Pacific Gas & Electric said its equipment may have been involved in the start of a small wildfire that merged with the massive Dixie Fire now threatening homes in Northern California mountains. The U.S. Forest Service was examining a tree found on PG&E power lines near the town of Quincy in Plumas County where the Fly Fire began July 22, according to the PG&E’s report to the California Public Utilities Commission. The smaller blaze burned through more than 6 square miles (15 square kilometers) of forest before combining with the much larger Dixie Fire two days later. Two weeks ago, PG&E told regulators that the Dixie Fire may have been ignited July 14 when a tree fell on another one of its power lines near the Cresta Dam, west of where the Fly Fire started later.