It is unlikely Kinbote ever
went to look at the famous trees himself (unless there were young
gardeners around),

Well, on p.228, PF, Penguin, 1991, the nasty commentator says of the gifted gardener that:

 

"He stood at the top of a green ladder attending to the sick branch of a grateful tree in one of the most famous avenues in Appalachia. .... We conversed, a little shyly, he above, I below."

 

I concede that Kinbote may not actually have been looking at the trees, or could name their species accurately, although he did take the trouble to enumerate "a few kinds". Or is the whole of the note to line 998 pure invention from beginning to end, composed in vacuo and in pensive mood, an emotion recollected in tranquillity, flashing within his inward eye?

 

Charles