Can You Hear the Trees Talking?. Peter Wohlleben

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Can You Hear the Trees Talking? - Peter Wohlleben


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between the bare branches right onto the ground.

      The branches of conifers work well to shed snow,

      but not so well to catch

      rain.

      Because conifers are

      narrow at the top and their branches angle out or down

      rather than up, they act like umbrellas. This means the

      ground around the trunks of conifers often stays very

      dry, and in the summer the trees can be very thirsty.

      Being Thirsty Hurts!

      ft

      thirsty tree's trunk can tear when

      it

      tries

      to such water from dry ground.

      IF IT'S A

      VERY

      ORY

      SUMMER

      and

      spruces

      continue

      to

      suck water out of the

      ground,

      especially greedy

      trees can split open along the length of their

      trunks.

      That's a

      bad

      injury for

      a

      tree.

      Thick drops

      of pitch seep out of the wound (pitch is like the

      blood of the spruce tree], and the wound never

      really heals. That tree will have a

      long,

      seeping

      scar down its bark for the rest of its life.

      With their wide crowns, beech trees con capture a

      lot of

      rain and direct

      it

      down their trunks

      to

      the ground.

      Just like other living things, trees need water. And because they are the elephants

      of the plant

      world,

      they need a lot of it. On a hot summer day, a large beech

      tree can easily drink up three or four bathtubs full of water.

      OF COURSE,

      THERE

      ARE NO

      BATHTUBS

      in the forest,

      which means that beech trees have to get every

      drop of water from the ground. They do this

      using their roots to feel for the spots where

      it's nice and moist.

      Once they've found a moist spot, they

      quickly suck up all the water. And to make sure

      they really do get every last drop, the roots

      team up with fungi. Fungi grow fine threads

      around the roots of these forest giants and, like

      cotton balls, they soak up even more water for

      the

      trees.

      Different salts from the ground are carried

      into the tree trunks along with the water. The trees

      need these salts to grow, and they like

      them.

      It's like

      when you eat chips–once you start, you can't stop!

      We still don't really know how trees get water

      all the way up to their crowns. (Maybe you'll want

      to research this yourself when you get older.) What

      scientists do know is that it takes

      a

      lot of energy for

      trees to do this–more energy than you would need

      to blow up

      a

      balloon as big as a house.

      *

      In the winter, when the water in the ground freezes,

      the trees take a break from drinking. After all, you

      can't drink ice cubes. That's why, before they grow

      leaves again in the spring, they suck a whole lot of

      water up into their trunks in one big gulp. If

      you

      take

      a stethoscope (that thing the doctor uses to listen to

      your heart) and hold it up against the bark, you may

      actually be able to hear the water rushing up inside

      the tree. As soon as the tree leafs out, the water

      pressure drops back down.

      Trees that belong to the same species usually drink

      about the same amount. But some learn to drink

      a

      little

      less.

      During a hot summer, the ground can dry out.

      If

      a

      tree keeps trying to suck water from dry

      soil,

      its

      wood may crack. That helps it learn to do

      a

      better job

      of managing its water supply.

      Come

      the next spring,

      instead of drinking up all the water in May and June,

      it saves some for July and August.

      Some

      trees learn more quickly than others. There

      are reckless trees that drink a lot, and careful trees

      that prefer to conserve water, Fortunately, the careful

      trees are very nice to the others. When they notice

      that the ground is drying out, they warn their fellow

      trees through the fungi that act

      as

      the forest internet.

      (You can read all about this in Chapter 3.) When the

      news gets out, even trees that like to guzzle water

      begin to cut back.

      *

      The


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