Pom pom weed is a very invasive weed in South Africa. It is common along road verges and in fallow lands but can also invade pastures and natural grazing. Once established it is very difficult to get rid of as it spreads by seed, as well as by rhizomes. The picture below is some that had invaded a lucerne field.
Pom pom weed was originally introduced as an ornamental plant, which then escaped into the wild. If people had been growing vegetables in their gardens instead of pink flowers, this would never have happened!
Sunday morning was spent with the whole family cutting off the seed heads and digging out the plants where possible, and spraying the plants with poison where the ground was too hard to dig them out. Here is a dung out plant showing the roots.
The plants are grazed by our goats, so they are not entirely useless, but they can reach a state where they push out all other plants, so I’d rather try and nip this in the bud, so to speak.