was thinking about this myself, sadly the nanny state we live in prevents anyone from doing this sort of stuff without adequate public liability insurance, risk assessments and compliance with the HSE regs around equipment
the only way i can see to avoid stuff like that, is for us never to become a formal "group" or club. for any tools we "choose" to use in our "individual enjoyment" of the woods (albeit whilst amongst friends) and none of us ever ask another to do something...
if each of us just happened to be in the woods, just happened to have gloves and bags and a folding saw and just happened to decide as individuals to pick up that piece of rubbish or clear that branch sticking out across the footpath.... we might just maintain the activities as individual responsibilities
but, i still wouldn't be 100% that the trust would still be absolved of responsibility if they gave permission and someone got hurt and decided to "claim through injury lawyers r us" (translates as vampires of society). not saying any of us would, but you never know and they are public woods that others may be in and could get injured.
disclaimers are not worth paper they are written on in law sadly
of course, if the trust were to explicitly say to us "do not clear that fallen tree 'there', 'there', 'there', 'there' and 'there'........ and what ever you do do not pick up any rubbish when you spend the night in those woods.
then they would be absolved of any liability which would then be firmly in our laps as individuals (as we are not a club)
woods would look nice and clean of litter though
