Plant Nature Study I by Various Plant Nature Study I by Various    

Lesson 16: A Trap for Living Insects (Carnivorous Plants)

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Tommy Tit the Chickadee had stopped in the dear Old Briar-patch for a brief call on Peter Rabbit. Tommy knew all about Peter's interest in flowers. "I suppose," said he, "that you know that the insect eaters are in bloom." His eyes twinkled with mischief.

"Insect eaters in bloom? What are you talking about, Tommy Tit?" Peter wrinkled his brows in a funny, puzzled way.

"I'm talking about the plant that catches and eats insects," replied Tommy Tit.

There isn't such a thing," declared Peter. How can a plant catch insects? What nonsense!"

Tommy's eyes twinkled more than ever. "There is no nonsense about it," he declared. "There is a plant that catches insects for food, and if you had half used your eyes in the past, you would know the plant I mean."

Now Peter had never known Tommy Tit to tell him a thing that wasn't so. Still Peter couldn't quite believe this. He thought Tommy must be joking and said so.

"No," replied Tommy Tit, "I'm not joking. You think you have found out a lot about plants, Peter, but what you have found out is nothing to what you have yet to learn. There are several kinds of plants that catch insects and use them for food, just as we birds do. But I don't ask you to take my word for it. Just run over to the edge of the swamp and see for yourself. I hope the next time I make you a call you will not be so impolite as to doubt my word. Good-by, Peter."

"Wait a minute, Tommy Tit! Wait a minute!" Peter cried. But Tommy was already on his way to the Old Orchard and didn't turn back.

Of course Peter fairly ached with curiosity. He waited only long enough to make sure that the way was clear. Then he started for the swamp as fast as his legs could take him, lipperty-lipperty-lip. "I don't believe it because I can't believe it," said he to himself. "But if it is so, I am going to find out, though how I am going to do it I don't know. Tommy Tit might have told me what kind of a plant to look for. As it is I haven't the least idea. Anyway, if I don't find it I won't be disappointed, because I don't believe there is such a plant."

Just on the edge of the swamp the ground was boggy, and great masses of a certain kind of moss grew. Peter hesitated. He didn't want to get his feet wet. Then out in the middle of that boggy place he saw something which for the moment put all thought of what he had come for out of his head. He no longer thought about wet feet, but hurried over to it. It was a flower. There was no doubt about it. But it was a flower wholly unlike any Peter had yet found.

It nodded from the top of a long, smooth, light green stalk, and was quite as high above the ground as the top of Peter's head when he sat up. It was a large flower, quite two inches across. There were five sepals which were purplish-red on the outside and light green on the inside. There were five petals, and these were also a purplish-red. They were odd in shape, for they narrowed in the middle and then rounded out broadly, and these rounded ends folded over a big round part which was really a part of the pistil, though Peter had never seen anything like it before. It was like a little umbrella spread over the case which later would hold the seeds.

But odd as was this flower the leaves of the plant were even more odd. They grew out in a circle around the base of the flower stalk, and each leaf was like a little purple and green pitcher with a little hood at the top. Perhaps it would be nearer the truth to say that each leaf was like the curved horn of a cow with the narrow part at the bottom, and with a thin, broad wing on the side which curved in.

Just out of curiosity Peter peeped into one of these hollow leaves. It was half filled with water. He peeped into another and found this partly filled with water. It was the same way with every one of the leaves of that plant, for Peter looked into every one to find out.

But it wasn't the water that surprised him most. No, sir, it wasn't that at all. It was the fact that in every one of those leaves were many drowned Flies and insects. Peter hardly gave the matter a thought when he saw them in the first leaf into which he looked. But as he looked into leaf after leaf and found that the same thing had happened in each, he began to wonder. At first he thought these little Flies and insects had been accidentally drowned. Then he began to wonder how they had happened to go into those leaves.

