Can You Hear the Trees Talking?. Peter Wohlleben

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Can You Hear the Trees Talking? - Peter Wohlleben


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      a

      tree never gets thinner, only thicker.

      That's a good thing, because the tree is also

      growing taller, and that means it's getting heavier. It

      needs a sturdy trunk to support its weight, just like

      you need

      a

      strong skeleton to support your growing

      body. That's why adults are stronger than children,

      and older trees are stronger than younger ones.

      There's something else trees have that makes them

      similar to people. Your blood flows through tiny tubes

      called arteries that run from your heart to every part

      of your body. Trees have to pump water from their

      roots

      all

      the way

      up

      to their

      crowns,

      so

      they

      have an

      extensive system of tiny

      tubes,

      too, called vessels.

      You might be able to see these water vessels if

      you

      look at the rings in

      a

      piece of wood—they look like

      small holes.

      But water only flows in the tree's outermost

      rings.

      That's why in the summer, if everything is

      working properly, a tree will be quite wet under

      its bark, Farther inside, the wood becomes drier.

      Nothing's happening there anymore, and the tree

      can't feel anything there, either. That's why it

      doesn't really matter if the inner wood begins to

      rot. Even if its trunk becomes hollowed out like an

      empty pipe, the tree will still

      be

      just fine,

      *

      But there's one more question. Why does

      a

      tree

      need

      a

      trunk at all? Couldn't its crown grow

      straight out of its roots?

      A

      tree needs a trunk so it can grow taller than

      all the other plants around it, Otherwise it would

      just be

      a

      bush. (Bushes don't have trunks.) Since

      they're the tallest plants in the world, trees

      don't need to be afraid of other plants. They can

      grow above them all—except for other trees, of

      course. [We'll find out later why there are some

      anxious oaks out there.)

      FIND

      A

      BIRCH

      LOG.

      If your family

      buys

      firewood,

      it

      will often

      have

      birch logs

      in It—you can

      recognize

      them by their white

      and

      black

      bark.

      If

      you

      don't

      have any firewood at home, ask your friends

      who have fireplaces or fire pits.

      Spread some dish detergent over one end of

      the log. Now press your lips against the other

      end

      and

      blow.

      If

      the

      experiment works properly,

      you'll see soap

      bubbles

      coming

      out.

      That happens

      because the air you blow travels through the

      water vessels in the wood until it reaches the

      soapy film at the other end.

      A full-grown tree is very heavy. It can weigh more than five cars, and its trunk

      needs to be really strong so it doesn't collapse under all that weight.

      Big trees like this southern live oak need wide

      trunks to support the weight of their crowns.

      You can tell from these rings

      how old the tree was when

      it was cut down. Count the

      rings from the outside to the

      middle—the middle ring is the

      tree when it was one year

      old,

      Of

      course,

      you can't count

      the rings when a tree is still

      alive because they're under

      the bark—you can only see

      them after the tree has been

      cut down.

      *

      THAT'S WHY A TREE IS MADE of wood inside. Wood for

      a tree is a bit like your bones are for you. You could

      say that its wood is its skeleton. If you didn't have

      any bones, you'd be floppy like a rag

      doll,

      and you

      wouldn't be able to stand up. The same goes for

      the tree: it needs its wood to stand up straight. And

      because wood is so

      strong,

      it

      can

      support

      a

      tree even

      when it grows really

      tall.

      If you take a look at a tree that's been cut down,

      you'll


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