Still feeling down, so I decided to go up.
But first, I went in.

What a stunning oak!
As soon as I saw that hollow, I'd jumped the little stream and climbed in. It felt like home. I wanted to stay forever.
While sitting in there, I sensed that this tree is a guardian and the word Aulus came into my mind.
The most famous Aulus was Aulus Plautius, first governor of Britain. He would have overseen this part of the country - south and east of the Fosse Way. He is described as brave but brutal.... There's also an Aulus Gellius, who was an author and who, in his one remaining work (Attic Nights) relates that the crown worn by Caesar Augustus is a famous statue was made of oak leaves because the earliest food to support life came from the oak.
Anyway.
From within, I could see a little hole on the other side.

And the end of a metal spike.

I went round the back of the tree to see if I could see these from the outside. Hole, yes; metal, no.
I did see how easy this tree would be to climb.
There's a very cool fused branch.

And the tree offers a place for dinner, too.

Further on, I saw more lovely trees.
In the roots of one, I could see.... something.
I tried to dig it out, but it was well buried. It was made of porcelain or thick glass. It could be as old as the tree!
Dad says I must return with a trowel.
Yes, follow your dad's orders 😀 ... There's a public broadcaster where I can watch streaming of almost current Digging for Britain on my laptop. Reminds me of your searches. https://en.wikipedia.org/wiki/Digging_for_Britain
You had a great visit and exploration of that oak tree. And Aulus is a worthy name.