Davidia involucrata dove flowers garden green handkerchief natural nature petals spring tree white woodland England english Great Britain lilac purple spike syringa Apulia asphodel buds Gargano.Puglia Italy stamens wild alpine altitude Austria blue flower gentian high plant remote trumpet diversity flora Greece Greek red roadside verge mediterranean plants umbellifers bush cistus pink shrub ecology habitat yellow background beech Fagus fresh hedge leaf leaves texture young