Vernonanthura phosphorica 'Invading Zimbabwe from the East'

Sometime in April 2017, I was in the Eastern Highlands of Zimbabwe, in Chipinge where some of the biggest tea estates and macadamia plantations are located. I was surprised to note that there is the plant which doesn't look native which is spreading and invading almost everywhere. So I asked around at one of the estates, Clearwater Estate. One senior manager told me that the plant is believed to have been introduced by people who wanted to attract pollinators to their macadamia plants owing to its bright flowers. I tried looking around for the name but in vain. They suspected it has originated from China. That's all I got then.

A few months later, I went to Chimanimani about 60 km from Chipinge but still in the Eastern Highlands. The same plant has invaded, again. This time was flowering. And yes, the flowering season is synchronised to the macadamia flowering season, somehow giving credence to the suggested reason for the initial introduction. I asked around again. This time they said the plant literally 'arrived with Cyclone Elin of 2000'. The locals in the area call it 'ChimuCyclone' - The Cyclone Plant. But others concur with their Chipinge counterparts that the plant was brought by some beekeepers to attract bees and boost their apiculture business. 

Vernonanthura polyanthes in flowers

It seems nobody really knows how it came to Zimbabwe after all but it is invading the Eastern Highlands which is characterised by high rainfall and high altitude. The impacts are very devastating. It's encroaching farmland and forestry areas and it is 'succeeding' native vegetation. Where I have observed, it seems there is limited undergrowth in the areas where the planted has invaded. This is probably because it has a huge canopy which limits light penetration. It might also be a result of nutrient depletion because the plant reproduces prolifically. 

I also heard an interesting tale from a forester at Border Timbers Company. He said whenever they cut it down, it regenerates with many shoots which form a bush. The other thing was that whenever they apply herbicides like Roundup, the plant produces some 'liquid stuff' before growing again. Does it have some kind of chemical defence against chemicals? I found it very strange but intriguing. But that's all I got from him. No researches have been done to confirm or even dispute that.

Now the flowers that people were saying they are 'bright' coloured. Well, they are not that bright which made me think maybe there is something to do with the composition and qualities of the nectar which attracts pollinators - in case the pollinators hypothesis is correct. 

I tried looking around for literature on the plant. There is nothing much except that it's native to Brazil and its name is actually Vernonanthura phosphorica, not ChimuCyclone. A few months later I learnt the name has changed to Vernonanthura polyanthes and Bvumba - near Mutare - is its next colony. The rate at which the plant is colonising the Eastern Highlands is alarming. It requires a collective effort involving the Environmental Management Agency, Agro-industries like Ariston Holdings,Tanganda, Border Timbers, academic institutions in the area like Africa University and Manicaland State University of Applied Sciences, and the community to deal with it as a matter of urgency. If we blink then we lose it. Before thinking about it, it will be all over the country and we will surely lose the battle. Let's not wait until we have another Lantana camara. We need to think of integrated management systems involving physical, chemical and biological methods now. Researches should be done on natural enemies and possible treatment options.