I remember when I was a teenager reading about oak gall ink in a book on art techniques but I hadn't tried it until today.
Oak galls are fascinating little discoveries in themselves. Found on the underside of oak leaves the are created when a teeny parasitic gall wasp lays an egg on the leaf bud. The interaction between the leaf and the egg as they grow creates a gall, a little ball in which the wasp larvae can grow and eventually it burrows out and flies free.
The wasps emerge in the autumn leaving the galls behind. Last week, I picked one off the forest floor and as I was chatting with someone about what it was I gave it a squeeze and brown water came out.
There are lots of recipes available on-line which involve grinding oak apples and adding iron but this water, just freshly squeezed, made me wonder if this would work as an ink. The oak is really high in tannins and it stains really well.
I got a feather and snipped it into a quill and it worked perfectly. Instant ink to be harvested from the woods.