Mount Shasta’s official number of eruptions by has been downgraded by one. The Forest Service has released a report that revises a French ship cartographer’s observation of a volcanic plume on September 7th of 1786. Volcanologists have puzzled over the plume because they have never found ash deposits that matched the eruption’s reported dates, and no other records detailing the eruption have surfaced. This month, a team of scientists and historians concluded the plume was not caused by a volcano but likely a grassland fire. So on August 6th, Mount Shasta’s volcanic history book became a little shorter as the 1786 eruption was officially struck from the record. Scientists are correcting the records in order to make more accurate predictions of future volcanic activity.