We Should Be Worried about the Plant That Can Count.

Coutesy of Joe MiGo

Coutesy of Joe MiGo

While working on my graduate studies in North Carolina I was lucky enough to enjoy the amazing wildlife of the area. North Carolina is home to many fascinating species but one the most captivating is the Venus fly trap. As of now, these plants are considered vulnerable to extinction and their situation only grows more precarious every year. I was to be able to see Venus fly traps in the wild, but future generations may not be so lucky if we don’t clean up our act.

Few plants have inspired such delight and mystery as the Venus fly trap. That allure is causing their downfall.


A Small Range

What many people don’t realize is how small a range Venus fly traps have. They require such specific conditions to live that they are restricted to a hundred mile stretch along the coastal wetlands of North and South Carolina. While an estimated 30,000 fly trap plants remain in the wild, these plants are found only at 100 sites. This restricted habitat leaves Venus fly traps especially vulnerable to the effects of poaching and climate change.


Courtesy of Mnolf

Courtesy of Mnolf

The Hungry Plant

The Venus fly trap is most famous for its diet. They live in nutrient-poor environments so have evolved to take nitrogen and other vital nutritional factors from the bodies of insects that they catch within their sticky traps.

The fly trap is the product of thousands of years of evolution. The two “jaws” of the trap are actually modified leaves. On the inner surface of each trap are numerous trigger hairs. These short and stiff bristles are triggered by movement, letting a fly trap know when to close onto unsuspecting prey. When a trap is triggered it will close quickly, using the vein in between the two jaws of the trap as a hinge.

Once prey is locked within their “jaws,” the trap seals shut and digestion begins. Specialized glands secrete digestive enzymes into the enclosed space. When digestion is complete the trap springs open again. No trap lasts forever. Traps generally can close between 3 – 4 times before they wither and fall off the plant. Because of this, it’s important that you don’t falsely trigger a fly trap. It takes the plant a lot of energy to make a new trap!  

Courtesy of Plenz

Courtesy of Plenz


A Plant That Can Count?

Courtesy of Martin Brunner Closeup of a trigger hair.

Courtesy of Martin Brunner

Closeup of a trigger hair.

Recently, research has uncovered a mind-boggling secret of the Venus fly trap: They can count.  The trigger hairs on a trap signal for the trap to close but they don’t do it for just a single touch. It takes two touches within 15-20 seconds for a trap to close. These two touches send electrical signals to the trap’s center that causes the trap to close.

It’s very advantageous for fly traps to “know” when to close. If they reacted to only one touch of a trigger hair then they might close on rain drops and insects that weren’t fully in the trap. Though it only takes two touches for the trap to close, it takes five for digestion to begin. More touches can cause the fly trap to boost its digestive processes, in the case of big meals!


Courtesy of юкатан

Courtesy of юкатан

A Dangerous Plant in Danger

Fly traps only can grow in very specific conditions. They have always been somewhat rare in the wild but each year they only become rarer. Thousands of plants are uprooted by poachers each year. This is an especially sad fate for wild Venus fly traps, as they can be readily grown in greenhouses. Up until recently, poachers would only suffer minor penalties if caught, a fine of between $10 – 50 per plant. Without any threat of jail time, this wasn’t much of a deterrent for the plant thieves.

In 2014, a poacher was caught with thousands of plants, about 1% of the wild population. This spurred North Carolina lawmakers to finally enact stronger laws to protect wild fly traps. Now, fly trap poaching is a felony. Those convicted of poaching can face up to 25 months in prison.

Some of the poached fly traps undoubtedly end up in pots and sold as houseplants, but the bulk of them have a darker fate. Venus fly traps are a component of certain herbal supplements. There is no evidence that consuming Venus fly traps is beneficial but the industry roars on. 

In short, we should be worried about the plant that can count because they may not be able to survive in the wild for much longer. 

- Kate Dzikiewicz, Paul Griswold Howes Fellow