early spring and late summer
winter
early spring and early autum
The best time to prune an Olive Tree is soon after the fruit has been harvested when the tree is in a more dormant state. Here in Spain many trees are pruned at the same time as the fruit is being picked often with branches cut then shaken for the Olives.
The best time to replant a silk tree would be in late February or early March. You can prune the tree a few months before the move.
in the dead of winter when growth is most impeded.
Probably when the flowers have died off.
I would guess that the best time to prune the tree would be after any chance of frost is over, but before the tree blooms. Otherwise, you risk cutting off the young fruit and will have year of few or no grapefruit. Most citrus matures in November-December.
The Chestnut Tree was created in 2007.
If you mean a beech hedge then August in the Northern Hemispere is best. If it is a tree there should be no need to prune it other than to shape it and you can do this at any time. If you do that too often it will become a hedge and be best done in August.
When all the leaves have fallen, as the tree becomes less likely to be traumatised by the move.
A horse chestnut tree!
Your English is incorrect, should read, "How do you prune an olive tree?"