"If we can get people to keep their trees trimmed it reduces the risk of fires and power cuts.
"When tree owners have not taken reasonable steps to trim their trees that cause damage to the network, Powerco will recover the costs of repairs from them."
Mr Hammond said most power cuts caused by trees could be avoided if owners called in professionals earlier.
"Last year our vegetation contractors removed or trimmed more than 38,000 trees that were endangering electricity supply," he said. "It is important we keep on top of the problem.
"It is much cheaper to have a contractor cut the trees before they cause an issue.
"Government regulations say that if a tree is within 4m of the overhead lines, owners must use an approved contractor to have it trimmed."
Powerco paid for the first maintenance cut when a property's trees or vegetation got too close to the powerlines, but after that the property owners had to ensure their trees were trimmed safely.
If a property changed ownership and had already received a free maintenance cut by Powerco, the new owners were not entitled to a free cut and must pay for the service. Most first-home buyers did not know that, he said.
Mr Hammond acknowledged that some people could be put off by the cost of managing vegetation around power lines, but that a way to avoid such a cost was to plant low-growing vegetation instead.
He said that the cost of getting a tree professionally trimmed is small compared to the loss of a life.
"Some people believe as long as you don't touch a wire, you'll be okay. But that's not true.
"Electricity can jump across objects like tree branches or equipment if they are close enough.
"Trees conduct electricity. So do people.
"Most of the lines around here are at least 11,000 volts - that's more than enough to kill a person."
