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the trees are forming a low inisde the garden hedgerow, and are still fairly young, they have not been trimmed yet so it is nothing to do with them being cut back too hard. We don't have neighbours to offend Hopkirk, thank goodness, but would plant them anyway if they are for sale as they are ( or were) quick growing !!!!!! It looks like some sort of disease and will have to take a trip around the garden nurseries to see if they can shed some light on it . Thanks for your answers folks.