Project: Decompaction around ancient trees
Client: The National Trust
Contractor: Terrain Aeration
Around 130 ancient trees that form part of an 18th-century landscape near Newcastle-upon-Tyne have been given 1m-deep aeration treatment as part of a restoration scheme.
Gibside's 0.8km-long avenue lined with oak, sycamore and lime trees, known as the Long Walk, required decompaction following an increase in visitors to the site.
Gibside's landscape gardener Keith Blundell said the trees were suffering from the soil compaction resulting from visitor pressure.
"The trees are at least 150 years old," he said. "Some were suffering from stress with crown die-back and nutritional problems."
Suffolk-based tree and sports turf aeration contractor Terrain Aeration worked at Gibside for three days injecting compressed air, via a probe, 1m below the surface. The aim was to create underground fracturing and break up the compacted soil.
"They worked between the drip lines of the trees and needed to use a JCB hammer to insert the probe most of the time because the ground was so hard," said Blundell.
Terrain Aeration managing director David Green decided to use the company's most powerful machine, the Airforce Terralift, following a site visit.
Working at 2m spacings, the company decompacted around the trees and grass of the Long Walk before continuing treatment in the walled garden.
Dried, milled seaweed was injected on the final air blast to keep the new underground air channels open and add nutrients.