I was born in Hassall Green. Fields Farm is a traditional brick 19th century farm complex of house and shippon (local term) but there was a much earlier timber-framed farm dated to 1638 just across the road, now sadly gone. Fields Farm is relatively close to the hamlet of Hassall Green and therefore the term that you used (Hassall Green Fields) may well reflect the ribbon of houses that formed the original settlement. Hassall Green was first mentioned in the 14th century thus has a long history of settlement. There was a salt works here (Roughwood) in the late 17th-eraly 18th century. The T&M canal in the 18th century brought a new wave of building and during the 19th century helped to drive the development of chemical works in the next hamlet called Malkins Bank. (Malkins Bank is not in Hassall Green, this was always a source of local rivalry !)
As a child, I was told that the houses in Hassall Green in the ribbon development alongside the road were half-timbered, these were replaced with post-war housing for displaced families (WWII). The Methodists built a chapel in 1858 to "tame" the unruly residents, they had a reputation for cock-fighting ! A Methodist school followed in 1874 and this was the last Methodist school in the NW when it closed in the early 90s.
Let me know if I can help further
DrD