THEY ARE PRECIOUS PARCELS OF THE MOST COVETED LAND IN THE AMERICAN WEST.

THEY ARE CLASSROOM THE INQUISITIVE AND PLAYGROUND TO THE ADVENTUROUS.

THEY CONTAIN COUNTLESS JEWELS OF THE NATURAL WORLD AND THEY ARE ALL SET IN THE DESERT.

OUR SOUTHWESTERN GEMS, DESERT NATIONAL PARKS.

FUNDING FOR THIS PROGRAM WAS PROVIDED BY DESERT PROGRAM PARTNERS.

♪ MUSIC ♪ ♪ MUSIC ♪ ♪ MUSIC ♪ "THERE IS NOTHING SO AMERICAN AS OUR NATIONAL PARKS...

THE FUNDAMENTAL IDEA BEHIND THE PARKS... IS THAT THE COUNTRY BELONGS TO THE PEOPLE... FOR THE ENRICHMENT OF THE LIVES OF ALL OF US."

WITH THOSE WORDS, PRESIDENT FRANKLIN D. ROOSEVELT PERHAPS BEST DESCRIBED THE INTENT OF THE NATIONAL PARK SYSTEM.

FOR THOSE LIVING IN THE WEST IT COMES AS NO SURPRISE THAT THE ENRICHMENT ROOSEVELT SPOKE OF BEGAN HERE.

IN 1864 YOSEMITE WAS THE FIRST.

THEN CAME YELLOWSTONE.

FOLLOWED LATER BY SEQUOIA AND KING'S CANYON AND OTHERS ALL WEST OF THE ROCKY MOUNTAINS, ALL WIDE-OPEN SPACES.

NOT SURPRISINGLY IN THE LOWER 48 STATES THERE'S NOWHERE MORE WIDE OR OPEN THAN OUR DESERTS WHICH MAKE UP THE VAST MAJORITY OF THE PARKS IN THE SOUTHWEST.

WHETHER AS PARKS OR MONUMENTS OR PRESERVES, DESERT REGIONS HAVE GOOD REASON TO BE PROTECTED.

ONE OF THE CHALLENGES TO ALL OF OUR NATIONAL PARKS IS THE FACT THAT THESE PARKS ARE JUST POSTAGE STAMPS.

BACK EAST THEY'RE SMALL ENOUGH SO THAT FEW OF THE PARKS HAVE LANDSCAPE LEVEL IMPLICATIONS.

OUT WEST WE HAVE LARGER POSTAGE STAMPS AND LARGE ENOUGH TO ACTUALLY CONSERVE PARTS OF SOME ECOSYSTEMS.

THE DIFFERENCE BETWEEN PARKS OUT WEST COMPARED TO OTHER PARTS OF THE COUNTRY EITHER OUT EAST OR FURTHER NORTH PRIMARILY TO ME RELATES TO THE AMOUNT OF PRECIPITATION THEY GET.

SO THE REASON THAT THERE ARE DESERTS AND THE REASON THAT PARKS ARE ESTABLISHED ON TOP OF THOSE DESERTS REALLY MAKE THEM SORT OF UNIQUELY DIFFERENT THAN PROBABLY MOST ANY OTHER PLACE IN THE WORLD.

AND THAT LACK OF PRECIPITATION, WHICH IS TRUE OF MOST OF THE ARID WEST, REALLY HAS IMPORTANT IMPLICATIONS FOR PARKS AND THEIR MANAGEMENT AND THEIR USE.

IT MAKES THEM VERY DIFFERENT THAN EASTERN PARKS.

PRINCIPALLY THAT LIMITED RAINFALL REALLY AFFECTS OVERALL BIOLOGICAL PRODUCTIVITY OF THOSE PLACES, BASICALLY PLANTS GROW MORE SLOWLY SO THEY'RE MORE VULNERABLE TO DISTURBANCES.

THOSE PLANTS, ALONG WITH TOPOGRAPHY, GEOGRAPHY AND CLIMATE, ARE OFTEN USED TO DEFINE A LAND AS DESERT.

BUT NOT ALL DESERTS ARE THE SAME.

THE UNITED STATES ALONE CONTAINS FOUR DISTINCT DESERTS DISTINGUISHED AS GREAT NORTH AMERICAN DESERTS.

THEY ARE THE GREAT BASIN, MOJAVE, SONORAN AND THE CHIHUAHUAN.

WITHIN EACH OF THESE DESERTS ARE EXTRAORDINARY TREASURES DEEMED WORTHY OF FEDERAL PROTECTION.

WHEN YOU LOOK BENEATH THE GREAT BASIN DESERT ON A MAP, YOU'LL SEE PRIMARILY NEVADA, HOME TO GREAT BASIN NATIONAL PARK.

THIS NORTHERNMOST OF THE NORTH AMERICAN DESERTS IS WELL NAMED.

IMPOSING MOUNTAIN RANGES SURROUND THE VALLEY FLOORS CREATING UNDRAINED CATCHMENTS FOR THE PRECIPITATION THAT FALLS THERE.

THE MOISTURE IN THE BASIN IS MINIMAL AND WHAT THERE IS COMES IN EARLY SPRING AND LATE WINTER.

THE GREAT BASIN IS CONSIDERED A COLD DESERT BECAUSE OF THE EXTREME COLD DURING THE WINTER.

BUT IT'S ALSO CONSIDERED A RAIN SHADOW DESERT.

THE STORMS COMING OFF THE PACIFIC, AS THEY SWEEP OVER THE NEVADAS, LOSE MOST OF THEIR MOISTURE AND ON THE BACK SIDE IT'S VERY, VERY DRY AND THAT'S WHERE THE GREAT BASIN IS.

THE DOMINATE PLANT IS BIG SAGE AND YOU FIND JUST TREMENDOUS EXPANSES OF IT.

SOME OF THE ADAPTATION THAT BIG SAGE HAVE ARE TINY LEAVES.

THAT CUTS DOWN ON EVAPORATION.

AND YOU'LL NOTICE THAT THEY'RE KIND OF A SILVERY-GRAY.

THAT'S CAUSED BY TINY HAIRS AND THAT REFLECTS SUNLIGHT SO IT COOLS THE PLANT.

THE STALK AND BRANCHES ARE WOODY SO IT CAN WITHSTAND COLD AND HEAT.

IN THE HEAT OF THE SUMMER TEMPERATURES IN THE GREAT BASIN RISE TO NEARLY 100 DEGREES.

WINTER TEMPERATURES CAN DIP TO MINUS 35 FAHRENHEIT, OUTSIDE THAT IS.

TEMPERATURES INSIDE LEHMANN CAVES WITHIN THE PARK ARE MODERATE ENOUGH FOR IT TO STAY OPEN EVEN THROUGH WINTER.

TO ENJOY THE REST OF THE PARK VISITORS MUST COME IN THE SUMMER.

THE PARK WAS ESTABLISHED ON OCTOBER 27, 1986.

IT WAS ESTABLISHED TO CAPTURE AND PRESERVE FOR FUTURE GENERATIONS A REALLY PRISTINE REMNANT AND PART OF THE GREAT BASIN.

IT'S UNIQUE BECAUSE THE WATER THAT'S PRESERVED IN THE GREAT BASIN IS CAPTURED IN ALL OF THE LOWER VALLEYS.

IT HAS OVER 160 MOUNTAIN RANGES WITHIN THE GREAT BASIN.

WITH THE SIERRA NEVADAS ON THE WESTERN BORDER AND THE SKY ISLANDS ALONG THE EASTERN, NEVADA IS FAMOUS FOR ITS MOUNTAINS.

THE STATE'S SECOND HIGHEST PEAK IS WITHIN THE GREAT BASIN NATIONAL PARK.

BUT THIS SUMMIT DIDN'T HAVE SUCH A LOFTY ORIGIN.

THE LINES IN THESE ROCK REPRESENT LAYERS OF COARSE SAND DEPOSITED IN AN ANCIENT SEAWAY ABOUT 550 MILLION YEARS AGO.

THIS IS THE ROCK THAT NOW CAPS WHEELER PEAK.

MOVEMENTS OF THE CRUST OVER THE LAST 15 MILLION YEARS AND ASSOCIATED EARTHQUAKE ACTIVITY HAVE RESULTED IN ROCKS THAT ORIGINATED BELOW SEA LEVEL NOW STANDING AT 13,000 FEET IN GREAT BASIN NATIONAL PARK.

