WITH last year's 50th anniversary of the Yorkshire Dales National Park now a fading memory, perhaps it is safe to raise a treacherous thought: Britain's national parks have had a malign influence on our countryside.

Enemies of the national parks, of which there are many, will be keenly anticipating a demolition job on the parks, often accused of "dead-hand" planning and indifference to local needs.

They won't get one.

The landscapes of our national parks might have been created long before the national park label was attached to them. But without the national park guardianship of the last half century, they would be far less beautiful than they are.

A drive up the A65 along the western boundary of the Dales is instructive. Outside the park, business signs are more prevalent and prominent. They erode the unspoilt character of the landscape which park policies, including careful control of roadside clutter, have done much to protect.

A source of greater friction, the virtual ban on barn conversions except in or near villages, has the same crucial aim. Conversions in open countryside would rapidly suburbanise the landscape.

Yet, in recent years, the parks, whose original brief was confined to protecting and enhancing the landscape, have expanded their role into community support. Coupled with its new locals-only policy for new homes, the Dales' park authority is exploring further ways to provide affordable homes. Meanwhile, community grants have saved or refurbished many village halls.

Over in the North York Moors, a Farm and Rural Community Scheme has produced benefits ranging from environmental work by a "village caretaker", who served several communities in the Esk Valley, to the promotion of local products, including food, furniture, clothing, sculpture and pottery. The Moorsbus service is as valued by locals as by visitors. And, post foot-and-mouth, there are payments to help shepherds who need to gather their flocks over a much wider area.

So where is the downside of the national parks? It comes through fostering the notion that any countryside that doesn't enjoy a special status, be it national park, area of outstanding natural beauty, site of special scientific interest, or nature reserve, is fair game for anything that a developer might choose to throw at it.

Wind farms threaten to plant themselves on any high or exposed ground lacking "landscape" protection. Elsewhere, Britain's countryside is under an astonishing assault, from homes, retail parks, industrial estates, transmission lines. Current examples in D&S Times country include the intended 30-acre expansion of Teesside (sorry Durham and Tees Valley) Airport; a proposed motorway service station at Kirby Hill, near Borougbridge; and, a double whammy down Borougbridge way, an addition to the giant cold stores that some years ago sprang up on the wrong (i.e. west) side of the A1 near Roecliffe.

All this is on top of eyesores like Thirsk Industrial Park, which has wrecked the only open-country approach to the town, and the recent rape of the Vale of York by a second line of gigantic pylons.

On his journeys to prepare his book, England's Thousand Best Churches, published in 1999, Simon Jenkins was struck by what he called "the virtual collapse of town and country planning in the latter part of the 20th century".

He observed: "Time and again I found local people apologising for some outrage inflicted on their village or town ... as if theirs was a unique misfortune. They were genuinely shocked to find that their experience was universal."

Jenkins returned to this theme in his companion volume, England's Thousand Best Houses. Noting how development had been allowed to "mar the setting of the most beautiful places," he concluded: "The traditional English landscape has never been more comprehensively threatened as now." Everyone who uses their eyes must agree with him.

Does it matter? Yes, for the countryside seen most often by most people is not our national parks or AONBs. Far more extensive, it is the land in between these showpieces. As the fierce protests generated by developments mentioned above demonstrate, this "ordinary" countryside means much to local people.

It is an everyday foil to urban stress, and if we awake one morning to find we need to travel to national parks to obtain this sanity-retaining balm, we will be in serious trouble indeed.

Viewing the contemporary sprawl that he judged to be more damaging than the ribbon development of the 1920s and 1930s, Jenkins feared some "ghastly mistake" had been made. Arguably the mistake has been to put an aesthetic, or "conservation", value on only the most attractive or ecologically significant landscapes.

On our small island, the whole of our countryside now needs the kind of protection hitherto thought appropriate only for national parks and other "special" landscapes. The parks should be regarded as a template for the wider countryside.

Ridiculous? Revolutionary? Not as much as it might seem. For with food production no longer the sole driving force of British agriculture, farming policy has already shifted towards conservation. Drawing on the national park experience gained over the past 50 years, that shift needs to go much further.

Long before the destruction of our countryside provoked Jenkins to near-despair, the alarm was sounded by John Betjeman. He foresaw the disappearance of the English countryside back in 1963.

In an essay lamenting the urbanisation of Middlesex, he observed: "This is what every county in southern England and a good many in the North and Midlands will soon become. Probably there is no turning back, and for that reason every acre where there is still quiet and the smell of grass and the sound of brooks becomes more precious and essential for our recreation."

"Every acre", you will note. But the Campaign to Protect Rural England has calculated that between 1980 and 2000, a higher proportion of open land was lost to development than in any previous period of the 20th century.

Currently there is talk of extending the Dales National Park to include the Howgill Fells near Sedbergh. That's small beer. Our national parks must march confidently forward to colonise the unglamorous, often abused, but still greatly treasured rest of rural England.

Nothing less will save it