On one of our Toby-walking routes is a small area of 'bush wilderness' in a triangle area inside a now unused railway junction. Ironically, this area of random-looking native plants and grasses is of course entirely artificial, put in as part of a local landscaping effort no doubt. It even contains a dry creek bed with a wooden bridge, well above any watershed, where water has never run...
And every month or so there is a rash of blue-green splotches (visible at the bottom, in the picture above). This is the poison put down by the local council to nail all the non-native (exotic) grass that refuses to take a hint and works hard on moving in and re-colonising the area.
It's rather ironic that the most heavily maintained part of the local landscape is the bit that's meant to look like the local untamed, untouched wilderness.