What is changing

When land is developed, the law has, since 2024, usually required a small boost to nature — a “Biodiversity Net Gain” of at least 10%. In plain terms, a development is meant to leave nature a little better off than it found it.

From 6 August, the smallest sites — those of 0.2 hectares or less (about 2,000 square metres, roughly a third of a football pitch, or a small cluster of houses and their gardens) — no longer have to do this at all.

For hard-pressed small builders, that is a welcome simplification. But there is a catch for trees.

Why trees are caught in the middle

Under the old rules, removing even a single tree was usually enough to bring a small project into the nature-boost system — because of the way a tree’s protected “footprint” is measured. In practice, that meant a developer could not quietly fell a tree on a small plot without having to make good the loss.

The new rule swaps that “what is the impact?” test for a much simpler “how big is the site?” test. If the site is 0.2 hectares or smaller, the nature rules simply do not apply — however many trees are cleared.

What that means on the ground

On a site right at the new limit, the equivalent of up to 48 small trees — or around a dozen mature ones — could be removed with no requirement to replace or compensate for them under this system. And the trees most exposed are exactly the ones we tend to notice most: established trees on small urban and infill plots.

What still protects trees

It is not a free-for-all. Tree Preservation Orders, conservation-area rules and the special protections for ancient and veteran trees all still apply — they sit entirely outside this change. Some councils also have their own local tree policies: Bristol’s Tree Replacement Standard, for example, still requires replacement planting whatever the new exemption says.

The snag is that these local protections only exist where a council has actually put them in place — and not every council has.

Why it matters

The change is a sensible piece of red-tape reduction for small builders. But it is also, almost by accident, a real step back for the everyday trees that give our neighbourhoods shade, character and wildlife. From August, whether the trees near you are protected will depend less on national nature rules and more on whether your council has its own policies — and on whether a particular tree happens to be covered by an order.

If you value the trees around you, it is worth asking your local council what protections are in place.

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We have set out the full detail — the mechanics, the legal position, and what to watch next — in an accompanying briefing note.

Read the full briefing note here.