The tree removal, which started on March 7, is scheduled to finish today at Mt Dewar Station.
Wakatipu Wilding Conifer Control Group manager Briana Pringle, a Queenstown Lakes District Council parks officer, said Douglas fir trees and other wilding species, such as larch, were being removed.
In 1954, there were only three wilding trees on Mt Dewar Station but because of increased seed sources and the gradual reduction in stock numbers, the trees now covered many hectares of the station, particularly on the lower front faces.
She called the trees' spread "exponential''.
"To effectively stop this spread and protect the golden tussock faces of Mt Dewar, Skippers Saddle and Coronet Peak, more aggressive control is required by targeting the large seeding trees across the station's lower front faces.''
She did not have a final cost for the operation.
A $54,000 grant from the Lottery Grants Board's environmental and heritage fund is being used, while Ms Pringle's group and the landowner will also contribute.
