For years, crop circles have been taken as seriously as UFOs and fairies. Now, not only have the weird patterns arrived in Hollywood, but scientists are trying to solve the mystery. And the answer may lie in the soil. As the helicopter landed on the roof of New York's Rockefeller Plaza, two uniformed security guards ran out, speaking into their microphone headsets, and rushed Nancy Talbott inside. She was ushered into a suite where a sumptuous buffet was laid out. Aides made a respectful retreat as the philanthropist Laurance S Rockefeller arrived. Talbott, the president of BLT Research Team Inc, an organisation formed to investigate physical changes in plants at crop circles, had been invited to lunch to discuss an exciting proposal.
Hollywood has just given British audiences its version of what causes crop circles, in the movie Signs, with Mel Gibson playing a farming preacher who discovers a formation in his field. But Talbott had information on the real phenomenon. Preliminary research suggested the circles were made by an unknown energy.
The puzzle began six years ago for Diane Conrad, a geologist who analysed soil samples from a circle near her home in Logan, Utah. To her surprise, they displayed a characteristic generally found in sedimentary rock, caused by the pressure of tons of rock heated by the Earth's core over considerable time. Yet these samples were surface soil from within the crop circle; outside the circle, the soil showed none of these inexplicable traits. 'I couldn't understand the results,' Conrad explains. 'The soil seems to have been subjected to an intense heat of 500 to 1,500 degrees Celsius, and yet the plants were not incinerated. They were not even singed.' What kind of energy could produce heat of that intensity, yet not burn the plants to a crisp? Conrad was unable to initiate an in-depth evaluation at the time, but she passed the information on to Talbott, who has dedicated the past 10 years to co-ordinating scientific research into the circles. Research of soil samples required expensive techniques, so her mission was to persuade Rockefeller to fund it.
More than 10,000 circles have been reported around the world to date. Formations have appeared in tree tops, ice and sand as well as crops. Nobody knows how many are genuine anomalies and how many are man-made, and scientific investigation has been very limited. But Conrad's work raised questions that Talbott believed mainstream science could not ignore. After a convivial lunch, Talbott handed Rockefeller her proposal. A few weeks later, a cheque for a 'substantial amount' arrived in the post.
Field teams in the Netherlands, the United States and Canada collected soil samples. A seven-circle formation reported in September 1999 in Edmonton, Alberta, was chosen for detailed analysis. A farmer and his wife reporte seeing unexplained lights above the field about a week before the circles were discovered.
Nearly 90 soil samples, as well as controls taken from outside the circles, were sent to Dr Sampath Iyengar, a mineralogist in San Diego, California. Clay minerals in the samples were analysed using a technique called x-ray powder diffraction (XRD). X-rays are beamed into the sample at various angles, and the way they deflect provides information about how the atoms are arranged, and the kind of mineral it is.
Imagine a marble represents an atom in the mineral being examined. If you throw a handful of them on the ground, they will form a random pattern. If instead you line them up in rows, that would indicate an 'increase in crystallinity'; something has made them ordered, an as-yet-unexplained energy. This is what had happened to the surface soil from inside the crop circle.
Nothing like this had ever been seen in surface soil. 'This would normally only be found in geologic sediments exposed to low temperatures and pressures over millions of years,' says Iyengar. 'In the laboratory, temperatures in the range of 600 to 800C are usually required to achieve such crystal growth. There is no way we could explain these results. It's some kind of energy, an unknown force, that's causing this.' Talbott, excited by the results, needed the report peer-reviewed by an authority. She decided to start at the top and went to Hanover, New Hampshire, where she banged on the door of Dr Robert C Reynolds Jr of Dartmouth College. A winner of the Roebling medal for lifelong achievement in mineralogy, Reynolds is an expert in x-ray diffraction. He asked for samples to be sent to his laboratory, and performed his own experiments. The results were the same.
In a letter to Talbott, he said: '... I am convinced that the sample preparation methods and the x-ray analytical procedures used were consistent with sound, standard methods of analysis. But this brings up the question of the meaning of their results.
'Temperatures of 600 to 800 degrees Celsius are required in the laboratory for such growth and these conditions would have incinerated any plant material present. In short, I believe that our present knowledge provides no explanation...' For the crop-circle world, the involvement of such a distinguished expert in the subject is a great victory. It is the first time a scientist of his standing has taken an interest in the phenomenon. Where does the intense heat come from? Some witnesses claim to have seen small balls of light and heard trilling noises in the fields just before a circle has appeared, but whether this is related has yet to be proven. 'It is possible we are observing the effects of a new or as yet unrecognised energy source,' says Talbott in the BLT report.
