See the wood for the trees in forestry mystery

A survey being carried out as part of a land management review at Swinnie plantation, revealed an earthwork structure of about 5 acres (2ha), shaped like a jigsaw puzzle piece.

Three puzzle pieces have been found within the local area, all within 5km of each other.

FLS Planning Forester, Tom Harvey, said: “It’s a really odd one. The Swinnie piece is made up of broadleaf woodland species hidden within a crop of spruce trees.

“The jigsaw piece shape is formed by a ‘woodbank’ - a raised embankment that in the very early days of forest management would define the woodland boundary.

"There would have likely been a ditch right next to the woodbank that was intended to protect the trees within from browsing damage.

“On top of and all around the woodbank are mature beech trees that are possibly up to 180 years old, so this feature has been in place for a while.”

The puzzle piece shape is invisible from ground level, with the feature just hinted at in regular aerial imagery, but only became apparent with Lidar analysis.

The puzzle piece shape is invisible from ground level.

However, when the team decided to consult maps and Lidar images held by the National Library of Scotland, things became clearer.

The Lidar images – 3D scans obtained by using lasers to ‘see through’ the tree canopy to identify physical features on the ground – clearly showed the woodbank outline.

And the Swinnie Forest feature, as well as two others, were marked on old OS maps dating from 1863.

Tom added: “We haven’t been able to track down any information about who planted these woodlands or why these woodbanks are in such an unusual shape, so we’d love to hear from anyone who can shed some light on this intriguing puzzle.”

Anyone with any information can contact the team at [email protected]