Lilacs seem to know nothing of winterkill. This long harsh winter was as nothing to these ancient lilacs. The same cannot be said for the wisteria. Winterkill in its most serious form has hit here. There is always a little winterkill, but there should be some sign of life by this time in the spring. No such luck. This might very well be the end of the wisteria as the provider of shade on the piazza. The Thomas…