Sheep’s Green and Coe Fen, Cambridge – 2018 Veteran and Ancient Tree Survey

Project Description

Sheep’s Green is situated to the west of Coe Fen and runs along the west bank of the River Cam. It is an ideal place to walk and get away from the busy city streets. Classed as a Local Nature Reserve, the Fen is managed to encourage an increase in natural diversity, and it is intended to remain as a water meadow habitat with periodic flooding. For six months of the year, April to October, Sheep’s Green is grazed on by cattle and at times, horses.

A total of 67 trees were surveyed, comprising 50 ancient and, or veteran trees and 17 ‘advanced candidate veteran’ trees. The survey applied a specially enhanced adaptation of the English Nature’s Specialist Survey Method (SSM). This system was originally designed by Treework Environmental Practice for English Nature (now Natural England) for collecting data on the habitat attributes of veteran trees and is adaptable, having a range of levels of detail of survey information (Levels 1 to 3). Treework Environmental Practice has further developed this system to include scoring systems for the quantities of habitat and associated organisms observed, as well as an arboricultural viability assessment and a veteran tree management module. These latter techniques have also been applied to the current survey population of the Veteran and Ancient tree population at Sheep’s Green and Coe Fen.

The survey highlighted that the veteran and ancient trees on the site are species-rich for epiphytes with a considerable presence of invertebrates in half of the trees surveyed. Key threats to the viability of the trees included structural failure during strong winds, competition from adjacent vegetation, cattle poaching and soil compaction. Recommendations have been made to address these threats.

The detailed tree information, collected using our proprietary MyTrees GIS, indicated a robust population of veteran and ancient trees, with healthy and numerous cohorts of ‘premature and advanced candidate veteran’ trees for which management to reduce risks of declining vitality and structural failure, can produce significantly improved viability.

With reference to relevant, local publications* and the findings of our survey, we were able to support the client with their long term aim to establish an overarching management objective for each of the 67 trees. These Management Operations are specified to support each tree in terms of their stability, vitality and, or continuity of the habitat provided.

Treework Environmental Practice continues to support clients with tree surveys and long-term tree management plans for ancient and veteran trees. Further case studies and resources to help manage ancient and veteran trees can be found in the Treework Library here.

* Sheep’s Green and Coe Fen Revised Management 2012-2021; Cambridge Historic Core Appraisal 2016, Draft (Coe Fen and Sheep’s Green) and the Local Nature Reserve citation.