KETCHUM, Idaho (AP) — The U.S. Forest Service and Sun Valley Resort have started a tree-thinning project at the ski area on Bald Mountain.

The Idaho Mountain Express reports  that 25 acres are being thinned in one area this year and that about 182 acres will be thinned during the next three to five years.

Ketchum District Ranger Kurt Nelson says the thinning will take out trees killed by insects as well as infected trees while preserving healthy trees.

Jack Sibbach of Sun Valley Resort says the project is also intended to make the mountain better for winter recreationists by creating more space on ski runs.

The project is being paid for by Sun Valley Resort and grants from the U.S. Forest Service.

Officials say a cost estimate hasn't been made.