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  • It's winter where I live

  • ...and a lot of trees have lost their leaves!

  • The leaves turned brown, or yellow, red, and even purple and then they fell off the trees.

  • But some trees are still green!

  • In fact, it seems like these trees don't ever turn brown -- they stay green all of

  • the time!

  • That's why we have a special name for these kinds of treesevergreens!

  • Depending on where you live, you might have some well-known evergreens in your neighborhood.

  • These include pine, fir, and spruce.

  • These trees are easiest to recognize by their leaves.

  • And yes!

  • Those thin, pointy, things on these trees are actually their leaves!

  • We usually call them needles, because that's what these leaves look like!

  • Some needles are long and soft, and others are short and sharp.

  • When needles get old, they do fall from the tree, but usually just a few at a time, and

  • the tree grows new ones very quickly.

  • So the trees stay green all year round.

  • Now, even though needles don't look like the leaves on other trees, they have the same

  • jobto catch sunlight.

  • The tree then uses the sunlight to make energy.

  • And energy helps the tree grow!

  • Of course, evergreen trees also need lots of water, just like most other plants.

  • But in many places, rain doesn't fall very often during the winter.

  • And trees can't use the water that's frozen into ice and snow.

  • So a tree needs to hold on to the water inside it, for as long as it can.

  • And the thin needles you find on evergreens help keep the water inside those trees, because

  • they're covered with a thin layer of stuff that's kind of like wax.

  • This waxy layer helps trap water inside the needles, so the tree doesn't dry out.

  • Another thing you might know about pine, spruce, and fir trees is that they make these neat

  • little things called cones.

  • Cones can be big...or very small...and even colorful!

  • A cone's job is to make the seeds that will someday grow into new trees!

  • In fact, if you look deep inside a pine cone, you'll see the seeds inside.

  • These seeds are a tasty snack for animals like squirrels, chipmunks, and birds.

  • And evergreens that have cones also have a special name.

  • This group of plants is called conifers.

  • The name has the wordconeright in it!

  • And pine, spruce, and fir aren't the only conifers out there!

  • Some of the biggest conifers in the world are known as giant sequoia trees.

  • Giant Sequoias live in the Western United States, and they live up to their name -- because

  • they can grow to be enormous.

  • Many of these trees are wide enough to drive a car through.

  • One of these trees is almost eighty four meters tall, and about eleven meters wide.

  • It even has a name: General Sherman.

  • And scientists say that, while it's not the tallest tree in the world, it's the

  • biggest, heaviest tree overall.

  • Trees like General Sherman grow to be so big, because they live for a really long time.

  • Some sequoias can live for over three thousand years, making them some of the oldest living

  • things on the planet.

  • Now, you might see lots of pictures or drawings of conifers in cold and snowy places.

  • But they don't only grow where it's cold!

  • Some of the most common plants in hot, dry places are conifers, too -- like the cedar

  • and the cypress.

  • And many evergreens in these places have a different kind of leaf.

  • Instead of being thin and pointy like a needle, cedar leaves are thin and flat.

  • This kind of leaf is called a scale, and they do seem a little like the thin and flat scales

  • of a fish.

  • Just like needles, scales help the evergreen save water, so it can stay green even when

  • it's very dry.

  • Okay, let's talk about one more evergreen.

  • This one is known for its broad, flat leaves and brightly colored berries.

  • Right you are Squeaks!

  • It's holly!

  • Holly is an evergreen with leaves that are often dark green and prickly around the edges.

  • And just like needles, holly leaves have a shiny coating on them that helps them save

  • water when it's dry.

  • Holly is not a conifer, so it doesn't make cones.

  • Instead, the seeds of holly plants are found inside the berries.

  • Although the most famous kinds of holly have red berries, some holly plants make berries

  • that are white, orange, or even black.

  • So even when it's wintertime, many kinds of trees keep their green!

  • Here's hoping you get outside and have a chance to see some of these excellent evergreens

  • this winter!

  • Thanks for joining us on SciShow Kids!

  • Do you have a question about something in the world around you?

  • If so, ask a grownup to help you leave a comment down below, or send us an e-mail to kids@scishow.com!

  • Thanks!

  • See ya next time.

It's winter where I live

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永不落叶的树木(Trees That Never Lose Their Leaves! | Science for Kids)

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    joey joey 發佈於 2021 年 05 月 10 日
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