WHAT IS THIS SCOURGE OF PINK FLOWERS?
Edited with permission from Mercia Komen of the Crocodile River Reserve. Mercia has headed a team of environmentally conscious residents the neighbouring
Crocodile River area, and has made an enormous difference to curtailing the spread of Pom Pom weed and Wild Verbena in this area. She agreed to share this
information with the Chartwell Conservancy in the interests of assisting us to join in the drive to remove these invasive weeds.
oooOOOooo
Landowners are alarmed by the spread of pink and purple flowers in the veld and wetlands. And they are confused about what to do.
What are these plants? Why are they a problem? What should be done to stop the spread?
THE PINK AND PURPLE PROBLEM
Each summer we notice the pink fluffy flowers spreading. Alongside that, in many places is a purple flower of similar height.
The pompom came first (image on the left). The verbena has taken hold and is as serious (right). Both plants flower in summer, die down in
winter and re-emerge after the first rain. They are perennials, meaning the plant from last season is the same plant which emerges in this season
– alongside all the hundreds of plants which have grown from seed.
Campuloclinium macrocephalum or pompom weed
Verbena bonariensis or Wild Verbena
DO WE HAVE TO DO SOMETHING ABOUT IT?
Yes. Look at what happens when pompom dominates in the veld….
The invasive pompom and verbena reproduce and spread prolifically and grow so densely that the natural grasses (and other plants!) are forced out. In
farmlands this reduces the amount of natural grazing available.
You may not have domesticated animals, but the loss of diversity in the veld has implications for ALL other lifeforms – fewer variety of insects,
birds, small mammals….Remember the food chain from your school days? The loss of any link in that chain has repercussions throughout.
AND, IT’S THE LAW….
Invaders threaten biodiversity, the environment, water resources and
economic activities.
Government’s response was to list all species which are threats as
“Invaders”. And, to help us as landowner prioritise action, all invaders are
categorised. Both pompom and verbena are in Category 1b.
The
1
category means “MUST be controlled”. Speficially :
“A person who is the owner of land on which a listed invasive species
occurs must (a) Notify any relevant competent authority, in writing, of the listed
invasive species occurring on that land;
(b) Take steps to control and eradicate the listed invasive species and to
prevent it from spreading; and
(c) Take all the required steps to prevent or minimise harm to biodiversity”
Pompom dominating the veld. Note that only cynodon dactylon or “couch grass” is
growing among the pompom. Biodiversity is very low
It seems clear that dealing with invaders is not optional if we are to be
law-abiding. Failure to control invaders can result in a conviction with a
fine and/or imprisonment.
The Act allows for R5 million fine, and for a second offence, R10 million.
Pelindaba/Voortrekker Monument….etc, etc.
1
I can hear you ask “What about government’s land?” The roads?!
Section 73(2) of the NATIONAL ENVIRONMENTAL MANAGEMENT: BIODIVERSITY ACT 1 0 OF 2004 (“Biodiversity Act”)
GOVERNMENT’S RESPONSIBILITY
There are many reasons to be despondent, and plenty of excuses to avoid taking responsibility. The bottom line is having a duty of care. It can
also simply come down to economic sense: land is an asset that depreciates if not cared for. For most people, it is the biggest single investment
they make.
Does it make sense to allow our own assets to degrade because government fails in this duty? No. We, as a collective, can apply pressure on
organs of state to do what is required. An active, involved community can use existing structures to bring about change/action.
It only demands piles of patience, and heaps of effort. Alternatively, we plough that energy and effort into just doing it for ourselves, and
enjoying the outcome of that effort.
GOOD FOR SOMETHING?
Fields of pink flowers must be good for something – right? What about being a great
food source for bees?
Perhaps. Most specialists agree that it is mono-culture causing the decline in bee
pollutions. Invaders take over, and actually create fields of one dominant plant – just
as the farmers of single crops do! We sacrifice biodiversity and habitat when invaders
proliferate, so yes, there is grave concern for bees. It seems imperative to halt the
invasion by pompom and verbena!
But we should not be irresponsible with treatment either. When using the herbicide
on a plant that is already in flower, REMOVE THE FLOWERS.
