. Dean Stock]

That last O. polyacantha is probably var. polyacantha. The name rhodantha is not currently an accepted name for any population of O. polyacantha.
The O. basilaris like form from near Meadville (where is that?) is not O. aurea or O. pinkavae. I doubt that it is related to O. aurea as that species is narrowly restricted to southern Utah with hybrids occurring just over the border at Pipe Springs. O. aurea always has yellow flowers unless hybridized. The Meadville plants look to me to be O. basilaris derived and are likely a local hybrid with O. polyacantha. I'd love to get one to do chromosome counts on.
Dean