Ridiculous statement by people who have no notion of agriculture (but claim knowledge about things like this all the same ) while even them could read this:
http://en.wikipedia.org/wiki/Arundo_donax
The Arundo Donax is officially classified as infesting crop ( wikipedia says ........” Arundo is a highly invasive plant in southwestern North American rivers”.......) and pretty difficult to get rid of ( one has to be very careful in removing it because even small bits of its rhizomes left in the soil will sprout a new plant, so by carelessly removing one plant you can actually produce more)
Which is the reason why it has spread easily (helped by the human hand that has always found a way to use it) around the world.
The plant is so invasive that it is actually used to fight off other invasive plants because it kills them all. It has a natural resistance to bugs of all kinds and growing it needs no pesticides!
It is grown abundantly (all over the world and not only in France, despite the Var country claiming they have the best varieties and largest crops, and it has been grown for thousands of years) and grows VERY quickly in every continent and its uses are way more complex than the reeds used by the shrinking number of reed instrument players (biofuel anyone?).
this is the ancient instrument called Launeddas played in Sardinia, they are made of cane and they have been used for thousands of years