The Creepy Things Living in Your Trees (And Why They’re Actually Good)

As Halloween approaches, gardens are filling up with pumpkins, cobwebs and the occasional skeleton hanging from a front door.

But look a little closer at the trees in your garden and you might find they’re already home to some rather spooky residents of their own. 👻

Bats hiding in cracks. Insects burrowing through deadwood. Fungi appearing from old trunks. Birds nesting inside dark hollows.

It might all sound slightly creepy, but many of these things are a completely natural part of a healthy garden ecosystem.

In fact, an old tree can be home to an extraordinary amount of wildlife.

🦇 Bats hiding in trees

It doesn't get much more Halloween than bats.

Trees can provide important places for bats to roost, particularly older trees with cracks, splits, cavities, loose bark and old woodpecker holes.

And you might never know they're there.

Some potential roosting spaces can be surprisingly small and difficult to see from the ground, which is one reason trees need to be properly assessed before certain work is carried out.

All UK bat species and their roosts are legally protected, so signs that bats may be using a tree need to be taken seriously.

🕷️ Deadwood that's surprisingly full of life

A dead branch might not look particularly exciting.

To wildlife, however, dead and decaying wood can be incredibly valuable.

It can provide food and habitat for beetles, insects and other invertebrates, which themselves become an important food source for birds and other animals.

Fungi and microorganisms also help break the wood down, returning nutrients to the surrounding environment.

So while we call it deadwood, there's often plenty of life going on inside it.

🍄 Strange fungi appearing from the trunk

We've covered this one recently, but autumn is prime time for spotting some particularly strange-looking fungi.

Brackets growing from trunks, mushrooms appearing around roots and unusual formations emerging from old wood can certainly give a tree a slightly haunted appearance.

Some fungi simply break down dead organic material, while others can be associated with decay in living trees.

That's why seeing fungi doesn't automatically mean a tree needs to be removed.

The type of fungus, where it's growing and the overall condition of the tree all matter.

🕳️ What's lurking inside that hollow?

A hole or cavity in a tree can look alarming — particularly when you can't see what's inside.

But hollows can develop naturally as trees age and may become valuable habitat.

Depending on their size and location, cavities can provide shelter for birds, bats and a huge range of insects and invertebrates.

And here's something that surprises a lot of people:

A hollow tree isn't automatically a dangerous tree.

Trees can sometimes continue growing and adapting around cavities for many years.

Whether a cavity affects the structural condition of the tree depends on far more than the fact that there's a hole in it.

🦉 Whoooo lives there?

Sorry. It is Halloween. We had to. 😂

Tree cavities and dense canopies can provide important shelter and nesting opportunities for birds.

Some species make use of existing holes and cavities, while woodpeckers can create their own.

This is another reason arborists need to consider more than simply the branches being removed when carrying out tree work.

Wild birds, their nests and eggs have legal protection while nests are active.

💀 When 'dead' doesn't mean it has to disappear

Deadwood is an important part of the natural lifecycle of trees.

Where it can safely remain, retaining some deadwood can provide valuable habitat and contribute to biodiversity.

That doesn't mean every dead branch should always be left in place.

A large dead limb hanging over your driveway, house or a public footpath presents a very different situation from deadwood in a quiet corner of a garden where nobody regularly passes underneath.

It's about balancing the value of the habitat with the location and condition of the tree.

👻 So when does something spooky need investigating?

Most of the creepy-looking things you discover on a tree aren't automatically a reason to panic.

But there are some changes worth getting checked.

These can include significant new cracks or splits, substantial dead or damaged branches, sudden changes to the canopy, movement around the base or fungi appearing alongside other signs of deterioration.

Rather than assuming the worst, a professional assessment can help establish what's actually happening and whether any work is necessary.

🌳 Trees are alive with more than leaves

Trees don't just make our gardens look good.

From their roots right up into the canopy, they can provide food, shelter and habitat for an enormous variety of wildlife.

And sometimes it's the oldest, strangest and slightly spookiest-looking parts that are the most interesting.

So this Halloween, if you spot something lurking in your tree…

don't be too quick to evict it. 👻

That hollow, piece of deadwood or dark little crevice might be someone's home.

Got something strange growing or living in your tree?

Tall Tree Services provides professional tree surgery throughout Gloucester, Cheltenham, Stroud, Cirencester, the Cotswolds, Tewkesbury, Malvern, Ledbury and Ross-on-Wye.

Our NPTC-qualified arborists can assess your trees and recommend appropriate work where needed, while taking account of the wildlife and habitats they may support.

Get in touch with Tall Tree Services for a free quote.