There is very little we can do about the two problems that beset our horse chestnuts, leaf miner, and possibly fatal canker, except insure against a future without them. It is by no means inevitable, but we should be prepared.
What to plant to succeed them depends, of course, on what part they are playing. An avenue presents the worst dilemma. There is scarcely ever space to plant another avenue for succession outside the root-zone and the shade of the incumbent
Fell alternative trees and replant in the gaps? It is hard to take such a radical long-term view, but it is probably the best answer. And replant with what? Limes are the safe choice.
To replace a screen of chestnuts, which is what I need to do (they are the only big trees between the house and the village street) I am planting beech under and around the chestnuts. Beech grows quite quickly when its young and demands less light than other candidates. By planting the trees small and quite thickly I hope they will be forming an almost hedge-like screen (though not cut as a hedge) by the time the horse chestnuts succumb – if they do. Then I shall be able to choose the best beeches – some may well be damaged by falling timber – and train them up as worthy successors.
