As the shop keeper owner with the tallest ladder it’s my job to put the banner up. The branch that we hang the banner from is a bloody long way up.
Ideally I’d like to hammer some pitons into the tree ,will that harm it? It’s about 2 feet thick.
Then is there a gubbins so that I don’t have to tie a knot? It always goes a bit slack after tying.
I’m thinking some sort of crocodile clip that the rope is pulled through with teeth that grip it. Then you’d just pull the jaws apart to release the rope.

you insured?

Put a longer rope on it. Throw the rope up n over the branch. Tie off at ground level !!

Zip ties attached to screwed in eye hooks?

fancy pants dinghy cleats

Don’t do that. Put a climbing sling or two round the tree
https://www.decathlon.co.uk/C-33079-climbing/N-246823-product-type~sling

ratchet tie-down straps
http://www.screwfix.com/c/auto-cleaning/ratchet-straps-lashing/cat810012

Sky hooks?

Then is there a gubbins so that I don’t have to tie a knot?

Google round turn and 2 half hitches. It’s way easier then messing around with ratchet straps.

Have 2 sets of lines on the banner, 2 long ones so the people on the ground can pull on to lift the banner, then 2 shorter ones to tie off around the branch.

As a forester that formerly worked in event infrastructure, that sounds a terrible idea.

You’re going to need slings, paracord, bungee cord and zip ties.

What’s the thoughts on screwing something permanent into the tree?
This is what we have.

Do away with the banner and get one of those inflatable balloon men things.

What’s the thoughts on screwing something permanent into the tree?

see above.

You don’t gotta screw into the tree. There are many ways of fixing around trees without harming them.

Do you own the trees anyway like?

As for screwing into a tree ..we have a tree that has grown around a chain link fence without any ill effect.
How does that differ to screwing an inch into the bark?

As for screwing into a tree ..we have a tree that has grown around a chain link fence without any ill effect.

Apparently if you leave a bridle on a horse long enough it can also grow it’s flesh around it.* Not sure it’s without ill effect.

Besides you don’t own them.

*The Archers is very educational.