Last spring our 30 year old wysteria had loads of buds. We had the house hot water pressure washered which apppears to have killed the buds. Underneath the bark, the wysteria is green and very much alive and in places has come to life very well. The majority looks dead. When we pruned it last autumn we took out ca. 80% dead wood some of which had woodworm(!) but we want advice as to how to proceed please?