AS WITH ALL DESERTS, ELEVATION MAKES A SIGNIFICANT DIFFERENCE TO ITS PLANTS.

IN THE SOUTHERN HEMISPHERE SOME ANDEAN DESERTS ACTUALLY GET DRIER THE GREATER THE ALTITUDE RESULTING IN FEWER PLANTS.

HERE IN THE GREAT BASIN IT'S JUST THE OPPOSITE.

DOWN IN THE VALLEY FLOOR YOU CAN GET RAINFALLS LESS THAN 10 INCHES AND AS YOU SWEEP UP THE MOUNTAIN SLOPE IT CAN INCREASE TO UP TO 20, 24 INCHES OF RAINFALL.

WHILE THE VEGETATION AND LANDSCAPE MAY VARY GREATLY, PARK VISITORS SEEM TO BE IN AGREEMENT AS TO THEIR MOTIVATION FOR VISITING GREAT BASIN NATIONAL PARK.

99.9% OF ALL THE VISITORS THAT I'VE CONTACTED IN THE PARK ARE PEOPLE LIKE YOU AND ME WHO ARE HERE JUST FOR SOLITUDE AND TO APPRECIATE THE VALUE OF WHAT THIS PARK HAS TO OFFER IN ITS BEAUTY, IN ITS SCENERY, IN ITS SIGHTS AND SMELLS.

IT'S JUST SO DIVERSE.

ALONG THE EASTERN EDGE OF THE GREAT BASIN DESERT IS A TINY SPOT MARKING AN ESPECIALLY CONCENTRATED COLLECTION.

...SO THESE COULD BE COOLING OR HEATING PLATES.

IF IT'S TOO COLD, THEY CAN HOLD THOSE PERPENDICULAR TO THE SUN AND WARM THEMSELVES UP.

WHAT'S GATHERED HERE ARE CREATURES, PREVIOUS INHABITANTS FROM HUNDREDS OF MILLIONS OF YEARS AGO.

IT'S DINOSAUR NATIONAL MONUMENT.

THE MONUMENT WAS ESTABLISHED BECAUSE OF ITS EXTRAORDINARY REMAINS OF DINOSAURS FROM THE JURASSIC PERIOD.

IT'S A TREMENDOUS CONCENTRATION OF LARGE ANIMALS, 145, 150 MILLION YEAR OLD DINOSAURS.

THE FOSSIL BONES THAT WE HAVE AT THE QUARRY HERE ARE NOT FOSSILIZED IN THE SAME WAY THAT YOU SEE IN A PIECE OF PETRIFIED WOOD WHERE THE ENTIRE PLANT HAS BEEN REPLACED BY MINERALS.

THE ACTUAL BONE THAT THESE DINOSAURS USED IN THEIR LIFE IS PRETTY MUCH PRESENT STILL IN THESE FOSSILS.

CAN YOU IMAGINE DISCOVERING THIS FOR THE FIRST TIME?

I MEAN, YOU WOULD JUST SCREAM IN DELIGHT.

IT WOULD BE SO WONDROUS.

THERE HAVE BEEN MORE DINOSAURS, NEW DINOSAURS DISCOVERED IN THE LAST 10, 20 YEARS THAN IN ALL OF THE DECADES PRIOR TO THAT.

THIS IS A NEW SPECIES OF ALLOSAURUS, ONE OF THESE LARGE CARNIVOROUS DINOSAURS FROM THE JURASSIC PERIOD AND THIS IS A PARTICULARLY EXCEPTIONAL SPECIMEN BECAUSE ALMOST THE ENTIRE ANIMAL IS PRESERVED.

THERE ARE OTHER PLACES IN THE WORLD WHERE YOU HAVE CONCENTRATIONS OF BONES LIKE THIS BUT FOR LARGE DINOSAURS THIS IS PARTICULARLY WEALTHY.

YES, SIR CAN I HELP YOU?

WELL, THAT'S WHAT I'M HERE FOR.

I THINK MAYBE YOU CAN.

SANDWICHED BETWEEN THE COLD GREAT BASIN AND THE HOT SONORAN IS THE MOJAVE DESERT, THE SMALLEST OF THE GREAT NORTH AMERICAN DESERTS.

THE VEGETATION IS DESCRIBED AS DESERT SCRUB WITH A MIXTURE OF SHRUBS LIKE CREOSOTE, SAGEBRUSH, BRITTLE BUSH, A FEW CACTI AND THE JOSHUA TREE.

MUCH OF THE MOJAVE RECEIVES LESS THAN THREE INCHES OF MOISTURE A YEAR FALLING MOSTLY IN THE WINTER AND ON RARE OCCASIONS AS SNOW.

A LAND OF EXTREMES, THE MOJAVE DESERT CONTAINS THE SITE OF BOTH THE HOTTEST TEMPERATURE, 134 DEGREES, AND LOWEST ELEVATION IN NORTH AMERICA.

BAD WATER BASIN IN DEATH VALLEY NATIONAL PARK IS 282 FEET BELOW SEA LEVEL.

SEEMINGLY INHOSPITABLE, DEATH VALLEY WAS ACTUALLY ONCE FULL OF LIFE.

THERE WERE PREHISTORIC NATIVE TRIBES THAT WERE HERE WHEN MOST OF DEATH VALLEY FLOOR WAS A FRESH WATER LAKE AND THEIR TRIBES BASICALLY SURVIVED AROUND THESE LAKES.

ABOUT 10,000 YEARS AGO WHAT WE NOW TERM LAKE MANLEY BEGAN TO DRY UP AND PROBABLY WAS JUST BASICALLY A SMALLER LAKE HERE.

AND THAT'S WHEN TODAY'S MODERN SHOSHONE TRIBES STARTED TO SHOW UP IN THE DEATH VALLEY REGION.

AND THE SHOSHONE TRIBES HAVE BEEN HERE EVER SINCE.

THEY'VE USED THE VALLEY FLOOR AS THEIR WINTER HOME AND HAVE USED THE PANAMINT MOUNTAINS AND THE OTHER MOUNTAINS LIKE THE FUNERALS AND THE BLACKS FOR THEIR SUMMER HOMES TO GET UP OUT OF THE HEAT.

AND THEY LEARNED TO LIVE ON THE LAND AND USE THE LAND AS THEIR HOME FOR MANY YEARS UNTIL 1849 AND THAT'S WHEN THE FIRST EUROPEAN GOLD SEEKERS HEADING FOR CALIFORNIA STUMBLED INTO THIS AREA.

MOST OF THE HUMAN HISTORY FROM PROBABLY THAT 1860 TIL 1933 WHEN DEATH VALLEY NATIONAL MONUMENT WAS SET ASIDE THIS WAS A MINING HEAVEN.

THIS IS WHERE PEOPLE CAME TO SEARCH OUT THEIR RICHES.

THERE WERE MINING COMPANIES, THERE WERE A LOT OF FOLKS THAT WERE SPECULATING ON THE MINING MARKET AND THEN THERE WERE THOSE THAT WERE JUST YOUR GOOD OLD PROSPECTOR.

WHEN THE MONUMENT WAS ESTABLISHED IN 1933 TO SET ASIDE THE AREA AS A NATIONAL MONUMENT FOR ITS PROTECTION, ONE OF THE CLAUSES WAS THAT THEY WOULD ALLOW CURRENT MINING TO CONTINUE.

SO UNTIL ACTUALLY 1970 PEOPLE COULD STILL COME TO DEATH VALLEY AND LAY A MINING CLAIM.

THIS WAS A NATIONAL MONUMENT.

AND THAT'S ONE OF THE BIG HOLD UPS FROM MAKING IT A NATIONAL PARK.

EVENTUALLY IN 1970 LEGISLATION WAS PASSED THAT CURTAILED ANY NEW MINING CLAIMS IN THE MONUMENT.

DEATH VALLEY BECAME A NATIONAL PARK IN 1994 MAKING IT THE LARGEST NATIONAL PARK SOUTH OF CANADA.

IT IS ONE OF MANY NATIONAL PARKS ESTABLISHED FOR ITS GEOLOGICAL RICHNESS.

IF YOU GO FROM 11,000 DOWN TO BELOW SEA LEVEL IN ABOUT A HORIZONTAL DISTANCE OF 14 MILES YOU HAVE SOME OF THE GREATEST RELIEF IN THE NORTH AMERICAN CONTINENT AND ON THE EARTH AS WELL.

