The cost of replacing felled mature trees along the planned NGT Trolleybus route in North Leeds could be as much as £14 million, according to an independent tree expert.
But transport chiefs, who dispute his figures, will replace them with smaller trees worth just £700,000.
Arboricultural consultant Sam Turner was commissioned by a local residents’ group to carry out the survey, using methods employed by councils to evaluate trees.
Some 500 trees, many of them mature, will be cut down if Trolleybus is given the go-ahead. Transport chiefs have pledged to replace felled trees on a three-for-one basis and to replace any replanted trees which die within the first five years, but residents fear the impact will negative.
Mr Turner said: “ The calculation depends on a number of factors, including how old the tree is and where it is. A mature tree in a prominent position on a roundabout, for example, would be worth more in monetary terms, than one of similar age in the middle of a wood.
“Some of the mature trees I viewed on part of Otley Road I estimate to be worth around £50,000.
“The plan is to replace them on a three-for one basis but the trees they put back will not be as mature as some of the ones they take out, so in terms of giving the same benefit, we may have to wait 50 years or so for that.”
Mr Turner was commissioned to undertake the report by Drummond/Churchwood residents’ association, whose members are opposed to the controversial transport scheme.
Alison Larkin, from the group, said: “We are concerned about the impact of tree loss all the way down the NGT route.”
She said trees were important for stemming noise pollution, reducing storm water run-off and cutting carbon dioxide levels.
A Metro spokesman said: “The CAVAT method reflects a tree’s contribution as a public amenity and cannot be used to calculate a tree’s replacement cost.
“In his report Mr Turner has ascribed a value to the replacement trees on the day they are planted, rather than when they have reached any maturity.
“The NGT scheme proposes to plant over 1,700 replacement trees and over 60,000 square metres of woodland.”