Paul in Essex wrote:What does the forum offer that this one doesn't, may I ask?

Censorship of the word "evolution".

DawnGardener wrote: Do you know what this plant is called?

There is a label ... :
Chamaelobivia [something] Charm. Could it be 'Lincoln Charm'?

DawnGardener wrote: Would you be able to suggest an insecticide I can buy?

Insecticides will not help much, you need a miticide. I don't know what's available in the UK though.

mistyhiss wrote:I drown them every day but if I go even one day without spraying the plants with water they come back.

Is that soapy water? I have never managed to kill mites with just water.

Pia wrote:Do these empty cups fall off by themselves?

Yes, they dry up and fall off. I don't remember how long time it takes, two weeks perhaps.

The stock looks like Euphorbia , which makes sense as the scion is Euphorbia lactea.

R. cereuscula or something similar. It grows long, thin stems ending with clusters of shorter stems.

It happened to one of mine once:

My Opuntia fragilis clones have never produced any fruits, I don't think they are self-compatible.

E. duncanii?

Greenlarry wrote:Is the first one an Astrophytum?

No. Stenocereus pruinosus, I believe.