Fans of foraged food, from mushrooms to sweet chestnuts, are being warned against flouting a ban on taking wild produce from the Royal Parks.

The number of incidents of foraging, which is prohibited in London’s Royal Parks, have “mushroomed”, with 35 police warnings issued last year in a 600% increase on the previous year.

One picker even ended up in court after ignoring a police caution and coming back for more wild ingredients, the Royal Parks said.

Autumn Stock
Mushrooms are a big draw for foragers (Anthony Delvin/PA)

While foraged food is increasingly popular for people, the charity which manages some of London’s most famous green spaces is concerned that it is depleting vital food sources for wildlife and could damage nature in the parks.

Of particular concern is the removal of sweet chestnuts from Richmond and Bushy Parks, which are home to roaming deer herds.

After the breeding season, exhausted and lean deer gorge on the harvest of chestnuts and conkers to put on weight again to help them survive the winter.

October and November are peak time for mushrooms, which can provide important food for animals in the park and a habitat for many bugs.

Picking mushrooms, which are the fruit of underground fungi, can hinder reproduction and harm their ability to thrive.

That has knock-on effects for wider wildlife as fungi helps dead plants decompose and recycle the nutrients so they are available for living plants – particularly important in nutrient-poor soil habitats found in some of the parks.

Julia Balfour, head of ecology for The Royal Parks charity, said: “This sharp increase in the number of people removing nuts and fungi is extremely concerning.

“Many people enjoy foraging in hedgerows and woodland at this time of year, but please don’t extend this to our parks.

“Protecting wildlife and the biodiversity of our busy parkland is an ongoing challenge for The Royal Parks, and we need the public to work with us on this.”