Why branches are falling in Cardinham Woods on the calmest days

You are walking one of the trails at Cardinham Woods, near Bodmin. There is no wind. The sky is clear and the afternoon is still. Then, somewhere in the canopy above you, a heavy branch lets go and comes down without any warning at all.

It sounds like the sort of thing that only happens in a storm. It is not. Forestry England has put out a warning about fallen branches at Cardinham Woods, and the cause has more to do with the heat than the weather you can feel.

What summer branch drop is, and why it happens

During spells of hot, dry weather, trees come under stress, and that raises the chance of what is known as summer branch drop. It is when large branches, particularly from mature broadleaf trees like oak and beech, fall without warning, even on calm, still days.

The name is almost misleading, because it does not need a gust to set it off. The pressure builds inside the tree over a long dry period, and the branch can come down when everything around it looks perfectly settled.

A sign of a bigger shift

Forestry England frames the branch drop as part of a wider change to Cornwall’s woodlands. As the climate changes, they say, woodlands are facing new challenges. Hotter summers, wetter winters and more frequent extreme weather events are putting increased pressure on the forests and the wildlife that depends on them.

Trees are resilient, and they do a lot of quiet work. They store carbon, they cool the environment, and they provide habitat for nature. But they are not immune to the effects of prolonged heat and drought, and a long hot summer leaves its mark.

At Cardinham Woods, the response is to keep adapting how the forest is managed. That means monitoring tree health, carrying out safety work where it is needed, and promoting a diverse woodland that can better stand up to future climate conditions.

What to do when you visit

The advice for visitors is simple. If you are heading to the woods during warm weather, be aware of your surroundings, especially when you are spending time near large mature trees.

That is worth keeping in mind if you tend to stop for a picnic or a rest under the biggest, oldest trees you can find, which are exactly the ones most likely to shed a branch on a hot day.

Forestry England says understanding how climate change affects woodlands is part of protecting them. By knowing what is happening to these places, they say, we can help care for them for generations to come.

You can find opening times, trails and parking on the Cardinham Woods page at Forestry England.