I live on the coast. In front of my house are dunes covered mostly in muehlenbeckia, rushes, ferns, a few flaxes and small native shrubs.
Growing through these are some non-native grasses, a wild sweet pea and a German ivy.
These are fast-growing weeds and die down in the summer when it is dry.
However, several times a year, the council employs a contractor to spray vast areas of these dunes.
In my view, it is a fruitless exercise. The weeds always return, the natives which have been here for thousands of years, get knocked back.
The spray kills little