Not just for the
protection of bees, but also to reduce the number of seeds floating in the wind.
The BEST solution all round is to use herbicide WELL BEFORE FLOWERING commences.
No problem to insects and cheaper for you.
Young pompom plants among scattered grasses. This is the
time when treating pompom is most effective.
Observation from the veld:
A fallen or cut flower still forms seeds. Drop the cut flowers into a bag, never the veld. Tie that bag really
tight, and keep the cut flowers out of the wind.
The herbicide hits the flowers quickly. Within a day or two, the flower stems are drooping (see photo)
and less attractive to all insects. Small buds shrivel and crumble when touched.
WHAT DO WE DO?
Get out there and treat the problem NOW.
And, begin again in September / October.
Take
photographs so that you remember what the veld looks like covered in pink. The plants are not going to
suffer some catastrophe during the winter.
Certainly, they will grow again. The pompom does not
“appear” fully formed with flowers on. It is an easily recognisable plant which begins growing in spring.
The photo on the left shows a stretch
where a corridor alongside the road
was treated in December 2014.
Roadside are treated to limit the
spread of seed by cars and people
passing close to the plant.
When treated, the pompom plant
had only leaves, no flower stalks.
The flowering plants on the left show
the change in a month to six weeks.
The pompom on the right have died.
Next season there WILL be pompom
on the right, and those will be new
plants growing from the mass of seeds
produced on the left.
WHAT’S THE HURRY?
According to the landowner of the property in the photo below, it took only 2 years to become this dense and spread over the entire property.
The more invaders present, the higher the cost and effort.
Invaders, by definition, spread rapidly. Pompom and verbena are
especially vigorous in 



disturbed soil,
degraded veld,
overgrazed veld or
places where water gathers, even for a short time.
One way to stall infestation is to have a healthy veld, free of rubble or
disturbance, and to monitor and control grazing.
Ideally, there must be good vegetation cover and a rich variety of plants
and grasses.
FINANCIAL DRAIN
A welcoming space for all kind of invaders and weeds
The economic implications of a tardy and uncoordinated response are significant: each successive untreated season adds exponentially to the
cost to clear. The costs peak when the invaders dominate. The veld will need to rehabilitated to restore its health, certainly rested from grazing
for several seasons.
I have heard landowners say “We work and work, and the pompom gets no less”.
If you do the same thing every year, and the situation gets
worse, you need to change what you are doing. You may have been very effective in dealing with the SPECIFIC plant; it may be dead. But
this is the problem: If you have not done more to prevent re-seeding, expect at least the same number of plants again next year – or, more
likely, a significant increase. If you have sprayed late, and seeds have fallen, the problem grows.
Coordinate efforts: If you have cleared your
property well and in good time but your
neighbour has been negligent, you can
anticipate another flush of pink and purple
next season.
The photographs show two properties and
two standards of care, separated only by a
dirt road.
ACTIONS AND SOLUTIONS
Action tried
Cutting off the flowers
Digging it out
The problem
Well, that is all you are doing - cutting off a
flower only prevents THAT flower from seeding.
If you cut while the plant is healthy and
growing, you have stimulated it to produce
more flowers.
You have to dig out EVERY scrap of the plant –
or the same plant will just appear again,
perhaps even more than one if you have left
bits of root behind.
Burning the veld
Pompom and verbena are just like our veld
plants – adapted to survive fire. Their rhizomes
store enough energy to kick-start the growth
after a fire.
Using herbicide other
than those registered
for the purpose (i.e.
cheaper
herbicide
such as Roundup)
You spray the plant with great care, and it
seems to be dying. Only after weeks it has not
died “properly”. So you dig it up, or you apply
some more herbicide…spending more time
and more money on the same (rapidly ageing
towards seeding) plant.
The Solution
Only cut the flower after you have applied herbicide.
Better yet, apply herbicide BEFORE the flowers appear. You will save
time and effort.
If you have VERY FEW pompom, mechanical removal is an option. Do
it carefully, digging deep and wide around the plant. DESTROY the
whole plant.
