WEBVTT 00:00.800 --> 00:03.233 position:10% line:85% size:80% JOAN CARTAN-HANSEN, HOST: TREES DO MORE THAN JUST MAKE 00:03.233 --> 00:04.233 position:10% line:85% size:80% OUR WORLD PRETTY. 00:04.233 --> 00:06.800 position:10% line:85% size:80% THEY GIVE US OXYGEN, KEEP OUR AIR CLEAN, PROVIDE HOMES, 00:06.800 --> 00:08.900 position:10% line:85% size:80% FOOD, MEDICINE AND PREVENT EROSION. 00:08.900 --> 00:11.000 position:10% line:85% size:80% FIND OUT MORE ABOUT TREES. 00:11.433 --> 00:14.266 position:10% line:85% size:80% (Music) 00:16.500 --> 00:19.367 position:10% line:85% size:80% >>> WHAT IS THE OLDEST THING ON EARTH? 00:19.367 --> 00:21.333 position:10% line:85% size:80% WHAT IS THE HEAVIEST? 00:21.333 --> 00:23.533 position:10% line:85% size:80% WHAT IS THE TALLEST? 00:23.533 --> 00:26.367 position:10% line:85% size:80% IT'S A TREE. 00:26.367 --> 00:27.700 position:10% line:85% size:80% >> A TREE IS A PLANT. 00:27.700 --> 00:30.633 position:10% line:85% size:80% IT'S A SPECIAL KIND OF PLANT P BECAUSE IT BUILDS UP STRENGTH 00:30.633 --> 00:32.700 position:10% line:85% size:80% BY PRODUCING WOOD. 00:32.700 --> 00:36.900 position:10% line:85% size:80% TREES HAVE FIVE BASIC PARTS: THE ROOTS, THE TRUNK, THE 00:36.900 --> 00:42.166 position:10% line:85% size:80% BRANCHES, THE LEAVES, AND THE FLOWERS OR SEEDS. 00:42.166 --> 00:46.500 position:10% line:85% size:80% >> ROOTS ARE WHAT TREES USE TO COLLECT WATER AND NUTRIENTS. 00:46.500 --> 00:50.500 position:10% line:85% size:80% THEY ALSO SPREAD OUT TO HELP KEEP A TREE STANDING UPRIGHT. 00:50.500 --> 00:53.734 position:10% line:85% size:80% >> ROOTS OF A 150-FOOT TALL TREE STRETCH UNDER THE EARTH 00:53.734 --> 00:57.734 position:10% line:85% size:80% FOR AN AREA THE SIZE OF A SOCCER FIELD. 00:57.734 --> 01:00.900 position:10% line:85% size:80% >> THE TRUNK IS THE TREE'S SUPPORT AND TRANSPORT SYSTEM. 01:00.900 --> 01:03.900 position:10% line:85% size:80% THE CENTER PART OF THE TRUNK IS CALLED THE HEARTWOOD. 01:03.900 --> 01:07.900 position:10% line:85% size:80% IT'S MADE UP OF DEAD CELLS. 01:07.900 --> 01:11.700 position:10% line:85% size:80% THE NEXT LAYER IS THE SAPWOOD, IT CONTAINS A SYSTEM OF TUBES 01:11.700 --> 01:13.734 position:10% line:85% size:80% LIKE STRAWS. 01:13.734 --> 01:20.800 position:10% line:85% size:80% THE NEXT LAYER IS THE CAMBIUM. 01:20.800 --> 01:24.233 position:10% line:85% size:80% IT MAKES NEW SAPWOOD AND NEW BARK EACH YEAR, ALLOWING THE 01:24.233 --> 01:26.233 position:10% line:85% size:80% TREE TO GROW WIDER. 01:26.233 --> 01:29.367 position:10% line:85% size:80% THE OUTSIDE LAYER IS THE TREE'S BARK. 01:29.367 --> 01:32.333 position:10% line:85% size:80% THE OUTER BARK PROTECTS AND INSULATES THE TREE. 01:32.333 --> 01:35.066 position:10% line:85% size:80% THE INNER BARK OR PHYLUM CARRIES SAP OR SUGAR TO THE 01:35.066 --> 01:37.700 position:10% line:85% size:80% LEAVES AND THE REST OF THE TREE. 01:37.700 --> 01:41.166 position:10% line:85% size:80% BARK VARIES A LOT FROM TYPE OF TREE TO TYPE OF TREE. 01:41.166 --> 01:44.700 position:10% line:85% size:80% SOME OF IS SO UNIQUE THAT YOU CAN IDENTIFY THE TREE JUST BY 01:44.700 --> 01:47.533 position:10% line:85% size:80% LOOKING AT THE BARK. 01:47.533 --> 01:52.600 position:10% line:85% size:80% >> YOU CAN TELL HOW OLD A TREE IS BY LOOKING AT ITS TRUNK. 