Biodiversity Net Gain — Tree & Woodland Planting Support
Urban Tree Management provides arboricultural input to biodiversity net gain schemes — preparing tree and woodland planting plans, planting specifications, and canopy data to support the delivery of BNG planting.
We work alongside your appointed ecologist, who leads the BNG assessment and metric calculation, providing the arboricultural detail that turns a BNG planting requirement into a deliverable, properly specified scheme.
Our Role in Biodiversity Net Gain
Biodiversity net gain assessment and the statutory BNG metric calculation are carried out by a qualified ecologist. Urban Tree Management does not carry out the BNG metric assessment — that is correctly the role of a CIEEM-registered ecologist.
What we provide is the arboricultural input that supports the tree and woodland element of a BNG scheme:
- Tree and woodland planting plans to deliver BNG planting requirements
- Species selection appropriate to soil, site, and target habitat type
- Planting specification — stock, spacing, protection, and establishment
- Canopy cover data and projected canopy growth modelling
- Existing tree and woodland baseline survey data to inform the ecologist's assessment
- Long-term woodland and tree management input for the BNG monitoring period
For the full detail of how we design and specify planting, see our
Tree Planting Schemes
page.
The 30-Year Obligation Changes the Specification
BNG habitat must be secured and maintained for at least 30 years, and that is where tree and woodland planting most often falls short.
Establishment failure in the first three years is common, and a scheme that loses a third of its stock has not delivered the units it was consented on. The obligation does not lapse because the planting died — replacement is normally required, at the developer's cost, years after the contractor has left site.
That changes what a planting specification has to do. It is not enough to name a species and a spacing. The specification needs stock sized appropriately for the site rather than for the budget, ground preparation that reflects the actual soil conditions, protection against browsing and strimmer damage, and an aftercare programme with someone accountable for it — including watering provision in establishment years, which is the single most common point of failure.
We specify planting that will establish, because on a BNG scheme the cost of planting that does not is considerably higher than the cost of specifying it properly in the first place.
Woodland Creation Takes Time to Count
Newly planted woodland does not deliver its target habitat condition on the day it goes in the ground.
The metric accounts for time to target condition, and for woodland that is measured in decades rather than seasons. A scheme relying heavily on new woodland creation to meet its net gain carries a significant time-lag penalty, which means more planting is required than a straightforward area-for-area calculation would suggest.
Understanding that early affects how much land the scheme needs to allocate to planting — and whether on-site delivery is realistic at all, or whether off-site units are the more sensible route. That is a question worth asking at design stage rather than after the metric has been run.
How We Work With Ecologists
Where you have an appointed ecologist leading the BNG assessment, we provide the arboricultural data and planting detail they need — baseline tree and woodland survey data, canopy measurements, and a deliverable planting scheme that aligns with the habitat targets in their metric.
Where you do not yet have an ecologist appointed, we can refer you to CIEEM-registered ecological consultants we work with across the North West.
We also work in the other direction — as
arboricultural subcontractor to ecological consultancies, delivering the tree and hedgerow element of their commissions under their project management and, where required, under their branding.
Does BNG Apply to Your Scheme?
Biodiversity net gain has been mandatory since February 2024, but the exemptions have changed. From 6 August 2026, developments of 0.2 hectares or below are exempt from mandatory BNG — though local planning authorities may still request ecological information, and some are asking for canopy data regardless.
Where BNG does apply and tree or woodland planting forms part of the delivery, the arboricultural specification matters. See our BNG exemptions page for the current position, and understanding biodiversity net gain for the wider framework.
Frequently Asked Questions
Can you carry out my BNG assessment?
No. The statutory BNG metric assessment must be carried out by a qualified ecologist and is not within arboricultural scope. What we provide is the arboricultural input to the tree and woodland element of a scheme, working alongside your appointed ecologist.
What arboricultural input does a BNG scheme need?
Tree and woodland planting plans, species selection, planting specifications, canopy cover data, and baseline tree survey data. We provide all of these to support your ecologist's BNG delivery.
Do you work with ecologists?
Yes — we regularly provide arboricultural input to ecological consultancies across the North West, and can refer you to CIEEM-registered ecologists where you do not have one appointed.
How long does BNG habitat have to be maintained?
At least 30 years, secured by planning condition or a section 106 agreement. For tree and woodland planting that means an aftercare and monitoring commitment well beyond the usual five-year establishment period.
What happens if the planting fails?
The obligation remains. Replacement is normally required, which is why specification and aftercare matter considerably more on a BNG scheme than on ordinary landscape planting — a failed scheme has to be redone at the developer's cost, years later.
Can tree survey and BNG baseline data be captured on the same visit?
Yes, and it is the sensible approach. Capturing both on one visit avoids duplicated attendance, reduces cost, and keeps the arboricultural and ecological datasets consistent with one another.
Does new woodland count towards net gain immediately?
No. The metric accounts for time to target condition, and woodland takes decades to reach it. A scheme relying on new woodland creation carries a time-lag penalty and requires more planting than a straightforward area calculation would suggest.
Biodiversity Net Gain Planting Support — North West & Nationwide
We provide the arboricultural input to BNG schemes — tree and woodland planting plans, specifications, canopy data, and the long-term management detail the 30-year obligation requires — working alongside your appointed ecologist. Independent, Level 6 qualified, and entirely free of any tree surgery contracting interest.
Get in contact with our highly experienced and personable team of arboricultural consultants today, to discuss your requirements and to obtain your zero obligation quotation.