SO THIS IS A SPECTACULAR VIEW OF THAT RELIEF AND OF SOME OF THE REALLY SPECIAL FEATURES, GEOLOGIC AND NATURAL HISTORY FEATURES THAT YOU FIND IN DEATH VALLEY WITHIN THE MOJAVE DESERT.

WAY OFF IN THE DISTANCE, BARELY VISIBLE, AT THE FAR END OF THE VALLEY ARE THE SAND DUNES AND YOU CAN BARELY SEE LITTLE HUMPS AND BUMPS OUT THERE THAT REPRESENT THE STAR DUNES AND TRANSVERSE DUNES THAT ARE PART OF THE MESQUITE DUNES.

LOOKING DOWN FROM DANTE'S VIEW ONE SEES A SPRAWLING LANDSCAPE OF OMINOUSLY NAMED COMPONENTS, LIKE FUNERAL PAK, BAD WATER, FURNACE CREEK AND THE DEVIL'S GOLF COURSE.

BY COMPARISON, MESQUITE FLATS SOUNDS DOWNRIGHT WELCOMING.

WHEN ONE THINKS OF A DESERT, ONE USUALLY PICTURES A VAST EXPANSE OF SAND SIMILAR TO THE DUNES HERE AT MESQUITE FLAT IN THE CENTER OF DEATH VALLEY.

IN FACT, THESE DUNES ONLY COVER A VERY SMALL PORTION OF ONE OF THE DRIEST AND HOTTEST PLACES IN NORTH AMERICA.

AND THAT'S TYPICAL OF DESERTS OF THE WORLD.

SAND DUNES MAY ACTUALLY COVER ABOUT 20% OF THE TOTAL DESERT AREAS THAT WE KNOW ON EARTH.

SAND DUNES FORM WHEN YOU GET PERSISTENT AND STRONG ENOUGH WINDS TO PICK UP, TRANSPORT AND COLLECT THE SAND GRAINS IN ONE AREA.

THE CONGREGATION OF SAND GRAINS INTO DUNES PROVIDES A CANVAS.

THE PAINTERS ARE THE NATIVE CRITTERS AND THE IMPRESSIONS THEY LEAVE ARE SIMPLY THE TRACINGS OF THEIR NORMAL ACTIVITY.

MOST OF THE ANIMALS THAT OCCUR IN THE DUNE AREAS ARE TYPICALLY NOCTURNAL.

THEY COME OUT AT NIGHT BECAUSE DURING THE DAY THE DUNES ARE SO HOT, THE SUN IS SO INTENSE.

BUT THEY LEAVE EVIDENCE OF THEM BEING THERE, ESPECIALLY TRACKS.

YOU'LL SEE ALL KINDS OF TRACKS OVER THE DUNES.

THERE'S DESERT KANGAROO RAT.

THERE'S KIT FOX.

YOU'LL SEE LIZARDS AND BEETLE TRACKS AS WELL.

THOSE TWO ARE PRIMARILY ACTIVE DURING THE DAY BUT THE OTHERS ARE ACTIVE MOSTLY AT NIGHT.

TO EXPERIENCE ISOLATED DEATH VALLEY, MOST VISITORS TRAVEL VAST DISTANCES.

BY CONTRAST, JOSHUA TREE, THE MOJAVE DESERT'S OTHER FULL-FLEDGED NATIONAL PARK IS A MERE COUPLE HOURS DRIVE FOR THE 18 MILLION PEOPLE LIVING IN POPULOUS SOUTHERN CALIFORNIA.

THE NAME SAKE JOSHUA TREE IS A MOJAVE DESERT ICON.

MOST PEOPLE WHEN THEY THINK OF THE MOJAVE DESERT THEY THINK OF THE JOSHUA TREE AND SO YES IT IS THE SIGNATURE PLANT OF THAT PARTICULAR REGION.

BUT I SHOULD POINT OUT THAT THEY ARE FOUND IN SOME OTHER ENVIRONMENTS AS WELL BUT ALL OF THOSE ENVIRONMENTS ARE IMMEDIATELY ADJACENT AND CLOSELY ASSOCIATED WITH THE MOJAVE DESERT.

JOSHUA TREES START OUT LIFE AS A SMALL, BLACK SEED, VERY THIN AND MAYBE A QUARTER OF AN INCH IN DIAMETER.

THOSE SEEDS GERMINATE VERY READILY.

AS SOON AS THEY GET TEMPERATURES OVER 60 DEGREES FAHRENHEIT AND IF THEY'RE IN MOIST CONDITIONS, THEY WILL GERMINATE ALMOST 100% OF THE TIME.

THOSE SMALL TREES ARE USUALLY EATEN BY PREDATORS AND MAYBE ONLY ONE OUT OF A HUNDRED, MAYBE ONE OUT OF A THOUSAND ACTUALLY SURVIVE TO GROW TO BE EIGHT TO TEN INCHES TALL.

THE TIME IT TAKES FROM SEEDLING GERMINATION TO MATURITY IS AT LEAST 40 YEARS AND PROBABLY MORE ON THE ORDER OF 50 TO 60 YEARS.

OUR BEST ESTIMATES ARE THE JOSHUA TREES LIVES ABOUT 150 YEARS ON AVERAGE AND I SAY ON AVERAGE BECAUSE THERE'S CERTAINLY SOME TREES THAT LIVE MAYBE 500 OR 600 YEARS.

JOSHUA TREE GOT ITS NAME BY THE EARLY MORMON PIONEERS THAT WERE TRAVELING FROM SALT LAKE CITY INTO SOUTHERN CALIFORNIA TO SETTLE AND WHEN THEY SAW THE JOSHUA TREES THEY KNEW THAT THEIR JOURNEY WAS HALF WAY DONE.

CONSEQUENTLY THEY FELT, PARTICULARLY FROM A DISTANCE WITH THEIR BRANCHES AND THEIR RELATIVELY HUMAN-LIKE APPEARANCE FROM A DISTANCE, THEY FELT THAT THE JOSHUA TREE RESEMBLED THE BIBLICAL JOSHUA AND CONSEQUENTLY NAMED THE TREE AFTER JOSHUA.

LONG BEFORE THE MORMONS CAME, NATIVE SOCIETIES FLOURISHED AND THEN FAILED THROUGHOUT THE WEST, LARGELY DUE TO THE AVAILABILITY OF WATER.

TOWERING ABOVE THE MOJAVE DESERT FLOOR, JUST TO THE EAST OF DEATH VALLEY, IS SEQUOIA NATIONAL PARK.

THE STORY OF DROUGHT AND WITH IT THE RISE AND FALL OF CIVILIZATIONS UNFOLDS INSIDE THESE NAMESAKE BEAUTIES.

THE SEQUOIAS ARE THE WORLD'S LARGEST LIVING TREES BY VOLUME AND THEY'RE AMONG THE TALLEST TREES IN THE WORLD AS WELL.

AND THEY'RE ALSO AMONG THE OLDEST TREES IN THE WORLD.

THE OLDEST KNOWN SEQUOIA WE KNOW ABOUT IS ABOUT 3,200 YEARS AND WE KNOW THAT BECAUSE IT WAS CUT DOWN UNFORTUNATELY ABOUT 100 YEARS AGO.

SEQUOIAS HAVE A PRETTY EVEN RING GROWTH.

THE RINGS ARE ALMOST ALL THE SAME YEAR AFTER YEAR AFTER YEAR UNTIL YOU GET INTO ONE OF THESE REALLY MAJOR DROUGHT YEARS AND THEN IT FORMS A VERY TINY RING.

AND SO SEQUOIAS ARE KIND OF LIKE AN EVENT RECORDER WHEN IT COMES TO DROUGHTS.

WHAT'S SHOWN HERE WITH THIS NEEDLE IS THE 1580 RING.

THIS IS THE SMALLEST RING IN THE ENTIRE 3,200 YEAR LONG GIANT SEQUOIA RING RECORD AND IT CORRELATES WITH AN EXTREME DROUGHT THAT OCCURRED HERE IN CALIFORNIA AND IN FACT ALL ACROSS THE NORTH AMERICAN CONTINENT FROM THE CALIFORNIAS ALL THE WAY OVER TO THE CAROLINAS.

