Hello Paul I have an Elizabeth Trickey marrying Samuel Gillard in 1761 in Culmstock on my tree. I am of the understanding that the Gillards were most likely Huguenot refugees from France and that it is quite possible the Trickeys were also with their name derived from Tricquet (or Tricault).
Do you have the above Elizabeth on your tree ? By the way the local river is the River Culm(not Culmstock). Regards Peter Chard Australia