Pompom Weed Invasion

The Smallholder magazine has been writing about the highly invasive Pompom Weed for many years, yet some people still do not appreciate the seriousness of the infestation of the plant throughout Gauteng.
Pom-pom weed (Campuloclinium macrocephalum), has a fluffy pink flower head, and appears in profusion in spring and summer and, when found in dense patches, makes an eye-catching sight.
Despite its pretty colouring, pom-pom weed is a highly damaging plant,pushing out indigenous plants when it takes hold, and spreading rapidly. It is also worthless as a grazing species.
Spread of the plant can be limited by cutting stems right back to prevent seed production. Further control can be achieved by a combination of mowing, burning and minimum tillage to encourage grass over-seeding the invader.
Three herbicides are currently registered for use on pompom weed: Brush-Off, Access 240 and Climax, metsulfuron methyl.
In general, physical methods of control, such as uprooting or hoeing, are ineffective and make the problem worse through disturbance. It is not advisable to plough lands with pompom weed as this will damage the rootstock, stimulating further vegetative growth and denser stands.
Spread of the plant can be limited by preventing seed production. Aerial stems can be cut right back before the flowers produce seed. However, be warned that the plants will be stimulated to produce more stems and in order for this method to work the plants will have to be cut back several times until the end of the growing season.
Repeated cutting back of aerial growth should deplete nutrients stored in the roots, weaken the plant and limit seed production. This method however is only practical on a small scale. It is advisable to remove all flower heads from the site, being careful not to spread the weed further, and dispose by burning.
In terms of biocontrol methods, the Agricultural Research Council has released Liothrips tractabilis in various locations throughout the province. However, biocontrol measures will not eradicate the plant and will only help to reduce the spread.