Hay olly, maybeso the name of the smell of fresly cut grass is "HELP".
Some Germans found that grass when cut shouted a smell that attracted bug-eating bugs to come and eat the bugs that the grass thought was eating them.

And there is this from the Net:

The chemistry in pleasant odours - such as newly cropped grass - is so powerful, their scents can alter gene expression in the brain and reduce aggression, according to a neuroscientist.

Dr Judith Reinhard's team at the Queensland Brain Institute at the University of Queensland is working to uncover the molecular mechanisms behind the phenomenon of aromatherapy, which has long been used to calm the nerves and sharpen the mind, the Telegraph reported.