[split] f35v parallels "oak and ivy"

[MarcoP]

JKP: yes, but then again I have the impression that if there's one thing the VM finds important, it's the leaves. I just don't see why exactly the berries of ivy would be singled out. Even in images of grape plants, the leaves would usually be featured, whether it be in antiquity or the middle ages, in decorations or otherwise. 

If this is one of the Indian plants, of which I believe there are a few, then it might be an important one for trade. For example, pepper was grown on trees (a commenter on Nick's site once proposed this could be pepper, can't recall his name at the moment). Pepper was, and still is, encouraged to climb on other trees and was also found like that in the wild. Not in the ivy-parasite way but in the grape-support way. If it's pepper though, or anything similar, I see no way to confirm it until we can read the text, since we've only got the berries...

Black pepper looks like a good candidate to me too. In any case, we cannot be sure until we read the text. One can also hope to find a better parallel for this illustration in other sources: I think this is something that might still happen.

Anyway, the reasoning would be then that whoever first composed this drawing used the "oak is host tree"-trope as a template and adapted it to add the other vine. This of course assumes that the oak pairing was present in the now lost sources that may have been common to the Italian herbals and the VM alike.

Rene, Touwaide and Clemens seem to agree on the fact that the VMS "Oak and maybe ivy" is particularly close to Manfredus De Monte Imperiali BNF Lat 6823. This manuscript derives from Egerton 747 but (as you wrote above) in Egerton 747 the host tree is "something that might be oak". In the BNF ms it is definitely oak.
You speak of lost sources common to the Italian herbals and the VM which must be assumed. This can seem obvious to you, but I think that it must be explained more clearly. In particular, it is at variance with what art historians believe. It does not seem to me something that can be supported by a casual "of course".

I guess these lost sources account for the "definitely oak" feature, so they where not involved in the production of Egerton 747, right?
Why exactly can't BNF 6823 just derive from Egerton 747 as scholars normally assume?
Why can't the template of this Voynich illustration just be BNF 6823?