Let us begin our current considerations by reviewing some of the key information presented thus far:
- Authentic crop circles, as compared to hoaxes, are defined as geometric formations of downed plants that consist of artifacts and evidence of unusual energy, such as microwave, to an extent that alters plants at a cellular level. Sometimes, however, downed plants contain such evidence yet appear to be randomly downed, or arranged in non-geometric formations.
- Primary methods of determining if a formation is authentic should include identifying evidence of unusual energy because hoaxers and artists can be very competent, creating elaborate formations within a single night. Factors such as appearance and size, no matter how initially intriguing, should be considered relatively insignificant as compared to identifying artifacts and evidence of unusual energy.
- Biophysicist William Levengood informed us that the energy waves may in and of themselves down the plants by bending the nodes. The expulsion cavities and cellular alterations, in addition to serving as evidence of authentic crop formations, may be showing us the very means by which the plants were downed.
- Crop circles began being reported in the U.S. during the 1940's. Reported crop circles hit an all time high in the U.S. in 1990 and continued to increase over the next two decades. Reports on each side of the Atlantic evolved to include unidentified aerial phenomena in the vicinity of select formations. Investigators grew to resent global governments, becoming convinced evidence was being withheld and independent researchers were being manipulated by the powers that be.
- Interesting anomalies are periodically identified that at least seem to over-arch with reports of other strange phenomena, such as the circumstances of glassy particles found within certain crop formations as well as found inside homes of select alleged alien abductees. One such Michigan abductee was involved in the 'hair curler' incident and was all but confirmed to have been in the path of very unusual energy during a reported experience of high strangeness, resulting in Levengood determining that some plant seeds along for the ride grew with “increased vigor.” Levengood stated the most unusual formation he ever saw was located in Kansas and crops within the effected area had an increased growth rate. Plants with substantially increased growth rates have also been reported in additional apparent UFO-related circumstances, such as the 75-pound cabbage produced from the garden of Lindy Tucker which was in the vicinity of downed crops and unidentified aerial phenomena. Also, the Travis Walton case includes trees located within the “ring of influence” at the site of the reported abduction growing at a reportedly “astounding” rate. 
Weapons Precedence, Vertical Mirrors and Truth-Distortion Camouflage
Long time investigator/author Dr. Jacques Vallee wrote about crop circles and their implications on his Boing Boing blog.  Vallee acknowledged that all camps agree the vast majority of formations are the work of hoaxers and artists, but additionally presented for consideration that authentic crop circles may be the work of the military intelligence community, using a beam weapon.
Vallee addressed issues such as the feasibility of such a weapon, citing that disclosures about beam weapons have already taken place.  Such devices can be airborne, capable of harming humans and can stop car engines.
Phillips Laboratory, an advanced weapons research facility located at Kirtland Air Force Base in Albuquerque, New Mexico, has long acknowledged such beams and capabilities.  A 1993 press release stated the use and direction of “high-power microwaves, high-energy advanced pulsed power and very-high-energy plasmas” had been achieved.
Researcher David Perkins further informed us that such weaponry first began being developed by the American military during World War II. Curiously, this is right about the time crop circles began being reported in the States. In his 1998 article High Heat, Perkins went on to explain how the projection of intense lasers had received military attention during the Star Wars era, including the development of numerous high-power microwave devices. Coincidentally or not, the years following these achievements included record numbers of U.S. crop circle reports.
On his blog, Vallee noted his interview with what he described as a reliable witness who observed a very curious object hovering in the sky above an area known for crop circles. The man was a professor of physics and a hang glider pilot. Vallee reported that, while doing some flying, the professor observed “something like a perfect mirror hanging vertically in mid-air.” Circling the object to determine its shape, the man decided it was cylindrical and covered with a perfectly reflective surface.
Addressing why the military would be interested in possibly using such weapons to, of all things, create crop circles, Vallee called upon his experience as a computer scientist to warn us of the potential advantages, dangerous as they may be, of effectively manipulating information and public opinion. Vallee noted the initial issue raised by the crop circle puzzle is the construction of belief systems.
He suggested that if authentic crop circles are military experiments hidden in plain sight, then the social manipulation of information providing camouflage for such experiments is indeed quite remarkable. Vallee asserted that the Internet and its promotion of myth can be used to hide a massive technological effort taking place right in front of us, and that little more than the distortion of information presented to an eager to be misinformed audience is all that is required to make such an operation a fascinating success.
The main result is to disturb genuine research of paranormal phenomena, Vallee wrote, but acknowledged this is but one potential aspect of the overall effect. Internet social patterns are most certainly an increasingly important global tool, altering public perception of both the past and future. Mastering the use of such a tool, Vallee surmised, would be well worth the effort, much less a few bent stalks of corn. He suggested, “What we have here is a remarkable example of misdirection around a stunning experiment that remains in full view of a wide public that consistently fails to ask the right questions and keeps re-asserting bogus answers.” 
Possibilities and Final Thoughts – For Now
A large percentage of crop circles are indeed hoaxes or artistic creations. Of the remaining authentically interesting formations, in which unusual energy and exploded and/or bent nodes were evident, as compared to plants which were mechanically bent and laid down, possibilities include:
- William C. “Lefty” Levengood's hypothesis that some formations may be the results of natural phenomena. Ion electron avalanches may particularly play key roles in the creation of some formations. A reasonable argument could be made that the existence of authentic non-geometric formations support this hypothesis, at least in select circumstances.
- Some kind of non-human intelligence, alien or otherwise, may be creating at least some of the formations for any number of possible reasons. Some people believe this hypothesis is supported by cases of unidentified aerial phenomena reported around crop circles.
- The military intelligence community, including its sub-contractors, may be creating at least some of the authentic crop circles for reasons that include weapons development and mastering propaganda techniques. Like the non-human intelligence hypothesis, this hypothesis is also supported by cases of unidentified aerial phenomena reported around the formations, just in this circumstance, researchers suspect the aerial phenomena is of quite human origin, rather than non-human origin. This hypothesis is additionally supported by claims of researchers being harassed and/or placed under surveillance by apparent military personnel. This hypothesis may be further supported by the existence of non-geometrically downed plants, particularly if a comprehensive study of data showed that patterns in the creation of downed plants emerged. It would be interesting to accurately identify if patterns might include authentic formations increasing in complexity over time and in ways that could be correlated with the evolution of confirmed weapons development projects.
More research and information is required to draw ultimate conclusions, and combinations of the above hypotheses are possible; they are not necessarily mutually exclusive of one another.
During this recent series of posts on crop circles, my blog received a great deal more site traffic than normal. I sincerely appreciate all of your interest.
I was particularly pleased to see my friend from yesteryear and independent ufologist, Lindy Tucker, visit the blog and register. Thank you, Lindy!
 UFO Updates: Levengood To Look At Travis' Trees
 Boing Boing: Jacques Vallee
 Our Strange Planet: High Heat
 Boing Boing: Jacques Vallee: Of Crop Circles, meme wars and web-based flypaper