The rise of Biodiversity Net Gardening
A year into mandatory BNG, our Head of Consultancy, Jon Collins, discusses concerns that target-driven habitat management may harm nuance, creativity, and chaos.
One of the singular joys of BNG and Habitat Banking has been the opportunity to visit vast swathes of countryside that would otherwise have been off limits. This has commonly been to provide initial views on opportunities before leading on to the delivery of Habitat Baseline Assessments, Masterplans and HMMPs by our Ecologists. However, we are increasingly being asked to consider land where the BNG surveys and plans have already been produced, and are looking to deliver 30 years of implementation, maintenance and monitoring.
Perhaps unsurprisingly, turning the theoretical into the practical is not straightforward.
Firstly, there is the subjectivity of the baseline and naturally differing opinions to contend with, and in some instances, facing a seemingly significant shift in condition since the initial baseline was produced. A recent site visit to look at an area of existing Lowland Meadow to be enhanced found over 80% coverage of scrub, although in more positive news, it was teeming with birdlife. Achieving the target condition would be a battle, and one not necessarily of most benefit to wildlife.
On the same site, other neutral grasslands and lowland wetlands have been proposed for enhancement through improved maintenance, either by mechanical cutting or grazing. However, the presence of developing anthills, in addition to other physical constraints, would make machine cutting unfeasible, and the poor quality of the existing sward was a concern for the ability to sustain grazing animals. Underpinning all this is the constant reminder that management needs to achieve the target condition set out within the legal agreement, regardless of these constraints.
A further visit identified a vast area baselined as Mixed Scrub but was found to be over 75% tussocky grassland with scattered semi-mature trees and scrub patches. Considering the work required to achieve the target habitat and condition, it was hard to escape the notion that we were looking at fantastic, developing wood pasture and parkland, only missing a few hardy livestock.
Former golf course sites present a similar conundrum. We have worked with baselines that recorded every patch of grassland, scrub, and scattered trees and then made targeted habitat prescriptions accordingly. But in reality, common sense would suggest a more holistic approach by introducing grazing stock and progression towards Wood Pasture & Parkland, building on the existing landscape structure instead of micro-managing discrete areas for particular target habitats.
These observations led our Head of Grounds & Estates to coin the phrase ‘Biodiversity Net Gardening’—the notion that BNG has the potential to overprescribe and overcomplicate rather than being guided by what is sensible and appropriate for the Site, the Landscape, and Biodiversity.
Author: Jon Collins, Head of Consultancy
Images: Plantlife