Foragers fear blackberry picking could be outlawed under "vague" new by-laws being proposed in one city.
Bristol City Council wants to introduce new rules for its parks, including a ban on the removal of "the whole or any part of any plant, shrub or tree".
Andy Hamilton, who runs foraging walks, said the new by-law was "too vague" and if the "letter of the law" was followed it would make foraging illegal.
The council insists it is not trying to ban activities like blackberry picking.
More than 3,000 complaints about "nuisance in parks" were received by the authority and police between 2011 and 2013.
Mr Hamilton said: "The council may have the best intentions but once this law is in place it's going to be very difficult to get it rescinded.
"I can't believe it's really that much of a problem," he said.
"People have been picking the land for centuries and foragers know that damaging plants will mean that next year there won't be anything to forage.
But a council spokeswoman said the by-law in question was "only intended to protect plants (and other things) from damage".
"We will obviously take a common sense approach and these by-laws are absolutely not designed to stop people enjoying our parks and green spaces," she said.
"We have no intention of preventing responsible people from making good use of our natural resources, as long as they are not causing any damage."
A consultation into the proposed new by-laws is due to end on 20 March.