At last it is August, time to leave the tribulations, trials and triumphs of sustainability and think about something completely different for a change. Crop circles, perhaps? I first encountered crop circles one summer evening, driving across Salisbury Plain on the A303. As I approached Stonehenge (tut tut, millions spent, still nothing done), I noticed on the opposite side of the road a large number of parked cars and a sizeable gathering of people in a wheat field nearby.
Curious, I did a U-turn, found I had to pay £3 to park, and then ended up among a herd of independent-minded souls who had spurned the eternal mystery of Stonehenge in favour of the electrifying phenomenon of 151 short-life circular recesses of different diameters formed in standing wheat. The full extent of this intervention in the landscape was difficult to really assimilate from ground level - only the nearest circles could be reached on foot - but, luckily, there was a crop circle enthusiast present to sell photocopied plans of the whole pattern (300m end to end), showing its exact layout and orientation.
Apparently this crop circle had been created early one evening a few days before. The photocopy vendor advised me that there was 'evidence'- a pilot had flown over the site at 17.30 and seen nothing, only to be amazed on his return by the sight of the whole scorpion-shaped creation, complete and perfect, without a guilty person in sight. The pilot had quickly reported his find; the farmer had opened a temporary car park, and crop circle researchers had put it on the Internet. Within hours the site was in business. The only unanswered question, apart from how to get up high enough to see the whole thing properly without hiring a helicopter, was what did it all mean?
Crop circles have been manifest in England since the 1970s and in recent years have appeared in other countries as well. As yet there seems to be only one explanation as to why they did not appear or were not noticed before that date and that explanation involves extra-terrestrials, abductees and the Roswell incident. Anyone who recoils from that kind of wild brainwork is on their own, faced with the need to come up with a credible alternative, which is easier said than done. It may be obvious why canny farmers demand cash for parking in nearby fields; why circle enthusiasts copyright their survey drawings and aerial photographs and publish magazines, calendars and books; even why British Gas has launched an advertising campaign based on a digital image of a crop circle in the shape of a radiator. But when it comes to making the circles themselves, no one knows.
The obvious explanations are no good. Tractors would leave tracks behind them and so would people. Cranes are impractical and the patterns are too elaborate to be done quickly or in the dark. The geometry of the compositions is always precise, even though the materials are wheat, barley or oilseed rape. The circles are always perfect circles, the spirals perfect spirals. The flattened spaces inside the circles are always floored with stalks that are bent and not broken.
The wise among the crop circlers understand that unsolved mystery is better for their cause than any explanation could ever be. As Michael Glickman writes in the second edition of his invaluable handbook, Crop Circles (Wooden Books, £6.99): 'A visit to a crop circle, the direct personal experience of its magical and complex architectural space, must be one of the most extraordinary experiences the world has to offer. Real understanding of these events can come only through a contemplation of their shape, their design and their geometry.'