Have you done your annual pompom patrol on your smallholding? Now is the best time for it.
Pompom weed (Campuloclinium macrocephalum), is a flowering perennial from South America which is seriously established throughout Gauteng. It has a fluffy pink flower head and it appears in profusion in spring and summer and, when found in dense patches, it looks very pretty.
Unfortunately, pompom is a highly damaging plant, pushing out indigenous plants when it takes hold, and spreading rapidly. It is also worthless as a grazing species.
The weed is a listed invasive species (category 1b plant) in the National Environmental Management: Biodiversity Act. Landowners are therefore compelled to control pompom weed by whatever means are deemed appropriate. If you haven’t already done so, equip yourself and walk around your entire smallholding to check for this alien.
The best we can do according experts is to remove the flowers and put them in a black bag to contain the spread of the seed. It is vital that this be done again and again, as mowing will not cause the plant to die back, it will simply restrict further distribution of seeds.
Hildegard Klein of the Agricultural Research Council (ARC), stresses, “Do not burn the infestations, as this removes surrounding plants that might provide competition to the weed.” She also advises that we protect the area against fire.
In the case of single or very few pompom plants in an area, each plant can be dug up, taking care to remove at least the root crown (the area where the stem is attached to the roots) from the soil. Once the root crown has been removed, the roots should not re-grow. It is important to cause as little soil disturbance as possible, in order to prevent the mass-germination of seeds.
The selective, broadleaf herbicides picloram and metsulfuron methyl are both registered on pompom weed and will not affect veld grasses. However, do not spray after February. It is imperative that only registered, selective, broadleaf herbicides are used in grasslands.
A stem-galling thrips (Liothrips tractabilis) and a rust fungus (Puccinia eupatorii) are currently the two main biological control agents in use against pompom weed.
We also need to be proactive in terms of maintaining the natural vegetation on our plots, keeping it in a healthy, productive state, as this will also help to limit pompom invasion.