You are quite correct. The Ashmeads seem to have originated in a very specific are of Gloucestershire. There is also an Ashmead Mill listed in this area.
My branch of the Ashmead family were also connected to Tidenham in Gloucestershire. My ancestor, Col. Thomas Ashmeade had two younger brothers who came to Jamaica with him in 1788. One of them, Dr. Henry Ashmeade (1772-1821), named one of his coffee plantations in Jamaica Tidenham, after Tidenham in Gloucestershire. There is a farm called The Mead, at Tidenham in Gloucestershire, which is said to be connected somehow to the Ashmead family. Does anyone know what the connection is?
I shall look through my notes and see if I can find the Elizabeth Ashmead who married Joseph Merry at Bisley in 1677. By the way, do you have any information on Ashmead House? I have been trying to obtain a history of the house and also a picture of it, but no luck so far. I would like to try and visit the house on my next trip home to England. My branch of the Ashmead family used to own "The Moor", near Charlton Kings, in Gloucestershire.