SO THIS HAS BECOME KNOWN AS THE 1580S MEGA DROUGHT AND IT HAD VERY SEVERE IMPACTS ON ECOSYSTEMS AND THE CULTURES THAT LIVED HERE IN THE WESTERN U.S. AND IN NORTHERN MEXICO AND ACROSS THE SOUTHEAST.

THIS DROUGHT IMPACTED PEOPLE AS WELL AS ECOSYSTEMS.

MANY OF THE OVER ONE MILLION ANNUAL VISITORS TO SEQUOIA AND KING'S CANYON NATIONAL PARKS MISS THE SIGNIFICANCE OF THE MINUTE DIFFERENCES IN THE TREE'S GROWTH RINGS.

THEY COME FOR THE SPECTACLE OF THE FOREST, AND A GRAND ONE IT IS.

FOR THAT THRILL ALONE, A LARGE DEBT OF GRATITUDE IS OWED TO JOHN MUIR, THE RENOWNED NATURALIST.

IN 1873 MUIR VISITED THE SEQUOIAS AND NOTICED THAT LUMBER MILLS HAD CUT DOWN ALL THE MATURE, MAJESTIC TREES EXCEPT ONE.

AFTER A TOUGH LOBBYING FIGHT THE PARK WAS ESTABLISHED AND TO THIS DAY EXEMPLIFIES SOME OF THE NATIONAL PARK SERVICES MOST DIFFICULT ISSUES.

THE ROLE OF NATIONAL PARKS HAS CHANGED OVER TIME WHICH IS FUN TO THINK ABOUT.

ORIGINALLY THEY WERE ESTABLISHED PRINCIPALLY FOR PRESERVATION KINDS OF IDEAS AND THERE WERE SOME CHALLENGES TO THAT IDEAL FROM SORT OF THE STRICT PRESERVATIONIST JOHN MUIR KIND OF PERSPECTIVE TO ONE OF THOSE CHALLENGING IT FOR UTILITARIAN REASONS.

SO THE PARK SERVICE HAS REALLY CHANGED IN THEIR VIEW AND ROLE IN A BUNCH OF WAYS AND PRINCIPALLY ONE IS STRIKING THAT SORT OF DIFFICULT BALANCE BETWEEN PRESERVATION AND UTILITARIAN USE.

MANAGERS AT THE PARKS I THINK ARE CHALLENGED IN A REALLY INTERESTING WAY IN THAT THEY'RE TRYING TO BALANCE THIS PRESERVATIONIST SORT OF AESTHETIC WITH "COME ON DOWN AND SEE OUR PARKS AND USE THEM AND ENJOY THEM AND LEARN ABOUT THAT," SO THIS TWISTED CONSERVATION AND DEVELOPMENT REALLY MAKES MANAGING PARKS MORE DIFFICULT THAN SOME OTHER KINDS OF LANDS WHERE I THINK THE MANDATES ARE A LITTLE BIT MORE CLEAR.

GETTING THE VISITORS TO COME TO A NATIONAL PARK DOESN'T ALWAYS HAVE TO DO SOLELY WITH THE NATURAL BEAUTY OF THE PARK.

IT'S ALSO A MATTER OF ACCESSIBILITY.

BIG BEND NATIONAL PARK LIES IN THE NORTHERN SECTION OF THE CHIHUAHUAN DESERT AND IT'S A LONG WAY FROM ANYWHERE.

I THINK THE VISITORS WHO COME TO BIG BEND NATIONAL PARK ARE DIFFERENT FROM A LOT OF NATIONAL PARKS THAT ARE CLOSER TO URBAN AREAS.

THEY REALLY HAVE TO WANT TO GET HERE.

IT'S NOT ON THE ROAD TO ANYWHERE.

IF THEY COME HERE FOR THE FIRST TIME, I THINK THEY'RE IN AWE AND SOMETIMES MAYBE A LITTLE AFRAID OF WHAT THEY'RE SEEING BECAUSE IT IS SO AWESOME, SO LARGE AND DIFFERENT FROM MOST OF THE PLACES WHERE THEY COME FROM.

IT'S DIFFERENT FROM MOST OF TEXAS AND WE LIKE TO TRY TO BREAK IT DOWN FOR PEOPLE TO MAKE THEM UNDERSTAND IT AND APPRECIATE IT MORE BY SAYING YOU CAN IMAGINE IT AS THREE PARKS IN ONE.

WE'VE GOT THE RIO GRANDE, WE'VE GOT THE DESERT AND WE'VE GOT THE MOUNTAINS.

THE RIO GRANDE RIVER, THE INTERNATIONAL BORDER, IS WHERE THE PARK GETS ITS NAME.

THE RIVER MAKES A SIGNIFICANT TURN, A "BIG BEND" AS IT SLICES THROUGH THE CHIHUAHUAN DESERT, MOST OF WHICH IS IN MEXICO.

TREES ARE RARE IN THIS DESERT.

SHRUBS AND LEAFY SUCCULENTS DOMINATE THE LANDSCAPE ALONG WITH SOME CACTI, ALL OF WHICH MUST COPE WITH MANY FREEZING WINTER NIGHTS FOLLOWED BY A BLAZING SUMMER.

THERE'S NEVER MUCH RAIN AND WHAT DOES FALL IS MOSTLY AFTER MID SUMMER BUT IT'S ENOUGH FOR THESE DESERT PLANTS.

FOLLOWING A GREAT RAIN YEAR THE CHIHUAHUAN DESERT, ESPECIALLY WHAT WE SEE HERE IN BIG BEND NATIONAL PARK CAN JUST BREAK INTO A PROFUSION OF FLOWER BLOSSOMS.

AND WE'VE SEEN NUMEROUS SPECIES.

THERE'S THE LUPINE SOMETIMES CALLED A TEXAS BLUE BONNET.

THERE'S BLADDER POD MUSTARDS, THERE'S DIFFERENT ASTERS.

THE VERBENA SOMETIMES REFERRED TO AS THE SWEET WILLIAMS.

SOME OF THE SHRUBS LIKE THE TEXAS RANGER ARE BLOOMING PROFUSELY.

THE SEEDS CAN BE IN THE SOIL FOR YEARS AND YEARS AND THEN YOU GET THE RIGHT CONDITIONS, RAINFALL CONDITIONS, AND THOSE SEEDS WILL SPROUT AND WHAT USED TO BE BARE GROUND NOW IS JUST COVERED WITH A CARPET OF FLOWERS.

THE YUCCA THAT WE FIND FLOWERING IN THIS AREA RIGHT NOW IS THE SPANISH DAGGER YUCCA.

IT'S ONE OF THE LARGEST OF THE YUCCAS AND IT MUST HAVE BEEN A GOOD RAIN YEAR FOR THEM BECAUSE ALMOST EVERY YUCCA WE SEE HERE IS IN FLOWER RIGHT NOW.

THE YUCCA DEFINITELY IS AN ICON OF THE CHIHUAHUAN DESERT.

THE AMOUNT OF FEDERALLY OWNED LAND IN TEXAS IS PRETTY SMALL COMPARED TO THE REST OF THE WEST.

NEARLY 85 PERCENT OF NEVADA IS FEDERAL PROPERTY.

HERE, IT'S LESS THAN TWO PERCENT BUT THOSE LANDS ENCOMPASS GUADALUPE MOUNTAINS NATIONAL PARK.

WHEN THE STATE OF TEXAS WAS FORMED, ALL THE LAND WAS PRIVATELY OWNED FOR A VARIETY OF REASONS.

SO WHEN THIS PARK WAS ESTABLISHED IT HAD TO BE PURCHASED FROM THE RANCHER THAT RAN IT.

THIS PARK ESTABLISHED IN 1972 AT ABOUT THE SAME TIME REDWOODS WAS ADDED TO THE NATIONAL PARK SYSTEM REPRESENT THOSE LAST PARKS ESTABLISHED FOR THOSE GRAND OLD SCENIC VALUES AND GREAT VISTA VALUES.

AND THEN IN 1998 WE ADDED 10,000 ACRES ON THE WEST SIDE, THE GYPSUM DUNES THAT ARE VERY SIMILAR TO THE WHITE SAND DUNE.

WELL, WE GET VERY LITTLE RAINFALL OUT HERE AND SO A LOT OF THE ANIMALS AND PLANTS COLLECT MOISTURE EITHER FROM WHAT LITTLE DEW CONDENSES ON LEAVES.

THEY GET THEIR MOISTURE REQUIREMENT FROM EATING GREEN VEGETAL MATERIAL.

