My Year of Darwin 3/23/2014: Killer thistle!

"The clumps were the most brilliant green, and they made a pleasing miniature-likeness of broken forest land, When the thistles are full grown, the great beds are impenetrable, except by a few tracks, as intricate as those in a labyrinth. These are only known to robbers, who at this season inhabit them, and sally forth at night to rob and cut throats with impunity" -Charles Darwin, Voyage of the Beagle  

Not only does giant thistle make land unusable as pasture, it is used as a liar for those that would do harm. Reminds me of the stories I heard about the areas around New York City and New Jersey at the mouth of the Hudson. Now these areas are a sea of phragmites (common reed) but it was covered in white cedar. Not only is white cedar a superior wood (rot resistant) but the white cedar forests harbored pirates that would harass ships coming into New Amsterdam.