Work is taking place at South Barrule Plantation to remove storm damaged trees.
DEFA expects the work to take several months to complete, with fencing and public notices in place to show any diversions or restrictions.
The department said it's aiming to keep the main forest roads open, but some restrictions will apply at times.
The Viking mountain bike trail will be closed throughout the works.
South Barrule's outdoor activity businesses will operate as normal.
Microwave food leads to early hours callout for firefighters
Food burning in a microwave sparked a callout for Island's Fire and Rescue Service this morning.
Vigil to mark three years of war in Gaza
The Island branches of Amnesty International and the Palestine Solidarity Campaign will be holding a vigil next month.
Your chance to vote for Island in travel awards
You're being urged to help the Island take home a prestigious travel award.
MHKs to elect speaker and deputy this week
The new House of Keys will sit for the first time in the political year next week.
FOI answer 'could undermine prison security'
The Department of Home Affairs says giving out information about prison staffing and procedures would undermine security at the Jurby facility.
Police launch appeal after broad daylight attack in Douglas
Police are appealing for information after a man was attacked in Douglas last weekend.
Yellow weather warning issued for Sunday
Ronaldsway Met Office has issued a yellow weather warning for the weekend.
Ghost hunters report spectral child's voice in Castletown tea shop
An investigation into whether a Castletown tea shop is haunted has proved inconclusive.
