Killer Plants

A hungry fly tiptoes across a sweet-smelling leaf, looking for a meal. Suddenly the leaf closes around it! This insect has been caught by a carnivorous plant—one that attracts and kills animals for food. There are more than 600 species of these types of plants around the world.

Like all plants, carnivorous plants make their own food using photosynthesis. Powered by the sun’s energy, they combine water and carbon dioxide to make sugar. Plants also suck up nutrients from the soil through their roots.

But carnivorous plants grow in wetlands and bogs, where the soil is low in nutrients. To survive, they have developed the ability to feed on small animals. “It’s a way to get nutrients the soil can’t provide,” says Liane Cochran-Stafira. She’s an ecologist at Saint Xavier University in Chicago. Read on to learn about the traps these plants use to capture prey.

A hungry fly walks across a sweet-smelling leaf. The bug is looking for a meal. Suddenly, the leaf closes around the insect! It’s been caught by a carnivorous plant. The plant attracts and kills animals for food. More than 600 kinds of these plants exist around the world.

Like all plants, carnivorous plants make their own food through photosynthesis. Plants soak up the sun’s energy. They use it to combine water and carbon dioxide gas to make sugar. Plants’ roots also suck up nutrients from the soil.

But carnivorous plants grow in wetlands and bogs. There, the soil is low in nutrients. These plants survive by feeding on small animals. “It’s a way to get nutrients the soil can’t provide,” says Liane Cochran-Stafira. She’s an ecologist at Saint Xavier University in Chicago. Read on to learn about the traps these plants use to capture prey. 

The Venus flytrap, which grows in North and South Carolina, uses a snap trap to snag its meals. The plant’s clam-shaped leaves have tiny hairs inside. If an insect touches them, the leaf snaps shut. Fluids help digest the prey. After about 10 days, the empty trap reopens.

Sometimes a falling leaf tricks the Venus flytrap into snapping shut. But it isn’t fooled for long. If the “food” doesn’t move, the trap opens back up, ready for a meaty lunch!

The Venus flytrap grows in North and South Carolina. It uses a snap trap to snag meals. The plant has clam-shaped leaves. They have tiny hairs inside. The leaf snaps shut if an insect touches the hairs. Fluids help digest the prey. The empty trap reopens after about 10 days.

Sometimes, a falling leaf tricks the Venus flytrap into snapping shut. But it isn’t fooled for long. The trap opens if the “food” doesn’t move. Now it’s ready for a lunch made of meat!

Meat-eating plants with lobster pot traps confuse insects to draw them in. One example is the parrot pitcher plant, found in the Southeastern U.S. Each of its tube-shaped leaves has nectar around its opening. An ant may crawl into the opening in search of more sweet liquid. But the deeper it goes, the narrower the tube becomes.

To make things more puzzling, pale spots on the leaf let in sunlight. The insect can’t tell where the exit is. “Once they’re in, it’s very hard for them to get out,” says Leonora Bittleston, a biologist at Boise State University in Idaho. Eventually, the ant runs out of energy. The plant releases digestive fluids to help it break down its meal and absorb the nutrients.

Some meat-eating plants use lobster pot traps to draw in insects. One example is the parrot pitcher plant. It’s found in the Southeastern U.S. It has tube-shaped leaves. Each one has nectar around its opening. An ant may crawl into the opening looking for more sweet liquid. But the deeper it goes, the narrower the tube becomes. 

Pale spots on the leaf let in sunlight. This further confuses the insect. It can’t tell where the exit is. “Once they’re in, it’s very hard for them to get out,” says Leonora Bittleston. She’s a biologist at Boise State University in Idaho. Eventually, the ant runs out of energy. The plant releases digestive fluids. They break down the meal and help the plant absorb the food’s nutrients.

Plants with adhesive traps use super-sticky mucus to catch prey. Sundews, which live on every continent except Antarctica, have leaves that are lined with long, flexible tentacles. On the tip of each tentacle is a drop of nectar mixed with a sticky substance. When an insect lands for a drink, it finds itself glued in place. The plant then wraps its tentacles around its helpless victim. Within about 15 minutes, it smothers the insect.

Over the next few weeks, the sundew’s leaf releases digestive fluids. They break down the insect’s body, and the plant soaks up its snack.

Plants with adhesive traps catch prey with super-sticky goo. Sundews live on every continent except Antarctica. They have leaves lined with bendy tentacles. On the tip of each tentacle is a drop of nectar. It’s mixed with a sticky substance. An insect lands for a drink. It finds itself glued in place. The plant wraps its tentacles around its victim. It smothers the insect in about 15 minutes.

The sundew’s leaf releases digestive fluids. They break down the insect’s body. The plant then soaks up its snack.

The trap used by the bladderwort is the size of a fingernail. But it’s one of the quickest killers of all carnivorous plant traps. The bladderwort grows in water around the world. It eats tiny critters like insect larvae.

The bladderwort is covered in hollow pouches, called bladders. To set its trap, the plant pumps all the water out of the bladder. Like squeezing the bulb of an eyedropper, this creates suction inside the pouch. When a tiny animal rustles the plant’s hairs, a door-like flap opens. Water rushes in to fill the trap, and the prey is sucked in too.

The trap used by the bladderwort is small. It’s just the size of a fingernail. But the trap kills prey quickly. The bladderwort grows in water around the world. It eats tiny critters like insect larvae.

The bladderwort is covered in hollow pouches. They’re called bladders. The plant pumps all the water out of the bladder to set its trap. It’s like squeezing the bulb of an eyedropper. This creates suction inside the pouch. A tiny animal rustles the plant’s hairs. A door-like flap opens. Water rushes in to fill the trap. And the prey is sucked in too.

Pitfall traps are the most common way for carnivorous plants to capture creatures. These traps are used by many species of pitcher plants, which grow all over the world. The leaves of the purple pitcher plant look like colorful petals. And they are coated in sweet nectar. But the leaves are extremely slippery. A hungry insect creeping onto the rim will slip and fall into a pool of liquid in the plant’s base.

The leaf walls are covered in stiff, downward-pointing hairs. This makes it nearly impossible for an insect to climb out. Digestive fluids in the pitcher break down the animal’s soft body parts. Some pitcher plants are wider than a basketball. In addition to insects, they can catch small animals like mice!

Pitfall traps are the most common way carnivorous plants capture creatures. These traps are used by many species of pitcher plants. They grow all over the world. The leaves of the purple pitcher plant (right) look like colorful petals. They’re coated in sweet nectar. And they’re very slippery. A hungry insect will creep onto the plant’s rim. It slips and falls in a pool of liquid in the plant’s base. 

The leaf walls are covered in stiff hairs. They point down. This makes it hard for an insect to climb out. The pitcher plant contains digestive fluids. They break down the animal’s soft body parts. Some pitcher plants are wider than a basketball. As well as insects, they can catch small animals like mice!