Day 122/17. Another mystery in the garden.

We have an old impressive English Oak in our garden. Probably pushing 100ft high and clearly older than me......
In the last few days we have noticed that the new buds have been dropping off the tree. Fearful of some horrible disease or recent frost damage we looked at the buds and new growth and all looks normal. The leaves are not withered or dying, it just looks like the new growth is falling off.
But what could be causing the new growth to fall off like this? There must be hundreds of the new twigs scattered over our lawn?
Well, tonight we figured out what was causing this damage to our mighty Oak.
Tomorrow all be be revealed as I will try to get a picture of the culprits.