01:52.600 --> 01:56.734 position:10% line:85% size:80% EVERY YEAR A TREE GROWS, IT ADDS A NEW GROWTH RING. 01:56.734 --> 02:00.700 position:10% line:85% size:80% COUNT THE RINGS AND YOU KNOW HOW OLD THE TREE IS. 02:00.700 --> 02:02.734 position:10% line:85% size:80% >> THE WAY A TREE SPREADS ITS BRANCHES DEPENDS UPON ITS 02:02.734 --> 02:04.266 position:10% line:85% size:80% SPECIES. 02:04.266 --> 02:07.700 position:10% line:85% size:80% TREES REACH OUT TO EXPOSE THEIR LEAVES TO THE SUN. 02:07.700 --> 02:10.433 position:10% line:85% size:80% TOGETHER THE BRANCHES AND THE LEAVES OR NEEDLES MAKE UP THE 02:10.433 --> 02:15.066 position:10% line:85% size:80% TREE'S CANOPY AND LIKE YOU, TREES NEED FOOD. 02:15.066 --> 02:19.066 position:10% line:85% size:80% EXCEPT THAT TREES MAKE THEIR OWN FOOD. 02:19.066 --> 02:21.700 position:10% line:85% size:80% THEY USE A PROCESS CALLED PHOTOSYNTHESIS. 02:21.700 --> 02:25.166 position:10% line:85% size:80% WATER AND NUTRIENTS ARE SENT UP FROM THE ROOTS TO THE LEAVES. 02:25.166 --> 02:28.333 position:10% line:85% size:80% THE LEAVES TAKE IN CARBON DIOXIDE FROM THE AIR. 02:28.333 --> 02:31.066 position:10% line:85% size:80% USING ENERGY FROM THE SUN, THE LEAVES COMBINE THE WATER AND 02:31.066 --> 02:34.367 position:10% line:85% size:80% THE CARBON DIOXIDE TO MAKE SUGARS THAT THE TREE USES TO 02:34.367 --> 02:36.000 position:10% line:85% size:80% FEED ITSELF. 02:36.000 --> 02:38.900 position:10% line:85% size:80% AND THEN THE PROCESS, THE LEAVES RELEASE OXYGEN AND WATER 02:38.900 --> 02:41.266 position:10% line:85% size:80% VAPOR INTO THE AIR. 02:41.266 --> 02:43.166 position:10% line:85% size:80% TREES ALSO PRODUCE SEEDS. 02:43.166 --> 02:45.800 position:10% line:85% size:80% MANY TREES PRODUCE A FLOWER THAT'S POLLENATED AND GROWS 02:45.800 --> 02:49.800 position:10% line:85% size:80% SEEDS BUT SOME TREES PRODUCE THE FRUIT WE EAT LIKE APPLES 02:49.800 --> 02:51.433 position:10% line:85% size:80% AND PEARS. 02:51.433 --> 02:54.967 position:10% line:85% size:80% THEIR SEEDS ARE PROTECTED INSIDE THE FRUIT. 02:54.967 --> 02:58.700 position:10% line:85% size:80% >> A PINECONE IS A KIND OF FRUIT. 02:58.700 --> 03:02.000 position:10% line:85% size:80% IT CONTAINS A PINE TREE'S SEEDS. 03:02.000 --> 03:05.633 position:10% line:85% size:80% THE SEEDS ARE DISPERSED BY THE WIND, TAKE ROOT ON THE GROUND 03:05.633 --> 03:08.166 position:10% line:85% size:80% AND START GROWING A NEW TREE. 03:08.166 --> 03:13.066 position:10% line:85% size:80% THERE ARE TWO BASIC KINDS OF TREES, BROAD LEAF AND CONIFER. 03:13.066 --> 03:16.967 position:10% line:85% size:80% BROAD LEAF OR SOMETIMES CALLED DECIDUOUS TREES HAVE LEAVES 03:16.967 --> 03:19.600 position:10% line:85% size:80% THAT BUD OUT IN THE SPRING AND GROW FULL AND LUSH IN THE 03:19.600 --> 03:21.000 position:10% line:85% size:80% SUMMER. 03:21.000 --> 03:23.166 position:10% line:85% size:80% AND THEN THE LEAVES TURN COLOR IN THE AUTUMN AND DROP TO THE 03:23.166 --> 03:24.700 position:10% line:85% size:80% GROUND. 03:24.700 --> 03:28.367 position:10% line:85% size:80% ALMOST ALL CONIFER TREES HAVE DARK GREEN NEEDLES THAT STAY ON 03:28.367 --> 03:30.433 position:10% line:85% size:80% YEAR ROUND. 