Jay Goldner, who did the superb translation of Sacred Geometry Design Sourcebook from English into German (Mandalas Der Heiligen Geometrie), has a website devoted to the amazing cereal glyphs (a.k.a. crop circles) that appear predominantly in the UK and Europe, but evidently have been around for decades all over the world.
Despite the fact that many have been hoaxed, there is also ample evidence to suggest that many are not of human origin. My wife & I walked through a formation in the UK in the summer of 1998 that showed remarkable weaving (alternating stalks); if this was hoaxed, someone went to enormous effort! Among many other unexplained discoveries, Nancy Talbott and her colleague William Levengood of BLT Research Team, Inc. have showed changes in the magnetic fields of countless plant specimens carefully selected and analyzed relative to their coordinates from a fixed reference point. There are significant magnetic changes to both the downed crop (which is noticeably different from stalks that are intentionally bent over or snapped) AND the unaffected (standing) crop.
BTW, Mandalas Der Heiligen Geometrie is currently out of print by the German publisher, which we’re working on remedying. Meanwhile, I have several copies available for customers in the US, or elsewhere with adequate postage.
Here’s an example of his artistry using the geometry of crop circles as inspiration.