One of the biggest contributions to the scientific study of crop circles has come from the Michigan biophysicist W C Levengood, who began investigating plants taken from circles in 1990. The most curious anomalies he has studies are pinhead-sized holes in plant nodes, the fibrous 'knuckle-like' protuberances found along the stem. He calls these holes 'expulsion cavities'. Levengood believes moisture inside the stems is heated rapidly and turns to steam, in some places stretching the plant fibre, and in others blowing a hole in the stem. 'It seems to be a powerful microwave energy that is causing this; it heats from the inside out. The interesting thing is, these holes occur in a matter of microseconds.'
The youngest, and most elastic, tissue in the plant stems is at the top, and it is here that he has consistently observed elongated nodes - stretched sometimes to double their normal length. Lower down, where the tissue is more fibrous and less elastic, expulsion cavities are regularly seen. These effects have never been found in control samples. Levengood also found changes to the seeds and germination capability of plants within the circles. When circles occur in mature plants with fully formed seeds, the seeds often grow up to five times faster than control seeds, and the seedlings can tolerate lack of water and light for a considerable time without apparent harm.
While investigating the crop-circle seeds at his Pinelandia Biophysical Laboratory in Grass Lake, Michigan, Levengood discovered a way of using a process he calls molecular impulse response (MIR). 'When I exposed the seeds to the MIR energy, I got the same effect as in the crop formation. We can produce seeds that grow a lot faster.' Along with his colleague John Burke, he patented the formula in 1998. Is the agricultural industry interested? 'Oh yes. We hope the grain will be ready next year. There are several companies doing big field trials at the moment.'
This summer, field researchers found expulsion cavities inside a formation resembling a celtic knot in Avebury Trusloe, Wiltshire. The formation, reported on June 2 in a barley field, was examined by the former government scientist Rodney Ashby, who began investigating crop circles six years ago. 'The stretched nodes and expulsion cavities in this formation are very interesting,' he says. 'This occurred only on the stems that were flattened to create the formation.
I always look for the most logical explanation, but in cases like this there just doesn't seem to be one.'
From the edge of the field in the waist-high barley, it is impossible to see the downed crop. The only extraordinary features seem to be the ancient Adam and Eve stones in the next field. Scholars believe they marked the beginning of an avenue of stones leading to the stone circle around Avebury. A few hundred yards inside the field, the crop suddenly flattens in swirling patterns.
Daniel Lobb, a field researcher, picks up a handful of barley stalks. Sure enough, there are tiny holes and stretched nodes that are double the length of the plants outside the circle.
Next morning at the Silent Circle, a cafe in Cherhill, the hub of crop-circle information, 15 people are watching a video of the latest circle. A map on the wall covered with pins is quickly updated with the position of the most recent formation. The cafe walls are covered with aerial photographs of the 70 circles reported so far in the UK this year, and posters by the former architect and professor of design Michael Glickman, who draws the geometry of the formations.
'Let's go,' cries Glickman. It's like a call to the hunt, and everyone piles into their cars. In the lead is Glickman, followed by the Croatian documentary maker Nikola Duper, then three Italian women, a Dutch couple who have come to Wiltshire for the past 10 years to see the circles, and us. The convoy snakes along narrow roads past thatched cottages in tiny villages. Everyone is waving and chatting excitedly on their mobiles about what the shape could be. As we pull up by the field, we see people on stepladders holding cameras attached to long poles, trying to get an aerial shot. A helicopter circles overhead and the 'croppies', as they are known, pull out cameras
Next day, when the aerial pictures are put up in the cafe, there is concern that it may be man-made. 'We're under attack,' says Glickman as he sips his coffee dejectedly. 'It's a waste of researchers' time and money to be polluting the fields with these second-rate man-made circles when there's a real phenomenon needing more studies.'
Interest in the circles has intensified this year. Signs opened in the US on August 2 and took more than $60m in its first three days, sending it straight to No 1 at the US box office. The British drama A Place to Stay, set in the crop circles of Wiltshire, also looks set to pique public interest.
Freddy Silva, the British author of the recent book Secrets in the Fields, which sold 10,000 copies in the US in its first week, is looking over a formation at the Gallops, near Beckhampton, an impressive shape with 76 radiating spokes. A deer leaps to the centre and stays for a few moments before running out. 'Whatever Hollywood comes up with about the theories behind the crop circles, it will never be as intriguing and mysterious as the real thing,' says Silva.