And then quite suddenly he remembered what Tommy Tit had said. Could this be the plant that made a business of catching insects for food? Peter backed off a step or two and stared at that plant as if he were just a little bit afraid of it. Of course he wasn't really afraid, but the idea that he might be looking at a plant that lived in part on insects, just as so many of his feathered friends did, gave him a strange feeling.

As he sat there staring he saw a little Fly alight on the edge of one of those leafy cups or pitchers. Peter leaned forward to watch. It was plain there was something just inside that pitcher that was very tempting to the little Fly. Peter could tell that by the way the Fly acted. It crept inside, then suddenly slipped and fell!

Of course it fell in the water. But it fell at one side and not in the middle. Thus it was able to start to climb up without getting very wet. But it couldn't climb up very far. It had climbed but a little way when again it slipped and fell. This led Peter to look into that cup more closely, and he found that there were tiny hairs on the sides pointing down. These were what prevented the little Fly from climbing up. Then the little Fly tried to fly straight up, but hairs at the top prevented its escape, and down it fell again. Each time it got a little wetter, and each time it had less strength. Finally it could do nothing but struggle helplessly on the surface of the water, and after a little these struggles ceased. The little Fly had been drowned.

Then Peter understood. These pitcher-like leaves half filled with water were traps. The unlucky Fly or insect tempted to enter by a sweet juice just below the edge was almost certain to fall, and once in had very little chance of getting out. It was quite clear that the strange shape of these leaves was well adapted for catching insects, and of course that meant that the plant must get part of its food from them instead of getting all of it from the ground through the roots as most plants do. It was hard to believe, but Peter could not doubt his own eyes. He sat there for a long time and saw the same thing happen over and over again.

This strange plant is called the Pitcher Plant, the Huntsman's-cup and the Indian Dipper. But the first name is the most common one. It belongs to a family of its own.

Late that afternoon Jenny Wren happened over to the dear Old Briar-patch and at once Peter started to tell her about what he had seen that morning. "Tut, tut, tut, tut, Peter. I know all about it," said she. "Way down south where I go in winter are several other members of the family, one of which has leaves that, instead of being curved, grow straight up and are like a trumpet with the small end springing from the ground. Over the top is a flap something like the flap Jack-in-the-pulpit has over his head. I have peeped into one of those leaves and seen it nearly filled with dead insects."

"Ugh!" exclaimed Peter. "I can't make it seem right that a plant should get part of its living in the same way that Old Mr. Toad and most of the birds do."

"Right or wrong, the Pitcher Plants do it, and there are a number of other plants that do it, too. And why shouldn't they? Insects are very good eating, very good eating," replied Jenny Wren.

    Plant Nature Study I by Various Plant Nature Study I by Various    

Lesson 16: A Trap for Living Insects (Carnivorous Plants)

Directions

Study the lesson for one week.

Over the week:

  • Read the story.
  • Review the synopsis.
  • Recite aloud the vocabulary words and their definitions.
  • Learn the concepts.
  • Complete the enrichment activities.
  • Study the review questions.

Synopsis

Tommy Tit the Chickadee tells Peter Rabbit that insect catchers are in bloom next to the swamp. Peter finds it hard to believe that flowers eat insects, but he hurries to the boggy, mossy swamp to see for himself. Peter finds the Pitcher Plant, which grows its own water-filled cups to trap and drown insects. These plants produce a sweet juice to lure their insect prey into their cups and line the cups with downward pointing hairs to prevent the insects from escaping.

Vocabulary

Carnivorous: Capable of trapping insects and absorbing nutrient from them.
Boggy: Having the qualities of a bog; i.e. dank, squishy, muddy, and full of water and rotting vegetation.
Moss: Any of various small, green, seedless plants growing on the ground or on the surfaces of trees, stones, etc.
Pitcher: A wide-mouthed, deep vessel for holding liquids, with a spout or protruding lip and a handle.
Prey: A living thing that is eaten by another living thing.
Bacteria: A microscopic, single celled organism.
Enzyme: A globular protein that catalyzes a biological chemical reaction.

