Also Johnstone.
Scottish Tartans Society notes: A powerful Border Clan who pursued a deadly feud with the Maxwells. Their stronghold was Lochwood Tower, near Beattock, which was burned down by the Maxwells in 1593. The tartan was first published in the Vestiarium Scoticum in 1842. Before that time Border tartans were generally unnamed. More likely the tartan came from the Aberdeenshire Johnstons, whose family seat is at Caskieben, Blackburn.