Mikania micrantha An Invasive Weed, help stop it now
“Florida is a constant target for invasive plants, pests and diseases. This is mainly
due to its geographic location as well as an increase in global trade and travel. State
and federal agricultural agencies work hard to stop these introductions through the enforcement
of stringent regulations and through extensive survey, but it is impossible to stop all introductions.
A recent example is right around the corner.”
“Here we are at a large infestation of Mikania micrantha, in the Redlands area of Miami-Dade
County, which is actually the first place where this weed was found in the United States.
Now we’re standing on a roadside which is where you will commonly find this plant. It’s
a real threat, not only because it is listed on federal and state noxious weed lists, but
it is also considered one of the 100 most invasive alien species in the world. It is
a fast growing vine, and it is very prolific. And as you can see, behind me the vine will
actually grow up into the trees, covering trees and the surrounding plants, and it chokes
out the sunlight. Furthermore, they have thousands of flowers and each one of these white flowers
turns into a little seed cluster. That seed cluster is then spread by wind very similar
to a dandelion. And that is one of the reasons why this is such a threat.”
Left uncontrolled, Mikania micrantha can cover disturbed areas in only a few months, and
then spill over into agricultural areas. It can smother and overwhelm other small plants
and even large trees. It has been documented as a pest in banana, cacao, coconut, oil palm,
rubber and rice plantations.
Like old world climbing vine and kudzu, which have already invaded Florida, it could quickly
change the landscape.
However, because Mikania micrantha has been discovered early, it may be possible to slow
or stop the spread and potential destruction to Florida’s natural and agricultural areas.
State and federal agricultural officials are surveying to determine the extent of the weed’s
spread, and the University of Florida’s Institute of Food & Agricultural Sciences
is developing control methods.
“In addition to Mikania micrantha, there are two native species of Mikania to Florida
– Mikania scandens and Mikania cordifolia. Let’s see if we can find some examples.”
“We are standing here in a South Florida subtropical hammock, and we’ve got an example
of Mikania scandens, which is one of our native Mikania species. What’s different about
this one compared to Mikania micrantha, which is the invasive species, is the flowers actually
have a pink tint to them. Also, this habitat is very indicative of where you’ll find
Mikania scandens, which is kind of shady, moist, undisturbed. Mikania micrantha prefers
areas where there has been some disturbance, such as on hedges. It will grow along fences,
and it also tends to grow up very rapidly and cover those plants. Mikania scandens tends
to grow out, it will grow up into the plant, but it tends to grow out more than the invasive
species.”
The other similar species, Mikania cordifolia, has hairy leaves and stems and larger flower
heads compared to Mikania micrantha and Mikania scandens.
Though managing micrantha may prove to be difficult, steps are being taken to limit
its negative impact:
Plant nurseries are inspected regularly and will be kept free of the weed to ensure market
viability if that weed is found, that location is quarantined until removal and treatment
is completed.
Backyard gardeners are being educated in proper removal methods, as well as how to distinguish
between native and invasive Mikania species. Managers of natural areas are being vigilant
about destroying Mikania micrantha. “You can see it is growing up all through
this area. Yeah, you can see it all over that tree. Yes, it is growing all over that, covering
the bushes here. Yes, we need to remove this.”
“Removal of plant material is essential to the control and possible eradication of
Mikania micrantha.”
“Alright, let’s get into it.” “Yes, I’m not even sure this is all Mikania.
It is definitely Mikania on the top, but underneath that could be air potato or coral vine. You
just have to rip it halfway through or otherwise the entire forest is going to come down.”
“You know we should probably double-bag this one because it is pretty full.
Make sure all the pieces are inside.”
“If you think you have Mikania micrantha, please remove it as thoroughly as possible
and for more information contact the Division of Plant Industry or your County Extension
office.”
To further protect Florida’s plant industry: * Report any suspicious plant pests or diseases
to the Plant Industry Helpline. * Don’t pack a pest – when you travel,
don’t pack food or other products in your luggage that might contain harmful pests and
diseases. * And only purchase plants from registered
nurseries.
“Unfortunately, this won’t be the last invasive plant that Florida has to deal with,
which is why the emphasis is on early detection. The division of plant industry will continue
to educate the public on the consequences of bringing in prohibited plant and agricultural
material. Please do your part to help keep Florida’s agriculture and natural areas
healthy.”