THE SAND ITSELF STORES MOISTURE IN THE GROUND.

MANY OF THESE PLANTS HAVE A DEEP ROOT SYSTEM THAT WILL WICK MOISTURE UP TO THE SURFACE.

SMALL MAMMALS WILL EAT ON ROOTS.

INSECTS WILL EAT ON ROOTS OR LEAVES.

THIS LITTLE KANGAROO RAT, THE MIRIAM'S KANGAROO RAT, IS ADAPTED TO THE DUNE AREA AND THIS GUY'S A REAL DESERT SURVIVOR.

IT CAN GO ALL ITS LIFE WITHOUT A DROP OF WATER TO DRINK.

IT HAS EXTERNAL CHEEK POUCHES.

THAT WAY IT CAN GATHER THE SEEDS AND STORE THEM AS IT'S FORAGING WITHOUT OPENING ITS MOUTH AND LOSING MOISTURE.

BI-PEDAL, WHICH MEANS IT HOPS AROUND ON ITS HIND LEGS JUST LIKE A KANGAROO.

THAT'S WHERE IT GETS ITS NAME.

THEY'RE CUTE LITTLE GUYS.

NOCTURNAL, YOU CAN SEE THOSE HUGE EYES SO IT CAN SEE WELL AT NIGHT.

IT'S DIFFICULT TO TRAVEL AROUND IN THIS SAND BECAUSE IT GIVES AND THESE ANIMALS HAVE LONG HAIRS ON THEIR TOES AND THEY CAN SPREAD THE FEET AND THESE ACT LIKE SNOWSHOES EXCEPT THESE ARE SAND SHOES AND IT GIVES MORE SURFACE AREA SO THEY DON'T SINK INTO THE SAND.

THE SAND DUNES MAKE UP JUST A SMALL PORTION OF THE PARK WHO'S DOMINATE FEATURE IS MOUNTAINS.

GUADALUPE PEAK IS THE TALLEST PLACE IN TEXAS.

ONE OF THE THINGS THAT'S REALLY, REALLY SPECIAL ABOUT GUADALUPE IS THE WILDERNESS VALUES IN IT.

IT'S PRIMARILY A BACK COUNTRY WILDERNESS PARK.

SO IT'S ONE OF THE FEW PLACES IN TEXAS AND IN THIS AREA WHERE PEOPLE CAN COME AND EASILY INTO SOME REALLY, REALLY GREAT WILDERNESS.

I SOMETIMES JOKE WHEN I TELL PEOPLE ABOUT LIVING OUT HERE IN WEST TEXAS AND THOSE SAND DUNES AND THIS MOUNTAIN RANGE.

I SAY, "IT'S NOT THE END OF THE EARTH BUT YOU CAN SEE IT FROM HERE."

ANOTHER PLACE YOU CAN JUST ABOUT SEE FROM HERE IS WHITE SANDS NATIONAL MONUMENT IN NEW MEXICO, HOME OF THE LARGEST GYPSUM DUNE FIELD IN THE WORLD.

LOCATED IN THE TULAROSA BASIN, IT'S AT THE VERY NORTHERN END OF THE CHIHUAHUAN DESERT.

THE TRULY WHITE SAND IS ESPECIALLY BRIGHT AND ACTUALLY QUITE RARE.

GYPSUM EASILY DISSOLVES IN WATER.

MOST SAND DUNES ARE MADE OUT OF QUARTZ SAND WHICH IS QUITE HARD AND DURABLE.

GYPSUM SAND IS MUCH SOFTER.

IT BREAKS DOWN MUCH MORE EASILY AND EVENTUALLY CAN BREAK DOWN INTO DUST AND BE BLOWN AWAY AND MOVED OUTSIDE THE NUCLEI.

THE SAND COMES FROM A DRY LAKE BED, AN EPHEMERAL LAKE CALLED LAKE LUCERO.

IT'S SOUTHWEST OF THE MAIN DUNE FIELD.

IN LAKE LUCERO GYPSUM CRYSTALS ARE CREATED WHICH EVENTUALLY BREAK DOWN INTO SMALL ENOUGH PARTICLES TO BE MOVED BY THE WIND.

THE DOMINANT WINDS THAT WE HAVE IN THIS AREA ARE DURING THE SPRING.

THEY COME FROM THE WEST AND SOUTHWEST AND THEY BLOW ACROSS LAKE LUCERO AND PICK UP THE PIECES OF CRYSTAL, SAND-SIZE PIECES, AND BLOW THEM TO THE EAST AND OVER THE LAST SEVERAL THOUSAND YEARS HAVE MOVED THEM ABOUT HALFWAY ACROSS THE TULAROSA BASIN.

PEOPLE FIRST CAME TO THE SHORES OF LAKE LUCERO IN THE SOUTHWEST CORNER OF THE MONUMENT 10,000 YEARS AGO.

AFTER ABOUT A THOUSAND YEARS THE REGION BECAME MUCH MORE ARID AND THE LAKES AND LUSH GRASSLANDS DISAPPEARED.

BUT PEOPLE DIDN'T.

THEY HAVE LIVED HERE SEASONALLY EVER SINCE.

IN COLORADO, MORE THAN 400 MILES DIRECTLY NORTH OF WHITE SANDS, IS ANOTHER MONUMENT TO SAND AND NOT JUST SAND OF COURSE, SPECIAL SAND IN NEED OF PROTECTION.

THIS IS GREAT SAND DUNES NATIONAL PARK.

THE MONUMENT WAS ESTABLISHED BACK IN 1933 BY PRESIDENT HERBERT HOOVER ON ST. PATRICK'S DAY.

IT WAS ESTABLISHED BECAUSE WE HAPPEN TO HAVE THE TALLEST DUNES IN NORTH AMERICA AND IT WAS FELT THAT WE SHOULD PRESERVE THEM AND NOT CART THEM AWAY OR MAKE SAND CASTLES OR GLASS OUT OF THEM.

PEOPLE ARE ALWAYS AMAZED TO SAY, "THE TALLEST DUNES IN NORTH AMERICA AND THEY'RE NOT ON A BEACH AND THEY'RE NOT OUT IN THE OPEN.

THEY'RE UP HERE IN THE MOUNTAINS.

HOW CAN THAT BE?"

THESE MOUNTAINS ACT LIKE A BIG SNOW FENCE A KEEP THE SAND FROM BLOWING ALL OVER EASTERN COLORADO IS BASICALLY WHAT HAPPENS HERE.

AND THE CREEKS ARE LIKE FENCES THAT HOLD THE DUNES, THE MAIN DUNE MASS INTO PLACE.

THERE'S ONE ON EITHER SIDE OF THE DUNES AND THE RIVERS CRADLE THE DUNE FIELD AND ACT AS KIND OF A FENCE TO KEEP THE SAND IN PLACE AND THE UNDERWATER WATER TABLE HELPS THE WHOLE SYSTEM.

THE SAND COMES DOWN IN THE CREEKS AND GETS RECYCLED, GETS BLOWN BACK UP INTO THE DUNES AND THEN OF COURSE IT FALLS BACK DOWN INTO THE CREEK EVENTUALLY, COMES AND WASH DOWN AND THEN THE WHOLE CYCLE GOES OVER AND OVER AGAIN.

I WOULD DESCRIBE THIS AS COLORADO'S BEACH.

OFTEN PEOPLE CALL IT THAT.

WE HAVE LOTS OF SAND.

WE DON'T HAVE A LOT OF WATER BUT WE HAVE ENOUGH TO PLAY IN AND WE HAVE WAVES AND THAT MAKES IT A FUN PLACE FOR EVERYBODY.

NOT CONTENT WITH SIMPLE NAMES FOR THE PATCHWORK OF DESERTS SCATTERED ACROSS NORTH AMERICA, BIOLOGISTS AND THEIR OTHER -OLOGIST BRETHREN HAVE COME UP WITH NUMEROUS SUBSETS.

THESE NAMES ARE CHOSEN FOR THE PARTICULAR BIOLOGICAL AND GEOLOGICAL COMPONENTS OF INTEREST TO THE EXPERTS.

NOT SURPRISINGLY, THERE ARE PLENTY OF DISAGREEMENTS ON THE DISTINCTIONS.

THERE'S THE CALIFORNIA DESERT IN THE SOUTHERN MOJAVE, THE ESCALANTE PORTION OF THE GREAT BASIN, THE PAINTED DESERT AND MOST NOTABLY THE COLORADO OR COLORADO PLATEAU DESERT.

