This plant is from Mexico originally and in South Africa has become an invasive plant categorised as Category 2. This means that it may only be grown with a permit and is not permistted to be planted within 30m of watercourses, dams and floodplains.
This plant ideally should be removed when very small. When this plant grows to its full size it is very hard work to dig it out. It has sharp tips and has very tough sword-shaped leaves. It grows a very long centre stem with a large greenish flower. It propagates itself via small plants.
In order to poison this plant, the leaves have to be cut off to gain access to the centre of the plant – then the centre is cut out and MSMA [Monosodium methyl arsenate] poured into it to kill the plant.
A photograph of sisal used on a pavement in Cliff road was sent to me by a reader. This should by law be eradicated as described above.