Woodland Trust Scotland is to plant more than 200,000 trees in a project worth more than £1m and drawing stock from a host of suppliers.
Contractors and volunteers will create the 250ha native woodland in a sheltered glen and rugged moorland at Lang Craigs in west Dunbartonshire. The trust bought the land last year and is building a deer fence to protect the young trees.
"Main contractor UPM Tilhill will do the bulk of the planting but the trust has allocated special areas for planting by schools and volunteers," said a trust spokesman, adding that a list of suppliers was being finalised.
"We're planting a mix of native trees including Scots pine, ash, birch and oak, and will source the trees from a variety of nurseries. The project has been supported by a £1m grant from the Scottish Government's rural development programme."
Contractors overcame an early obstacle to protect wildlife. The route of the fence had to be altered to protect an otter hover discovered during survey work on the western side of the site, said site manager Roy Barlow.
"We made some changes to the route of the fence to avoid disturbing the hover - a temporary home they use like a motel when crossing the area. We've changed the design of our watergates so otters can get through the fence where it crosses burns.
"Animals like otters need to be able to move around to find food and mates so protecting the routes they use is really important and needs to be considered when undertaking large planting and fencing jobs like these."