It is in places referred to as 'Spring Glee' which tells of its origins, like some other songs in the Copper family repertoire (Dame Durden) as a glee. Glee clubs, still going, were very popular in the late 18th century and through the 19th. They were generally pretty pastoral pieces sung in parts from music. We've discussed this in other threads. The Copper family style of harmony is at least partly based on the idea of glee singing.