03:30.433 --> 03:34.633 position:10% line:85% size:80% CONIFER TREES BASICALLY HAVE TWO KINDS OF NEEDLES. 03:34.633 --> 03:36.967 position:10% line:85% size:80% SOME HAVE SHORT NEEDLES THAT LOOK AND KIND OF FEEL LIKE 03:36.967 --> 03:39.100 position:10% line:85% size:80% COMBS. 03:39.100 --> 03:44.000 position:10% line:85% size:80% AND OTHERS HAVE LONG NEEDLES THAT COME IN BUNDLES. 03:44.000 --> 03:46.900 position:10% line:85% size:80% >> ONE KIND OF CONIFER TREE DOES CHANGE COLOR IN THE FALL. 03:46.900 --> 03:49.433 position:10% line:85% size:80% TAMARACKS TURN A BEAUTIFUL YELLOW AND THEN GO BACK TO 03:49.433 --> 03:51.900 position:10% line:85% size:80% GREEN IN THE SPRING. 03:51.900 --> 03:54.000 position:10% line:85% size:80% >> TREES PLAY AN IMPORTANT PART IN THE ENVIRONMENT AND IN OUR 03:54.000 --> 03:55.266 position:10% line:85% size:80% LIVES. 03:55.266 --> 03:57.900 position:10% line:85% size:80% THEY SHADE OUR HOMES, PROTECT OUR SOIL, AND GIVE ANIMALS AND 03:57.900 --> 04:00.367 position:10% line:85% size:80% PEOPLE A PLACE TO LIVE. 04:00.367 --> 04:04.633 position:10% line:85% size:80% WE GET PAPER, LUMBER, MEDICINE, FRUIT, NUTS, EVEN MAPLE SYRUP 04:04.633 --> 04:07.000 position:10% line:85% size:80% FROM TREES. 04:07.000 --> 04:12.800 position:10% line:85% size:80% AN ENVIRONMENTAL -- DEFORESTATION AND OVERCROWDING 04:12.800 --> 04:15.700 position:10% line:85% size:80% CAN HARM TREES AND FORESTS. 04:15.700 --> 04:18.967 position:10% line:85% size:80% TREES ARE VERY GOOD AT ADAPTING TO THE LAND AROUND THEM. 04:18.967 --> 04:21.600 position:10% line:85% size:80% THEY CAN OUTLIVE ALL OTHER VING THINGS. 04:21.600 --> 04:25.066 position:10% line:85% size:80% BUT WE HUMANS NEED TO MAKE SURE WE PROTECT THE AIR, WATER AND 04:25.066 --> 04:27.734 position:10% line:85% size:80% SOIL SO TREES CAN GROW. 04:27.734 --> 04:30.367 position:10% line:85% size:80% AND WE NEED TO PLANT TREES AND TAKE CARE OF OUR FORESTS TO 04:30.367 --> 04:32.233 position:10% line:85% size:80% IMPROVE THE ENVIRONMENT. 04:32.233 --> 04:36.066 position:10% line:85% size:80% TREES ARE ESSENTIAL TO ALL OF US. 04:36.066 --> 04:39.633 position:10% line:85% size:80% IF YOU WANT TO LEARN MORE ABOUT TREES CHECK OUT THE 04:39.633 --> 04:41.266 position:10% line:85% size:80% SCIENCE TREK WEBSITE. 04:41.266 --> 04:44.533 position:10% line:85% size:80% YOU'LL FIND IT AT SCIENCETREK.ORG. 04:45.166 --> 05:00.600 position:10% line:85% size:80% (music) 05:05.600 --> 05:08.166 position:10% line:85% size:80% Narrator: Presentation of Science Trek on Idaho Public 05:08.166 --> 05:11.066 position:10% line:85% size:80% Television is made possible through the generous support 05:11.066 --> 05:14.066 position:10% line:85% size:80% of the Laura Moore Cunningham Foundation, committed to 05:14.066 --> 05:16.800 position:10% line:85% size:80% fulfilling the Moore and Bettis Family legacy of 05:16.800 --> 05:20.266 position:10% line:85% size:80% building the great state of Idaho; by the Idaho National 05:20.266 --> 05:23.700 position:10% line:85% size:80% Laboratory, mentoring talent and finding solutions for 05:23.700 --> 05:27.533 position:10% line:85% size:80% energy and security challenges, by the Friends of 05:27.533 --> 05:31.333 position:10% line:85% size:80% Idaho Public Television and by the Corporation for Public