German Empire - 5pfg Green+black

Good Evening
Hope yor are well.

In the 60's I received many stamps from an uncle, among them are some sheets like the one I'm posting.
My main question is that I could not identify the green + black 5Pfg stamp .... Can anyone clarify for me?

For now, ok, I would also like to know the best way to remove the stamps from the leaves without damaging them, if I decide to remove some of it.

Thanks in advance.

Wagner
Thanks in advance.

It's the standard issue overprinted with black edges as a memorial to Hindenburg after his death.

For all but the couple of mint stamps at the bottom, put the page in water and let the stamoos soak off.

Hindenburg memorial issue, six values overprinted, Scott 436-441 from 1934.

Very grateful for the answers.
GeoffHa very interesting your explanation.
John Becker thanks for the guidelines.

GeoffHa, so, what to do with the couple of mint stamps at the bottom ?

Remove very gently from the paper - paper away from stamp, rather than stamp away from paper. If they're stuck down, you'll have to soak those too. Not too much angst, as they're common stamps!