While September is technically an autumn month according to the meteorological calendar, experience suggests it usually provides scope to savour the last vestiges of summer, writes Erin McDaid of the Nottinghamshire Wildlife Trust. According to the astronomical calendar, summer ends on September 22 this year. After the somewhat mixed bag of weather we’ve had so far, I’m planning to eke summer out as long as possible — although the weather over the past few days hasn’t filled me with confidence. Whatever the weather, Mother Nature clearly signals September’s seasonal segue as hedgerows become h…