Humans record and categorize all known crop formations, and the alien races put them right where we can find them for that very purpose.
"Special interest groups" create many additional formations though, for the purpose of muting and confusing public opinion of all formations, authorship and meanings.
It's a big game of competition between the human circle makers, but to the professionals behind them it's a serious business of preserving the current corrupt way of governing Earth.
Authentic crop formations spell out important things we need to know about the alien races and their activities here.
The fact that humans cannot reproduce them with the same affects on soil and vegetation further testifies (along with personal claims of contact and public sightings of crafts) that alien life is visiting.
The fact that the formations are so coded that we cannot read them or further speak for (misrepresent) the messages testifies to which are authentic and which are fake.
The greatest value of the messages to us from the alien races will be in our historical perspective, because when we solve or are given the codes, and we can read back over the history of alien visitation, only the truth will come out at the end of all these years of government-generated confusion.
The long history will prove the alien races' abilities and intentions, including their peaceful visitation and continuous offer of assistance despite the accusations.
The reasons for government corruption and cover-up of alien visitation to our world over this period of time will also become openly apparent to the public.
Crop Circle Codes
What the alien races want to accomplish is giving humans true information about themselves.
If we (our leaders) already, today, had the codes cracked, they could make more formations that "prove" more untruths.
If we could similarly affect the molecules of the stems, we would not recognize authentic from fake.
The alien races only want to help our whole race, not interfere between our factions.
It would be greatly beneficial to all of us if our governments would change their ways before they have to face the music.
Only the publics can force the changes upon our governments.
It is not the place of the other races to do so.
Fake Crop Circles
The recent crop circle found in a field in California is human-made.
Our alien visitors are responsible for some of the crop circles, the largest percentage among the earliest reported.
A few different alien races have created them.
The purpose of the authentic ones made by alien life is to bring some truths to humans on Earth.
They are displayed openly so that any human may witness and preserve them.
The messages are coded to protect what they say.
Nobody on Earth has the codes yet.
The purpose of the fake ones made by humans is to claim authorship and otherwise discredit the authentic ones.
The confusion is all that is necessary to keep humanity ignorant of the truth, for now, and at the mercy of our world leaders.
When it is time, and as safe as possible, we will read what the messages say, and we will have an unadulterated written history of the truth.
Think of the formations as a personal coded diary of information and events published for the public daily by the suspects, that cannot be deciphered (or hidden, or rewritten, or appended, or edited, or censored) until it's time for closing arguments of their 50 year criminal trial.