UPDATE 16 June 2014
These days we know we have genes that do not work no more. They are there in our genome but have no function anymore. In a number of cases we found the same gene well working in animals and we were able to precisely point at the defect in the human gene why it doesn't work in us no more. That's how nature works.
Maybe it is the same with brain parts. Maybe we have some brain parts that are there but inoperative, inactivated, maybe with errors too. In the course of millions of years those brain parts and the genes that steer their growth, are slowly decaying, diminishing and finally disappearing.
I guess the experiences in the crop circles are the reactivation of such an ancient brain part. But mind, suggesting is something, proving is different thing. I am afraid we have to wait 100 up to 200 years until we are able to create the nanostructures with which we can see what precisely is happening there in the brain; see page 1 of the storyline EXISTENCE (orange line of buttons). If we succeed - IF we succeed - to create these nanostructures, THEN we might find some treasures right in our skull.
UPDATE 27 March 2014
Janet Ossebaard's Circularsite has changed, the content is renewed. In an article dated 17 august 2013 in the old content she wrote about the nowadays weal and woe of the English Wiltshire crop circles.
In wintertime preceding 2013 the farmers met in a gathering. They decided to mow out all circles immediately to discourage the phenomenon and reduce number of visitors.
Monique Klinkenbergh founded The Crop Cicle Information & Coordination Center, talked with the farmers, gave them 500 pound per formation if they would leave it until harvest and involved the Wiltshire Police, the Farmers Union, the Tourist Board and the Devizes Museum.
The book of Janet Ossebaard “The proof”, page 66 up to 89, describes quite a number of changes caused in the human body and mind when in the crop circle.
Apparently the farmers don't feel these changes.
Apparently they don't visit the crop circles.
They think the phenomenon can be discouraged.
There are people with similar mental abilities to change the human body and mind. They recognize the changes crop circles can make in humans. They must be attracted by the phenomenon more than other people.
Before the phenomenon took off, say before 1980, there already were circles in the fields of Wiltshire. Nature creates crop circles - that's already one circle maker in Wiltshire. But they were round and there were little.
In rural tales the low hillside landscape of Wiltshire is known for their strange mental effects for long. Apparently crop circles amplify these effects.
Personally I take into account the crop circle patterns are designed by humans and e.g. the patterns are put into the soil in wintertime by humans.
If so, then it must be a secret group of people. The experiences in the crop circles must have given them the strength to keep this a secret for so long a time. The experiences in the crop circles. So the circle makers are amongst the visitors.
As said, the farmers don't visit the circles. So the farmers are not the circle makers. But if they did visit the circles, they might meet the circle makers.
As suggested, some of the circle makers have unusual strong mental powers. I advise the farmers night surveillance by silent drone. It must be possible to supply some drones by glide wings so they can shut off the engine and glide silently over the fields long enough to pass over them. Somehow one should combine the design of a small glider with that of a drone. During vertical drone flight the wings should be able to rotate into vertical position along the red axes, see the picture. I guess the wings best are allowed to move freely until transition to horizontal flight..
It seems unlikely most of the circles are downed by the hand of men. There are not enough photographs, films or reports of groups caught by surprise while halfway down making their circle.
To me it seems most probable a natural force downs the crop. I take into account people steer this force by methods unknown to nowadays physics yet.
Strange the Eltjo Haselhoff measurements have never been repeated.