Clocaenog Forest is in West Denbighshire/Conwy, Wales. It is 40 square miles (100 kmē) in extent, mostly coniferous softwoods under the control of the Forestry Commission. It is a highland region, mostly above 350 metres. It experienced a severe winter in 1946/47 with over 1.5 m of lying snow on flat ground recorded at Clawddnewydd (a nearby village), and there was another hard winter in 1962/63. It is also the last mainland stronghold of red squirrels in Wales.
It was planted in 1905 on what was mostly moorland, and also took up many acres of small farmers land.
ClocaenogForest in North Wales is believed to have the largest population of red squirrels in Wales and is probably their last stronghold.
Because of the concern over the decline of the red squirrel throughout the UK, a project was set up in November 1992 in an attempt to determine the status of the red squirrel population in ClocaenogForest and the influence that the grey squirrels were having on this population.
Research on the red squirrel population is continuing, the area to the west of Llyn Brenig is being surveyed to determine the extent of the red squirrel population and to compare this population genetically with that in the main forest block.
The Newborough forest population is of course not genetically the same as the population in Pentraeth.
In Newborough forest the population is currently extremely diverse, but future levels of genetic diversity will be affected by the number of animals anually present in the population.
Clocaenogforest contains the largest single population of red squirrels, but this is mixed in with grey squirrels, and is therefore vulnerable to disease outbreaks.