Help eradicate the Parthenium weed

Namibia still has infestations of Parthenium hysterophorus and farmers are urged to help eradicate it while there is still a window to do so. The weed is widely regarded by researchers as one of the most damaging invasive species in Africa.

The National Botanical Research Institute (NBRI) is working to address this threat and needs farmers and landowners to report all known locations of the weed.

Where mature seeds have already dropped to the ground, serious spread can be expected once the next rainy season begins. Field observations include:

• In Windhoek, flowering plants were collected and burnt where possible, but the ground remains seeded with mature seed.

• Burning young plants was tested, but dew and the plant's taproot allowed young plants to recover.

• In a seed-watering test, mature seeds were sown and watering was stopped on half the sample after two weeks. All the seedlings deprived of water died. This suggests that, in the field, deliberately forcing germination through watering and then allowing drought and frost to finish the job could be an effective control method, but this would need to happen soon to make use of the coming dry and cold conditions.

Please report any known parthenium locations to Gunhild Voigts ([email protected]) and take action to control the weed where you can. Early, coordinated reporting will help NBRI target eradication efforts before the next germination cycle.

Let's join hands to protect our habitat.