Complex sentence: It was decided that Upshur County, Texas would celebrate the yam-a quarantine, placed in the last 1920s due to a weevil infestation, had recently been lifted, allowing the previous cash crop to once again thrive.
Split into simpler sentences: It was decided that Upshur County, Texas would celebrate the yam. A quarantine, placed in the late 1920s due to a weevil infestation, had recently been lifted, allowing the previous cash crop to once again thrive.