The Prince of Wales has urged people to buy British food whenever they can to support family farms and save the countryside.
Heir to the throne Charles called on the public to harness their consumer power by shopping for home-grown produce instead of imported food.
He made the impassioned plea over "our living, breathing, working countryside" in a special birthday message he penned for this week's Country Life magazine to mark turning 67 on Saturday November 14.
The Prince wrote: "On a sufficient scale the purchasing decisions of individuals can and do change markets.
"Those of us who care enough about the grave situation facing our farmers and rural communities really can help by buying British food whenever we can.
"In doing so, we are also more likely to be getting fresh, high quality produce from a known and trusted source, offering good value for money.
"It seems to me that the key is to make it as easy as possible for people to know when they are buying British - and why that is a good choice."
Charles, who is currently on an official tour of New Zealand and Australia, features on the front cover of the magazine, pictured in an open necked shirt and jacket, resting his arm on a fence post at his Gloucestershire retreat Highgrove.
The Prince highlighted the pressure facing the country's family farms, including falling commodity prices and rising input costs, and warned that some city-dwellers may be overlooking the crucial part that farmers play in the UK.
"The rural economy is largely invisible to many people," he said. "So, it is perhaps worth spelling out, especially to those who -whether by choice or necessity - live largely urban lifestyles, that we rely on farmers to make a huge contribution to our nation's food security, environment and prosperity.
"And in all three respects, we live in an increasingly uncertain world. That is why we need to do everything we can to keep our farmers farming."
Charles stressed the important contribution small family farms make to rural communities and raised questions about industrial scale farming.
"Is it really sensible to rely on very small numbers of huge, industrial-scale farms, dairies and abattoirs?" the Prince asked.
He finished his lengthy leader with a word of warning: "This may be considered merely romantic but, to me, our living, breathing, working countryside is one of the great glories of this country. I think we should treasure it, including its people, while we still can."
Mark Hedges, editor of Country Life, welcomed the Prince's "romantic" stance.
"There's nothing wrong with having a romantic view. It's not going to be particularly romantic when it's all gone. He ends his piece with a rather worrying line 'I think we should treasure it, including its people, while we still can'," Mr Hedges said.
"The message is that if things don't change, it's going to change out of all sight."
He added: "The Prince has a powerful message where we can all make a difference. By buying British food, we will all be playing a vital part to safeguard the future of our precious countryside and everyone who works and lives in rural communities."
Mr Hedges said the Prince works hard to connect with rural communities and support farmers facing "absolute turmoil".
In 2010, Charles established his Countryside Fund, which has distributed more than £6 million in grants and emergency funding in the last five years.
Mr Hedges added: "He's the countryside champion. He's in a very special position. Unlike many people who sit in London and wonder what's happening in the countryside, he goes out and visits places. He's sees what's happening on the ground. Farming is in absolute turmoil at the moment."
:: Country Life is published on Wednesday.