The National Trust is stopping using plastic in its membership cards, saving 12.5 tonnes of plastic a year - almost the weight of two African elephants.
As well as making the cards from super-strength paper the charity is also offering plant-based plates and cups, potato starch magazine covers and reusable plant pots.
From next month it will become the UK’s largest membership organisation to ditch plastic from its cards - which it says will help mark its 125th anniversary
The change is thought to be the first time in the UK that the new, entirely recyclable and compostable material is being used for a membership card on such a large scale.
The new card will be made from a special type of strong and durable paper, and features a tough water-based coating.
The paper is certified by the Forest Stewardship Council - an international organisation dedicated to promoting responsible management of the world’s forests.
"The majority said that of the trust’s actions to tackle climate change, reducing single-use plastics was their top priority."
They are also produced in a mill which is powered by its own biomass.
As well as being a fraction of the price to produce, the new ‘paper’ card will replace the old one which was made from plastic and chalk – a byproduct of the mining industry.
Reducing the charity’s impact on the environment is high on the agenda for thousands of the trust’s supporters.
A recent survey showed that more than half of National Trust members are prepared to make lifestyle changes to benefit the environment, and the majority said that of the trust’s actions to tackle climate change, reducing single-use plastics was their top priority.
Mel Nursaw, from the trust’s membership team, said: “Replacing our membership cards is a great step towards helping to reduce our impact on the environment, which we know is an important issue for so many of our supporters.”
This latest move by Europe’s largest conservation charity is part of a range of measures to protect the natural environment and tackle the climate change crisis.
In a speech Director General Hilary McGrady said the charity had a 'responsibility to do everything we can to fight climate change, which poses the biggest threat to the places, nature and collections we care for.
They added: "This is just one step in the charity’s efforts to remove plastic; it has already committed to phasing out selling single use plastics, and is currently exploring how to transfer its physical cards to digital ones."
Initiatives already undertaken include replacing food and drink packaging with compostable, plant-based materials, introducing a discount on hot drinks for bringing your own cup, offering free water to reduce plastic bottle use, moving to reusable plant pots and trays at its nurseries, and switching the wrapping on 4.5 million members’ magazines from plastic to potato starch.
As well as being better for the environment, the new membership card can be composted or thrown away with paper as part of regular household recycling.
Other areas on the trust’s plastic hit list include removing plastic from most of its greetings cards and wrapping paper, looking at alternatives to plastic tree guards, trailing cordial drink dispensers to reduce the sale of bottled drinks; and working with suppliers on more sustainable packaging for shipping.
Lizzy Carlyle, Head of Environmental Practices at the National Trust, said: “As an organisation committed to creating and maintaining a healthy and more beautiful natural environment, we are determined to use every opportunity to minimise our use of non-renewable resources, and cut down our waste.
“We have taken a number of significant steps to make improvements, but with an organisation the size of the National Trust it isn’t always something that happens overnight.
"We know there is much more we can do, and taking steps like replacing our five million membership cards will significantly help us protect our environment.”
The new cards will begin arriving with membership renewals from March.