IT'S HERE THAT THE NATIONAL PARK SYSTEM HAS COLLECTED SOME OF ITS GRANDEST DESERT GEMS.

ON THE EASTERN EDGE OF THIS DESERT IS CHACO CULTURE NATIONAL HISTORIC PARK.

CHACO CANYON, ITS NAMESAKE, IS THE MAJOR DRAW FOR VISITORS.

CHACO IS A VERY SPECIAL PLACE.

IT'S SPECIAL NOT ONLY NOW FOR THE MANY PEOPLE WHO COME HERE TO VISIT IT AND EXPERIENCE IT BUT IT WAS ALSO A VERY SPECIAL PLACE FOR THE PREHISTORIC ANASAZI WHO LIVED HERE A THOUSAND YEARS AGO.

ACTUALLY CHACO WAS OCCUPIED FROM AS EARLY AS 500 B.C.

BUT THE MAJOR OCCUPATION THAT WE SEE IN CHACO, THE VERY LARGE SITES THAT WE SEE IN CHACO, BASICALLY DATE FROM ABOUT A.D. 800 TO A.D. 1200.

IT WAS ALMOST CERTAINLY ABANDONED BECAUSE OF A DROUGHT.

DURING THE PEAK OF THIS CIVILIZATION, AFTER THE TURN OF THE FIRST MILLENNIUM, CHACO WAS THE CEREMONIAL, ECONOMIC AND ADMINISTRATIVE CENTER FOR THE MANY CLANS WITHIN HUNDREDS OF MILES.

PETRIFIED FOREST NATIONAL PARK WAS ESTABLISHED AS A MONUMENT IN 1906 TO PRESERVE ITS RICHLY COLORFUL PETRIFIED FOOD.

THIS WAS SIX YEARS BEFORE ARIZONA WOULD BECOME A STATE.

SEVERAL PRESIDENTS PREEMPTIVELY ESTABLISHED MONUMENTS IN TERRITORIES UNABLE TO INSTITUTE PROTECTION ON THEIR OWN.

THE CUMULATION OF PETRIFIED WOOD IN THE PARK IS ONE OF THE LARGEST IN THE WORLD.

IN 1963 THE LEFT DIVERSION TUNNEL INSIDE GLEN CANYON DAM WAS CLOSED AND SO BEGAN THE FLOODING OF ONE OF THE MOST SPECTACULAR REGIONS OF THE COLORADO DESERT.

NEARLY A DECADE LATER, GLEN CANYON NATIONAL RECREATION AREA WAS ESTABLISHED AND CONTAINS ALL OF LAKE POWELL.

THE PRIMARY PURPOSE OF GLEN CANYON DAM IS ACTUALLY FOR THE STORAGE OF WATER, IRRIGATION WATER, FOR DELIVERY DOWN TO THE LOWER BASIN STATES.

AS FAR AS THE BENEFITS OF THE DAM, OF COURSE YOU HAVE IRRIGATION, THE PRIMARY PURPOSE, AND THEN A COUPLE OF THE SECONDARY BENEFITS FROM THAT IS POWER GENERATION AND RECREATION.

WE DO USE THE WATER THAT WE RELEASE THROUGH THE DAM FOR POWER GENERATION.

THAT'S HOW WE PRIMARILY RELEASE THE WATER THROUGH HERE.

WHAT COVERS THE NOW SUBMERGED GLEN CANYON PROVIDES AQUATIC AS WELL AS TERRESTRIAL ENJOYMENT FOR ITS VISITORS.

THE KEY WORD USED TO DESCRIBE THE GRAND CANYON PARASHANT NATIONAL MONUMENT IS REMOTE.

WITH A MIX OF MOSTLY MOJAVE DESERT VEGETATION, THIS MILLION ACRE MONUMENT HAS NO FACILITIES OR SERVICES OR VISITATION FEES FOR THAT MATTER.

BUT IT DOES PROVIDE ACCESS TO SOME SPECTACULAR SCENERY WITH BREATHTAKING VISTAS OF ITS MOST FAMOUS NEIGHBOR, GRAND CANYON NATIONAL PARK.

THE CANYON WAS LARGELY A LOCAL PHENOMENON BEFOR THE CIVIL WAR AND IT WAS A ONE-ARMED VETERAN OF THAT WAR WHO BROUGHT TO THIS MOST SPECIAL OF ALL CANYONS THE NATIONAL PROMINENCE THAT RESULTED IN ITS PROTECTION.

AND HERE'S WHAT JOHN WESLEY POWELL HAD TO SAY UPON ENTERING THE GRAND CANYON ITSELF.

"AUGUST 13TH, 1869.

WE ARE NOW READY TO START ON OUR WAY DOWN THE GREAT UNKNOWN.

WE ARE THREE-QUARTERS OF A MILE IN THE DEPTHS OF THE EARTH AND THE GREAT RIVER SHRINKS INTO INSIGNIFICANCE AS IT DASHES ITS ANGRY WAVES AGAINST THE WALLS AND CLIFFS THAT RISE TO THE WORLD ABOVE.

WE HAVE AN UNKNOWN DISTANCE YET TO RUN, AN UNKNOWN RIVER TO EXPLORE."

THE COLORADO RIVER, NEARLY A MILE BELOW THE RIM OF THE CANYON, IS BARELY VISIBLE TO THE MILLIONS OF VISITORS WHO PEER OVER ITS SOUTH RIM.

THE DESERT VEGETATION THAT LINES THE RIVER MOST CLOSELY RESEMBLES THAT OF THE SONORAN DESERT.

THE SONORAN DESERT, NAMED FOR THE BORDERING STATE IN MEXICO, IS THE ONE WITH THE MOST RAINFALL.

AND, IT'S THE ONE THAT LOOKS THE LEAST LIKE A STEREOTYPICAL DESERT.

THE RAIN, WHICH FALLS IN WINTER AND SUMMER, COUPLED WITH ITS MODERATE WINTER TEMPERATURES, IS WELCOMING TO MANY PLANTS OF A TROPICAL ORIGIN.

THE CLIMATE ALSO WELCOMES THE VISITORS TO ITS NUMEROUS NATIONAL MONUMENTS.

I'M RECEIVING DIRECTIONS HOW TO GET BACK TO INTERSTATE...

THE MOST RECENT IS THE SIGNATURE SONORAN DESERT NATIONAL MONUMENT ESTABLISHED IN 2001 BY PRESIDENTIAL PROCLAMATION.

WHILE THERE ARE FEW FACILITIES AND NO MARQUEE ATTRACTION, THE LAND ITSELF IS IN UNUSUALLY PRISTINE CONDITION.

A GOOD DEAL OF THE NEARLY HALF A MILLION ACRES HAS NOT BEEN GRAZED FOR OVER 50 YEARS.

BESIDES CACTI, SOME OF THE MOST CHARACTERISTIC PLANTS OF THE SONORAN DESERT ARE ITS LEGUME TREES, PALO VERDE, MESQUITE AND THE LONGEST LIVING, THE IRONWOOD, WHICH IS WORTHY OF ITS OWN NATIONAL MONUMENT.

CREATED IN YEAR 2000, THE 129,000 ACRE IRONWOOD FOREST NATIONAL MONUMENT HAS THE MOST MAJESTIC COLLECTION OF DESERT IRONWOODS ANYPLACE IN THE WORLD.

WITH THE AUTHORITY GRANTED HIM BY THE ANTIQUITIES ACT OF 1906, PRESIDENT TEDDY ROOSEVELT CREATED MONTEZUMA CASTLE NATIONAL MONUMENT.

IT'S SYNONYMOUS WITH THE GROUP THAT THE MONUMENTS WERE ESTABLISHED FOR.

ACTUALLY THEIR ANCESTORS INCLUDE THE HOHOKAMS IN THE PHOENIX VALLEY AND ALSO THE SINAGUAS IN THE FLAGSTAFF AREA.

BUT WITH THAT BLENDING OF THE HOHOKAM AND THE NORTHERN SINAGUA, THE SINAGUAN IN THE VERDE VALLEY BECAME THE GROUP THAT WERE HERE FROM 1125 TO 1425.

THERE IS DISCUSSION ABOUT IF THE POPULATION WAS 20,000 OR 40,000 AND THAT'S REALLY NOT BEEN VERIFIED.

