They can't. They're doing something, but they aren't having a lot of success with it. See: https://www.kqed.org/news/11767619/monitors-spot-check-of-pge-wildfi

They can't. They're doing something, but they aren't having a lot of success with it. See: https://www.kqed.org/news/11767619/monitors-spot-check-of-pge-wildfire-safety-effort-finds-missed-trees-recordkeeping-errors https://www.kqed.org/news/11767619/monitors-spot-check-of-pg... > In his report, Filip said that by late July, his team had inspected more than 1,550 PG&E vegetation management projects covering about 71 miles of the utility's power lines. That's a tiny fraction of the utility's more than 100,000 miles of distribution and transmission network. About 25,000 miles of those lines runs through areas the state has identified as high fire-threat districts. > In more than 400 cases, the monitor's team identified what Filip termed "potential exceptions" — nearly 3,300 trees that needed work or should have been considered for removal but were missed by PG&E's enhanced vegetation management program. Report: https://assets.documentcloud.org/documents/6272392/Monitor-s-Report-on-PGE-Vegetation-Management.pdf https://assets.documentcloud.org/documents/6272392/Monitor-s...