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MLA Full: "Plants with Weapons!" YouTube, uploaded by SciShow Kids, 17 April 2018,
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APA Full: SciShow Kids. (2018, April 17). Plants with Weapons! [Video]. YouTube.
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Chicago Full: SciShow Kids, "Plants with Weapons!", April 17, 2018, YouTube, 03:53,
Squeaks and I love to watch animals eating outside.

This morning, we saw a bird eating some worms, and a frog eating some bugs, although some of the bugs flew away before the frog could reach them. We also saw a deer nibbling on some plants!

Squeaks and I thought for sure that the deer was going to eat a leafy plant in the yard, but for some reason, the deer took a tiny bite, and then left the plant alone. We were curious why the deer didn’t like that plant, so we went over to investigate. On the leaves, there was a white goo all around where the deer had bitten.

When we touched the goo, it was super sticky. We brought back a few leaves to help us identify the plant in our field guide, where there are lots of pictures of plants. It turns out, that plant was a dogwood tree. [Squeaks asks if it’s like a dog].

Good guess, Squeaks, but it isn’t really much like a dog. It does have a nice bark though! Dogwood trees have leaves full of a special, sticky goo called latex, which it uses as a defensive weapon — a way to stay safe from animals that might like to eat it.

Animals can usually try to run away from a predator, but plants can’t move! They have to find another way to stay safe, which is where their defenses come in. When animals like the deer we saw bite a dogwood’s leaves, they get a mouthful of that sticky latex. /Yuck./ Most animals don’t like to eat latex, so they don’t like to eat the plants that are full of it, like dogwood trees. [Squeaks says he wouldn’t like to eat it either].

Eating latex definitely doesn’t sound very good. Our dogwood uses its sticky latex, but lots of plants have other creative defenses as well. Can you think of any, Squeaks? [Squeaks thinks, then suggests thorns].

That’s a great one. Some plants will use sharp thorns or spines to keep animals from biting them. I definitely wouldn’t want to eat anything so pokey.

A plant called stinging nettle even has special oils on its spines that can make you itch if you touch it. /Yikes./ [Squeaks asks about plants that don’t have thorns]. You’re right, Squeaks, not every plant has spines or thorns. But some of the plants that aren’t sharp have special chemicals inside to make them less tasty for animals.

That’s what our dogwood tree was doing with its latex. Take a look at these other plants. Poison ivy has a special oil on it, just like stinging nettle, so it makes animals super itchy.

Skunk cabbage makes itself super stinky, so animals won’t be able to eat it without smelling something awful. I don’t think I’d want to eat a plant that smells like a skunk, either. Some animals aren’t very picky though, and they don’t mind if a plant smells bad, or even if it tastes bad.

So, some plants have a very effective defense that keeps almost all animals away. They’re poisonous. If an animal, like the deer we saw, eats a poisonous plant, they can get very sick. [Squeaks is worried].

Don’t worry, Squeaks, animals usually know to avoid eating poisonous plants. Many animals won’t eat plants that they know are poisonous, and if they see another animal get sick from a plant, they won’t eat that plant. Plants have so many amazing defenses, but no matter which one they’re using — thorns, smells, latex, or poison — there are always a few animals that find ways to eat them.

Lots of goats can eat thorny plants, and some deer can even eat little bits of poisonous plants. As animals find new ways to eat different plants, the plants have to come up with new defenses to stay safe, so there are lots of ways they do it. Next time we’re watching the animals outside, we can keep an eye out for other types of plants defending themselves! [Squeaks agrees].

I’m feeling a bit like a hungry animal, too! Let’s grab a snack first. What sort of defenses would you use if you were a plant?

Can you think of any new ways for plants to defend themselves? If you have an idea, have a grown-up help you leave a comment below, or send us an email at And if you’d like to keep exploring with Squeaks and me, click the subscribe button.

We’ll see you next time, here at the Fort!