THE SINAGUAS BUILT THIS 17-ROOM DWELLING IN A LIMESTONE CLIFF OVERLOOKING NEARBY BEAVER CREEK.

THE CLIFF DWELLINGS AT TONTO NATIONAL MONUMENT ARE NEWER, BUILT 700 YEARS AGO AND WERE INHABITED BY THE SALADO PEOPLE.

TAKING ADVANTAGE OF THE NEARBY SALT RIVER FLOODPLAIN THE SALADO PEOPLE WERE FARMERS WHO SUPPLEMENTED THEIR CULTIVATED CORN, BEANS AND SQUASH WITH A HARVEST OF SONORAN DESERT PLANTS.

THEIR DWELLINGS WERE ABANDONED AFTER ONLY 150 YEARS BUT ARE ESPECIALLY WELL PRESERVED IN THIS ARID CLIMATE.

AT ABOUT THE SAME TIME, AROUND 1450, THE HOHOKAM ABANDONED THE DWELLINGS THAT NOW COMPRISE CASA GRANDE RUINS NATIONAL MONUMENT.

THEY HAD LIVED AND FARMED IN THE AREA ALONG THE GILA RIVER FOR A THOUSAND YEARS.

THE HOHOKAM USED THE WATER FROM THE GILA RIVER PRIMARILY FOR AGRICULTURAL PURPOSES.

WE THINK THAT THERE WERE VERY LARGE FIELDS JUST DOWN SLOPE FROM THE CANALS.

WE ALSO KNOW THAT THEY HAD RESERVOIRS IN THE SETTLEMENTS FOR DOMESTIC USE AND JUST USE FOR EVERY DAY CONSUMPTION.

I WOULD SAY THAT THE CANAL TECHNOLOGY AS WE KNOW IT NOW IN THE SONORAN DESERT BOTH WITH THE HOHOKAM AND WE NOW KNOW THAT CANALS WERE BUILT AS EARLY AS 1200 B.C.

IN THE SONORAN DESERT, THAT THIS CANAL TECHNOLOGY FAR SURPASSES ANYTHING IN SOUTH OR NORTH AMERICA IN TERMS OF THE EXTENT AND THE COMPLEXITY OF IT.

SO THE SONORAN DESERT REALLY SEEMS TO HAVE BEEN ALMOST A HEARTLAND OF THE DEVELOPMENT OF CANAL TECHNOLOGY WE WOULD SAY.

THE BIG HOUSE IS ONE OF THE LARGEST, PRE-HISTORIC STRUCTURES EVER BUILT IN NORTH AMERICA.

WHILE NO STRUCTURES REMAIN TO MARK THEIR PRESENCE, THE CHIRICAHUA APACHES LIVED FOR CENTURIES IN THE WONDERLAND OF ROCKS THAT IS NOW CHIRICAHUA NATIONAL MONUMENT.

THESE WHIMSICAL SPIRES, THROUGH EROSION, WERE CARVED 27 MILLION YEARS AGO OUT OF LAYERS OF ASH DEPOSITED BY THE TURKEY CREEK VOLCANO.

THE CHIRICAHUA MOUNTAINS COMPRISE ONE OF MANY SKY ISLANDS THROUGHOUT THE DESERT SOUTHWEST.

ISLANDS OF GREEN POPULATED WITH PLANTS AND ANIMALS NOT FOUND IN THE DESERT SEA BELOW.

THE OCEAN OF DESERT THAT IS ORGAN PIPE NATIONAL MONUMENT IS BRIMMING WITH ITS NAMESAKE CACTUS.

THE ORGAN PIPE CACTUS IS MORE COMMONLY A RESIDENT OF THE MOISTER AND WARMER TROPICS TO THE SOUTH.

YOU FIND MORE FURTHER SOUTH IN MEXICO SIMPLY BECAUSE THAT IS IN THE HEART OF THE SPECIES RANGE WHERE THE CONDITIONS ARE IDEAL.

WE REALLY GET FROST AND THAT'S WHY THERE IS ORGAN PIPE CACTUS HERE.

MOST OF THE PLANTS THAT YOU SEE DO NOT TOLERATE ANY FROST.

WE GET FROST TWO OR THREE TIMES A YEAR AND IT NEVER LASTS MORE THAN A COUPLE OF HOURS.

THE MORE ARMS AND LARGER THEY ARE THE BETTER THE PLANT IS DOING.

THEY GET TO BE FAIRLY LARGE.

WE HAVE INDIVIDUALS THAT MAY HAVE 40 TO 50 ARMS.

THAT WOULD BE A VERY LARGE ONE BUT THEY CAN HAVE THAT MANY AND GET TO BE 15 FEET TALL, 18 FEET.

THIS IS ONE OF THE ONLY PLACES THE ORGAN PIPE TRAVELS ACROSS THE BORDER INTO THE UNITED STATES.

HERE IT JOINS 27 OTHER SPECIES OF CACTUS.

THEY CALL THIS ECOLOGICAL PARADISE HOME.

THIS RICH DIVERSITY IS A KEY REASON FOR ESTABLISHING ORGAN PIPE CACTUS NATIONAL MONUMENT.

THE MOST PROMINENT COMPANION CACTUS AND THE ICON OF THE SONORAN DESERT IS THE SAGUARO.

THIS STATELY CACTUS IS AN HONORED PART OF THE LIVES AND TRADITIONS OF THE NATIVE TOHONO O'ODHAM LIVING IN THE SONORAN DESERT.

WE MAKE SYRUP AND JAM AND WE DO MAKE A WINE FROM IT BUT IT'S THE CEREMONIAL THAT WE USE TO ASK FOR RAIN TO COME.

I USED TO COME WITH MY MOM, MY GRANDMOTHER, MY FATHER AND MY GRANDFATHER.

MY GRANDMOTHER, SHE WAS ALWAYS TELLING US ABOUT THE CYCLE, ABOUT THE PLANT, SORT OF WHAT I'M DOING NOW TO MY GRANDCHILDREN.

IT'S MY KNOWLEDGE OF THE DESERT AND I'M PASSING IT ON TO ALL OF MY GRANDCHILDREN AND HOPEFULLY THEY PASS IT ON TO THEIR GRANDCHILDREN.

THE SAGUARO CACTUS, ALONG WITH OTHER DESERT PLANTS AND ANIMALS, LIVE WHERE THE CLIMATE AND HABITAT ARE BEST, WHETHER WITHIN A PARK'S BOUNDARIES OR NOT.

SO WHILE IMPORTANT RESEARCH CAN HAPPEN INSIDE A PARK, THE RESULTS CAN HAVE PROFOUND IMPLICATIONS THROUGHOUT THE ENTIRE RANGE OF THE SPECIES.

ABOUT FIVE YEARS AGO WE HAD, THERE WERE MORE ACTIVE RESEARCH PROJECTS BEING CONDUCTED ON THE DESERT TORTOISE AT SAGUARO NATIONAL PARK THAN ANYWHERE ELSE IN THE RANGE OF THE DESERT TORTOISE INCLUDING THE FEDERALLY LISTED POPULATIONS.

MUCH OF WHAT WE KNOW ABOUT THE SONORAN DESERT TORTOISE WE'VE LEARNED AT SAGUARO NATIONAL PARK.

THIS PROVIDES ACTUALLY A VERY GOOD PLACE TO DO APPROPRIATE RESEARCH BECAUSE IT HAS BEEN PROTECTED FOR SO MANY YEARS.

RESEARCH IS A CURRENT PRIORITY TO THE PARK AND WAS ACTUALLY ONE OF THE PRIMARY REASONS FOR THE ESTABLISHMENT OF SAGUARO NATIONAL PARK.

IN 1933, AFTER RESEARCHERS BECAME ALARMED AT THE SEEMING DECLINE OF SAGUARO POPULATIONS, SAGUARO WAS THE FIRST NATIONAL PARK TO BE ESTABLISHED FOR THE SOLE PURPOSE OF PROTECTING A PLANT.

RESEARCH ON THE CACTUS STILL CONTINUES TODAY.

WE'RE STUDYING THE POPULATION ECOLOGY OF THE SAGUAROS IN THIS AREA.

IN 1942 80% OF THE SAGUAROS WERE TALLER THAN 12 FEET AND TODAY 85% OF THE SAGUAROS ARE SHORTER THAN 12 FEET SO THAT THERE HAS BEEN A TREMENDOUS SORT OF CHANGE IN THE HEIGHT STRUCTURE OF THE POPULATION.