Concepts

Carnivorous Plants:

  1. In the story, Peter watches a Pitcher Plant trap an insect. How does the Pitcher Plants trap and 'eat' insects?
  2. The rim of the Pitcher Plant is slippery with condensation or nectar, and the insects slip down into the trap.
  3. The Pitcher Plant has adaptations such as downward pointing hairs lining the trap's steep inner walls, making it hard for insects to climb back out.
  4. The insects drown and are slowly dissolved in the liquid at the bottom of the trap by bacteria, enzymes, or other mechanisms.
  5. The insects decompose into a mixture of minerals used by the plant, such as nitrogen and phosphorus.

Enrichment

Activity 1: Narrate the Story

  • After reading or listening to the story, narrate the story events aloud using your own words.

Activity 2: Examine other Carnivorous Plants

  • The Venus Flytrap
  • The Sundrew
  • Another Species of the Pitcher Plant

Activity 3: Continue Your Experiment - Which Soil is Best for Beans?

  • Continue to water the seeds. Keep the sand, rocks, or soil damp over the duration of the experiment.
  • Complete your third week of observations of the bean seeds.
  • Which seeds have growing well? Which seeds are faring poorly?
  • Use the gathered information to create the field book entry.

Activity 4: Complete a Field Book Entry   

As you conduct your experiment, complete page 20 in 'Science Field Book for Third Grade.'

Review

Question 1

What do Pitcher Plants eat?
1 / 5

Answer 1

Pitcher Plants eat insects.
1 / 5

Question 2

Why are Pitcher Plants carnivorous?
2 / 5

Answer 2

Pitcher Plants are carnivorous because they eat animals - namely insects.
2 / 5

Question 3

How do Pitcher Plants trap insects to eat?
3 / 5

Answer 3

Pitcher Plants trap insects to eat by drowning them in water-filled cups.
3 / 5

Question 4

What do some Pitcher Plants use as insect bait?
4 / 5

Answer 4

Some Pitcher Plants use a sweet liquid as insect bait.
4 / 5

Question 5

How do Pitcher Plants prevent insects from crawling out of their water-filled cups?
5 / 5

Answer 5

Pitcher Plants prevent insects from escaping by lining their cups with downward pointing hairs.
5 / 5

  1. What do Pitcher Plants eat? Pitcher Plants eat insects.
  2. Why are Pitcher Plants carnivorous? Pitcher Plants are carnivorous because they eat animals - namely insects.
  3. How do Pitcher Plants trap insects to eat? Pitcher Plants trap insects to eat by drowning them in water-filled cups.
  4. What do some Pitcher Plants use as insect bait? Some Pitcher Plants use a sweet liquid as insect bait.
  5. How do Pitcher Plants prevent insects from crawling out of their water-filled cups? Pitcher Plants prevent insects from escaping by lining their cups with downward pointing hairs.

References

  1. Burgess, Thornton. Burgess Flower Book for Children. Ithaca, Boston, Massachusetts. Little, Brown, and Company, 1923.
  2. Comstock, Anna Botsford and Gordon, Eva L., Handbook of nature-study (Twenty-fourth edition). Ithaca, New York Comstock Publishing Company, Inc, 1911.
  3. 'Pitcher plant.' Wikipedia. Wikipedia.org. n.p.
  4. 'Venus Flytrap Trapped Fly Photo by dugeot. {(CC0 1.0)}' Pixabay. pixabay.com/en/venus-flytrap-trapped-fly-catch-2667991/. n.p.
  5. 'Sundrew Photo by alexia59200. {(CC0 1.0)}' Pixabay. pixabay.com/en/plants-carnivorous-plants-1889169/. n.p.
  6. 'Sarracenia purpurea Photo by cyndywill. {(CC0 1.0)}' Pixabay. pixabay.com/en/sarracenia-purpurea-289451/. n.p.