Vegetation on Mars?

I knew there were some claims that vegetation exists on Mars on the basis of real authentic pictures(no sarcasm) like this and this, but I was always sure that the people who say this are the same wackos who claim that Galileo will cause a huge nuclear chain reaction on Jupiter when it crashes into it in couple days.

So it’s just another crazy conspiracy theory, and everything is nice and pretty until… look what I find on :

Clarke? Is this serious? Can those “stuff” in the pics really be some trees or fungus or whatnot?

NASA says itssand dunes.

My question: back in the 1950’s , sevearl prominent astronomers were convinced that Mars had vegetation-I remember seein photograps of mars 9made by the 200’ Mt. Palomar reflector), showing blue-grren areas on the planet. Why were these pictures showing a blue-green color? Was it the film used back then?