IF YOU THINK OF IT IN TERMS OF CENTURIES, THE 19TH CENTURY WAS A GREAT CENTURY FOR SAGUAROS, PARTICULARLY THE LAST HALF OF THE 19TH CENTURY AND THE 20TH CENTURY WAS NOT A PARTICULARLY GOOD CENTURY FOR SAGUAROS.

THERE'S BEEN A TENDENCY TO PANIC ABOUT SAGUARO POPULATION OVER THE 65 YEAR, 67 YEAR COURSE OF THIS STUDY AND PEOPLE SAY, "OH, THEY'RE ALL DYING.

OH, THEY'RE NOT GERMINATING," AND THOSE WERE ALL TRUE.

BUT GIVEN THAT A SAGUARO WILL FLOWER FROM OVER A 70 OR 80 YEAR PERIOD SO THAT'S A LONG TIME FOR THERE TO BE A GOOD DECADE OR TWO.

SO IT'S REALLY HARD TO SAY.

THAT'S ONE OF THE THINGS THAT WE'RE DOING IS A LONG TERM STUDY AND WITH SAGUAROS UNFORTUNATELY IT HAS TO BE A REALLY LONG TERM.

THE SAGUARO SIMPLIFIES LIFE FOR RESEARCHERS BY STANDING PERFECTLY STILL.

ON THE OTHER HAND, LEOPARD FROGS, ONE OF MANY ONGOING RESEARCH SUBJECTS IN THE PARK, ARE TRAVELERS.

SCIENTISTS MUST USE THE DESERT CLIMATE TO THEIR ADVANTAGE TO FIND AND STUDY THEM.

THIS TIME OF YEAR WE'RE SEEING MAINLY FROGLETS THAT HAVE JUST METAMORPHED FROM TADPOLES AND THEY CAN RANGE IN SIZE FROM ABOUT MAYBE A NICKEL TO ABOUT A QUARTER AND WE KIND OF ASSUME THAT IT JUST DEPENDS ON THE AMOUNT OF PREY THAT THEY'RE ABLE TO GET.

IT'S RIGHT BEFORE THE RAINS AND WE KNOW THAT AS THE END OF SPRING STARTS TO HEAT UP AT THE BEGINNING OF SUMMER THAT THE WATER IS GOING TO BE LIMITED TO CERTAIN POOLS.

THAT'S WHY WE'RE OUT HERE WHEN IT'S HOT BECAUSE THAT'S WHEN THE LEAST AMOUNT OF WATER IS GENERALLY AVAILABLE.

RESEARCH AND MANAGEMENT AT SAGUARO NATIONAL PARK IS COMPLICATED BY LOCATION.

ITS TWO UNITS FALL ON EITHER SIDE OF THE CITY OF TUCSON.

THE PARK WAS ORIGINALLY ESTABLISHED MILES FROM THE CITY.

NOW ITS NUMEROUS NEIGHBORS ARE OFTEN UNCOMFORTABLY CLOSE, A GROWING PROBLEM FOR MANY SOUTHWESTERN PARKS.

SO PARKS THAT ADJOIN SORT OF RELATIVELY MAJOR URBAN AREAS HAVE UNIQUE SETS OF CHALLENGES, ESPECIALLY DESERT PARKS BECAUSE AS THE BOUNDARIES OF THOSE PARKS GET ENCROACHED UPON AND DEVELOPED, WHAT HAPPENS IS THE BIOLOGICAL FUNCTION OF THAT PLACE DECREASES APPRECIABLY.

SO THESE PARKS THAT WERE REALLY ONCE PART OF THIS VAST INTERCONNECTED LANDSCAPE OF WILD PLACES NOW BECOME THESE ISOLATED LOCATIONS AND THEY DECREASE SOMEWHAT IN THEIR BIOLOGICAL FUNCTIONALITY.

SO WHAT HAPPENS IS AS MORE OF THE LANDSCAPE GETS CONVERTED TO ANTHROPOGENIC HUMAN USES IS THAT PARKS BECOME MORE AND MORE VALUABLE TO THAT SORT OF CONSERVATION OF BIOLOGICAL DIVERSITY PERSPECTIVE.

YOU CAN THINK OF SAGUARO NATIONAL PARK FOR EXAMPLE AS ONE THAT WAS ESTABLISHED IN A RELATIVELY WILD AND PRISTINE PLACE BUT NOW TUCSON AND THE SURROUNDING TOWNS ARE SORT OF GROWING AROUND IT, SORT OF ISOLATING IT.

SO EVEN THOUGH THAT PROVIDES SOME CHALLENGES TO MANAGING A PLACE LIKE THAT, I THINK THAT THE ROLE OF THAT PLACE IN TERMS OF SOME OF THE PARK'S MANDATES AND THAT'S CONSERVATION OF PLANTS AND ANIMALS IN THOSE PLACES, BECOMES REALLY IMPORTANT.

TO CONFRONT THESE CHALLENGES THE PARK SERVICE IS COUNTING ON AN ARMY OF ITS MOST ENTHUSIASTIC BOOSTERS, ITS VISITORS.

THE PRIMARY MISSION FOR SAGUARO IS THE SAME REALLY AS ANY NATIONAL PARK SERVICE UNIT AND THAT IS AGAIN TO PROTECT AND PRESERVE THE NATURAL AND CULTURAL RESOURCES AND THE CULTURAL HERITAGE HERE.

AND THEN ALSO TO PROVIDE AT THE SAME TIME FOR THE ENJOYMENT AND THE UNDERSTANDING OF THE VISITORS WHO COME HERE SO IT'S KIND OF A DUAL MISSION THAT CAN BE CHALLENGING AT TIMES.

BUT IT'S ONE THAT IS VERY WORTHY AND ONE THAT WE FEEL THAT IS CRITICAL ESPECIALLY RIGHT NOW ENSURING THE NEW GENERATIONS THAT THESE PARKS ARE RELEVANT.

THESE MOST CHERISHED OF PUBLIC LANDS, SOON TO BE IN THE HANDS OF FUTURE GENERATIONS, SUGGEST A DEFINING IDEAL FOR US AS A COUNTRY.

AS NOVELIST AND WILDERNESS ADVOCATE WALLACE STEGNER SAID, "NATIONAL PARKS ARE THE BEST IDEA WE EVER HAD.

ABSOLUTELY AMERICAN.

ABSOLUTELY DEMOCRATIC.

THEY REFLECT US AT OUR BEST."

I THINK YOU'D BE REALLY HARD PRESSED TO FIND ANYONE TO SAY THAT THE IDEA OF ESTABLISHING ANY OF OUR NATIONAL PARKS WAS A BAD IDEA, IN FACT EVEN SOMETHING SHORT OF BRILLIANT.

ONE OF THE POSITIVES THAT COMES WITH ESTABLISHING AREAS FOR CONSERVATION I THINK IS THAT LONG TERM PERSPECTIVE.

INEVITABLY WHEN WE CHOOSE A LAND USE FOR A PLACE WE HAVE THE OPTIONS OF REALLY MAKING THAT AN ADVANTAGE TO A FEW PEOPLE IN TERMS OF WHO CAN CAPITALIZE ON THAT VERSUS ENJOYMENT BY MANY, MANY PEOPLE AND I THINK THAT IN GENERAL CONSERVATION LANDS REQUIRES THAT LONG TERM MULTI-GENERATIONAL PERSPECTIVE IN SAYING, IF YOU WANT TO DO SOMETHING THAT'S IMPORTANT FOR THE LONG TERM, THEN SETTING ASIDE PARKS IS REALLY PRETTY MUCH A WINNER IN MY BOOK.

GENERATIONS FROM NOW PEOPLE WILL, IF WE DON'T SET ASIDE MORE, WILL ASK, WHY DIDN'T WE?

FUNDING FOR THIS PROGRAM WAS PROVIDED BY DESERT PROGRAM PARTNERS.

TO LEARN MORE ABOUT OUR NATIONAL PARKS AND HOW TO GET THE MOST OUT OF YOUR VISIT, PLEASE VISIT US ON THE WEB AT ORIGINALS.AZPM.ORG /SOUTHWESTERNGEMS.

SOUTHWESTERN GEMS: OUR DESERT NATIONAL PARKS IS AVAILABLE ON DVD.

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