ST. PETERSBURG — Black power lines snake through the big oak tree in Terry Dinninger's back yard.During Hurricane Irma, he and his wife watched the gnarled limbs swat at the wires and wooden pole, sending up a fountain of sparks.The storm cast Dinninger and his neighbors in the city's Jungle Terrace neighborhood into muggy darkness. He remained that way for a week.Dinninger blamed Duke Energy for failing to keep the trees trimmed."A lot of the outages could have been non-existent had there been proper maintenance to the lines," he said. "My yard is living proof they haven't done a damn bit of their job on these trees."More than 520,000 customers lost electricity in Irma across Pinellas and Pasco, two of the hardest hit counties in Duke's service area. Angry residents saw fallen branches and wires everywhere — evidence, they thought, that Duke should have been better prepared.A Tampa Bay Times review of state filings shows that the company cut its tree-trimming budget in the area by more than $2 million last year, from $9.9 million to $7.4 million.For comparison, Tampa Electric allotted $10.7 million for tree trimming. That's $3.3 million more than Duke in an area with only 60,000 more customers. It had 200,000 fewer outages immediately after Irma.Would an extra $2 million for tree trimming have made a significant difference?"To the layperson, the answer is yes," said Pinellas County Commissioner Ken Welch, who previously worked for Florida Power Corp., which was bought by Duke. "I certainly hope they will reassess their tree-trimming budget."The company defended its preparations, saying budgets vary yearly according to needs across the system."Our program works," said James Bent, Duke's director of vegetation governance. "We go through normal (budget) fluctuations year over year. … 2016 may have been a little lower, but there's been other years it's been a little higher."• • •Hurricane Irma chewed up the power grid across most of Florida, leaving an unprecedented 6.7 million customers, nearly two-thirds of the state, in the dark.The storm knocked out electricity to about 78 percent of Pinellas, more total customers than anywhere else in Duke's service area. And it could have been worse; Irma weakened significantly in the hours before it struck the Tampa Bay area.Many of Duke's customers, who already pay some of the highest rates in the state, were shocked by the number of outages and how long it took in some areas for power to come back on.Dwight Dudley, a former St. Petersburg state representative often critical of power utilities, said Duke needs to be able to handle a Category 1 storm like Irma without more than three-quarters of its local customers losing power. He added that a crew came out and trimmed trees in his alley only after the hurricane knocked out power, timing he found bitterly ironic."This is the new millennium. We have science and technology. We can do all kinds of things, but we can't manage the debris? We can't do vegetation maintenance better?" said Dudley, a Democrat. "If you're granted the right of monopoly in our state and you're allowed to make billions upon billions from consumers, then you need to step up your game."In St. Petersburg, according to the mayor's office, a resident complaint app registered about 650 reports related to "tree-trimming/removal" or "storm-related requests" since the weekend of the hurricane. The city cannot parse how many specifically mentioned Duke Energy or power lines."Hurricane Irma clearly identified the need for there to be more distance between tree branches and power lines," Mayor Rick Kriseman said in a statement, adding that the city will be mindful of tree planting and will work with Duke "to ensure proper maintenance" in the future.Of the four Duke Energy Florida regions, South Coastal — the section composed of Pinellas and Pasco — has the biggest annual vegetation management budget. It was more than $9.5 million for each of the three years before dropping off in 2016. The projected budget for 2017 called for even less spending.Bent said Duke is careful and thorough about maintenance. He was not worried that Tampa Electric budgets more for tree-trimming around its distribution lines. "More dollars doesn't always translate to more work or better work," Bent said.Duke enhanced its vegetation program a few years ago, he said, expanding the right of way for clearing trees and boosting herbicide spraying to cut down on future growth. Not all of that work, he said, is reflected in the annual trimming budget.Crews typically cut branches on three- or five-year cycles, he said, focusing on areas with a history of outages and where more customers live.Not all trimming is Duke's responsibility, either. The company typically handles trees within about 20 feet of transmission or distribution lines. It has easements that allow workers to access poles and wires, even if they are on private property. Service lines, which extend directly from poles to houses, are the responsibility of homeowners.Duke said in state reports that it cannot determine how many of the outages in a hurricane are related to tree damage without "extraordinary effort and considerable conjecture." Instead, all of those outages are labeled as storm-related. Customers will likely never know just how many of the Irma outages were caused by trees.• • •What's next? Probably a hike in electric bills.Duke does not yet know how much it has spent on recovery from Irma, but the company will soon ask the Florida Public Service Commission to approve a surcharge for the cost of cleanup, said J.R. Kelly, the public counsel who represents the state's utility customers.Florida Power & Light got permission for a surcharge of about $3.36 per month on average household bills after Hurricane Matthew raked the east coast last year. Customers began paying it in March, and the charge — covering more than $300 million in FPL's recovery costs — is expected to last a year.Public service commissioners have said they will review the effects of the hurricane and the power companies' performance, including tree-trimming. Politicians on both the federal and local levels have vowed to watch the commission closely. "We're going to want to hear from the PSC and the utility companies as to the relationship between the maintenance and the tree-cutting and how it relates to downed power lines," said state Rep. Chris Sprowls, R-Palm Harbor, who will serve on a special House committee examining preparedness after Irma.U.S. Rep. Gus Bilirakis, another Palm Harbor Republican, said in a statement that he heard complaints from constituents about tree-trimming before the storm."This is one of the many issues I intend to raise with the leadership of power companies during our upcoming meetings," Bilirakis said.St. Petersburg City Council member Karl Nurse said everyone — Duke, municipal crews and residents — need to review if they did enough tree pruning before Irma."I think it's self-evident that their tree-trimming was less than needed," he said. "You sort of want to ask Duke, 'So what did it cost you to restore power?' And that number's got to be big. I don't think anybody saves any money by reducing their tree-trimming budget."Times senior news researcher John Martin contributed to this report. Contact Zachary T. Sampson at [email protected] or (727) 893-8804. Follow @ZackSampson.