Now here is a plant that looks like a nice ornamental plant to have in your garden. Many people would agree as they have accidentally purchased it in recent times (mainly early 2008) from a local nursery or a chain store.
Unfortunately though it is not what it seems. Rather than being one of the plants it was (inadvertently) labeled as (usually Stipa capriccio but see an extended list below) it is actually the imported Mexican Feather Grass (Nassella tenuissima).
The stealthy spread of the plant is illustrated by the story of an off-duty Queensland biosecurity officer - he discovered the exotic weed in street landscaping in Oxford Street ( a trendy cafe strip) in Bulimba, Brisbane.

Why is Mexican Feather Grass a problem?
It is hardy and drought tolerant (so far so good) but it is also very difficult to control. It will replace native and other grasses. It is unpalatable to stock and is a low protein plant. The plant is closely related to serrated tussock which is probably Australia's worst pasture weed. It is believed, therefore, that it has the potential to invade a greater area than serrated tussock.This is a Class 1 pest which has the potential to readily spread over millions of hectares. It has no grazing value and would make our pasture land virtually worthless.