TIP: Walk into your veld and count the pompom. If you tire counting
the pompom, there are too many to remove in this manner. Work out
how long it will take to remove the pompom you have counted, and
ask yourself if you have that amount of time before the flowers turn to
seed. If no, get out the herbicide.
Burn only in these circumstances: Your veld is moribund (thick with old
matted material). You have the permission of the Department of
Agriculture. You have consulted with the local “fire chief”, presently
Howard Biccard. You have enough appropriate fire fighting
equipment and people on hand to prevent the fire spreading. The
first spring rain of more than 15mm has fallen. Once burned, wait until
the pompom has 4 or more leaves, and then apply herbicide. It will
be very easy to spot in the open veld.
The herbicides that are registered have been proven to be effective.
They cost more, and they get the job done.
We have tested several products, each has pros and cons.
There is one in a fine powder form that needs constant agitation.
Unless you are prepared to constantly stop and stir, or shake, avoid it.
There are granules that take longer to drop out of suspension, but will
still need agitation.
Herbicides that come in liquid form are easier to use. We use Plenum
as it has a shorter half-life than its predecessor, Access. Both are from
ECO Guard (www.ecoguard.co.za). Both presently cost a little more
than R1 per liter in the sprayer.
OBSERVATIONS
EFFECT OF CUTTING FLOWERS
Cutting the flowers at the wrong time is ineffectual and wasteful. Here are case examples: The
typical central stalk is cut (circle) and 6 new stems and flowers grow quickly. This photograph was
taken where the landowner employed six people to work end-to-end cutting flowers. Before they
were half-way, the veld where they had started had turned more pink than before!
The photograph below indicates where stems were cut (see circles). Within days new stems had
formed. Beyond the plants with the small buds, the more mature flowers on un-cut plants.
Landowners might buy themselves time by
cutting flowers but as the only effort to
control invaders, it fails.
Rule of thumb: what takes one day to spray
takes three days to cut and bag.
A blue dye is added to the herbicide to make it clear where is has been applied. It ensures that
plants are not inadvertently sprayed twice. Workers can move quickly when the dye is clearly
visible – they don’t need to pause to check if the plant has been sprayed. The team works in a
fairly tight configuration. It helps to ensure that plants are not overlooked.
Can you spot the pompom? This is the best time to deal with the invader. The plant is small and it
takes little herbicide to destroy it.
The pompom begins wilting (above) and will be in obviously distress from
about day 3. After 2-4 weeks (depending on conditions and the size of the
plant)it will die, and decompose to nothing (right)
A COHESIVE RESPONSE
– STRATEGIES THAT WORK
Keep the roadways clean:
This reduces opportunities for seed to be
mobilised and carried into areas not affected.
A flower head
heavy with seed is easily swept up by vehicle movement,
pedestrians or animals. Hitching a ride, the seed can travel far
and begin to take hold in another area.
Photo: A “timebomb” of seed waiting on the roadside to be
swept along.
Cut off the supply line: The flowers bear thousands of seeds, and
seed is one of the most effective ways for invaders to spread. Stop
the flower, stop the spread. But it is NOT enough to cut off the
flower. Rather, kill the plant before the flowers form. Not only do
you stop that plant spreading, but you save on all the effort, cost
and risk of dealing with the flowers.
Act together: Think of the invasion in a tactical manner. It is absolutely necessary to all work together. If your neighbour is not doing their bit,
offer to help. Get involved. Solve the problem.
Neighbour absent/unknown? Get a working team together and tackle it locally to help everyone in the long term.
Use the registered herbicide: It seems people are willing to try any herbicide, and generally this leads to a waste of effort, time and money.
Herbicides which are registered have been proven to work. Use – Plenum by preference (tested locally), Access, or Brush-off. Do NOT use
herbicide in water catchments or near your borehole.
THE WAY FORWARD FOR THE CHARTWELL CONSERVANCY in eradicating Pompom weed and Wild verbena.

Inform Landowners about Pompom weed and Wild Verbena

Identify areas where pompom weed and wild verbena are growing. We can map these areas and contact landowners who are not aware of the problem, in order to gain
their cooperation and involvement.

Together with CCE, agree on a managed solution for dealing with the problem. CCE will need to work on eradicating the weed on verges and common land.