The Briar Line

[Clemans]

Does anybody have any information on the "Briar Line"?

I have seen a reference (specifically to the upper Arigna valley) that suggests that potato crops "above the Briar Line" were less prone to the blight. I am assuming this is something to do with the micro climate in the hills?  Does anyone know of any maps depicting the Briar line?

Clemans

[gaffy]

I cannot see any newspaper references to it.  But the first thought that comes to mind is that it's the altitude above which briar ceases to flourish in hilly / mountainous areas... a bit like the notion of the tree line.

Added:  It pretty well implies same here: "Many people from the surrounding area fled to those mountains so that they could live above the "briar line," the briar, it was believed, having been the main carrier of potato blight spores."

https://www.sligoheritage.com/ArchBlack47Keadue.htm