50 free Joshua Tree National Park trivia questions with answers — geography quiz, new questions added Aug 2026.
This Joshua Tree National Park trivia quiz covers the Southern California park where the high Mojave Desert meets the low Colorado Desert amid piles of rounded granite boulders and forests of spiky yuccas. Questions cover the geology of the inselbergs and the Wonderland of Rocks, the two deserts and their plants, the yucca moth, the desert tortoise, the fan palm oases and the dark skies, along with the climbing scene and Keys View. The history side takes in the Pinto Culture, the Serrano, Cahuilla and Chemehuevi, the Mormon settlers who supposedly named the tree, the McHaney rustlers, the Lost Horse and Desert Queen mines, Bill Keys and his ranch, the socialite Minerva Hoyt who won Franklin Roosevelt's 1936 monument, the 1994 upgrade to national park, and pop-culture footnotes from Gram Parsons' stolen corpse to the U2 album cover tree that is nowhere near the park. Difficulty runs from easy to expert and is marked on every question, so it works for a campfire game at Hidden Valley or a serious park-nerd challenge. Every answer was checked against Wikipedia and each question carries its citation. If you enjoy it, try our Death Valley and US National Parks quizzes next.
30 of 50 questions with answers and explanations. Play the quiz
Q 01Joshua Tree National Park lies about 130 miles east of which big city?
Los Angeles
It straddles Riverside and San Bernardino counties, with Palm Springs, Palm Desert and Indio among the nearest towns.
Q 02The park straddles which two deserts?
Mojave and Colorado
Elevation is the dividing line: the higher, cooler desert grows the namesake trees while the lower one below 3,000 feet is creosote, ocotillo and cholla country.
Q 03The Joshua tree is actually what kind of plant?
A yucca
It is a monocot with no annual rings, so its age is hard to judge; the tallest reach about 49 feet.
Q 04Which group is commonly credited with naming the Joshua tree after a biblical figure?
Mormon settlers
The story says the shape recalled Joshua raising his hands toward Canaan, though no contemporary record of the naming survives and the tale fits Moses better.
Q 05Which insect pollinates the Joshua tree, laying its eggs in the flowers as it does so?
Yucca moth
The larvae eat some seeds but leave enough to grow, and the tree can abort ovaries that carry too many eggs.
Q 06Who first formally described the Joshua tree for science in 1871, during the Wheeler Survey?
George Engelmann
The Cahuilla call the tree hunuvat chiy'a; the Spanish name izote de desierto means desert dagger.
Q 07Which president proclaimed Joshua Tree National Monument in August 1936?
Franklin D. Roosevelt
He used the 1906 Antiquities Act to protect about 825,000 acres; in 1950 some 290,000 acres were cut out to allow more mining.
Q 08Which Pasadena socialite and desert-plant campaigner is credited with winning protection for Joshua Tree?
Minerva Hoyt
She shipped seven freight cars of rocks, plants and sand to a New York garden show in 1928; a park peak and an asteroid now carry her name.
Q 09Which 1994 law turned the monument into Joshua Tree National Park?
California Desert Protection Act
It also added 234,000 acres to the park.
Q 10At about 795,000 acres, the park is slightly larger than which US state?
Rhode Island
Roughly 430,000 of those acres are designated wilderness, where bikes are banned but permitted horses may go.
Q 11The park's famous piles of rounded boulders are made of what rock?
Monzogranite
Groundwater seeping along rectangular joints rounded the blocks underground, then flash floods stripped the soil to leave the piles, called inselbergs.
Q 12How old are the park's oldest rocks, such as the Pinto Gneiss?
1.7 billion years
They surface in the Cottonwood, Pinto and Eagle mountains, far older than the granite that later pushed up among them.
Q 13Which famous fault runs just southwest of the park, with related faults like the Blue Cut crossing inside it?
San Andreas
The compression along it lifted the park's Transverse Ranges, and it can be seen from the park's southern lookout.
Q 21Between 1894 and 1931 the park's most successful mine produced roughly how much gold?
10,000 ounces
It also yielded 16,000 ounces of silver, and the hunt for fuel to run steam pumps stripped the surrounding hills of trees.
Q 22Who was the rancher-miner whose Desert Queen Ranch is the best-preserved early homestead in the park?
Bill Keys
He arrived in 1910, took over rustler Jim McHaney's property, improved Barker Dam and hauled in the Wall Street Mill to crush ore.
Q 23The rancher who built the Desert Queen Ranch was sent to San Quentin for what?
Shooting a neighbour in a dispute over a mill
Q 14Which lookout in the park's south takes in the Coachella Valley, the Salton Sea and Palm Springs?
Keys View
It also looks straight along a great fault line to the Santa Rosa Mountains.
Q 15Washingtonia filifera, found in five oases in the park, holds what distinction?
Only palm native to California
Water flows year-round at these rare spots and wildlife crowds in; the town of Twentynine Palms is named for palms planted around one such oasis.
Q 16Which spring at Twentynine Palms was a village site for the Cahuilla and Chemehuevi peoples?
Oasis of Mara
The Chemehuevi called it Mar-rah, and the palms planted around it gave the town its name.
Q 17The park's earliest known residents, whose spear points were found in a basin in the 1930s, are called what?
Pinto Culture
They hunted and gathered there between about 8000 and 4000 BCE; the basin and a mountain range in the park carry the same name.
Q 18Which Spanish officer led the party that made the first European sighting of Joshua trees in 1772?
Pedro Fages
They were chasing Native converts who had fled a mission in San Diego; Jedediah Smith's trappers passed nearby in 1826.
Q 19The McHaney brothers, who moved in near Twentynine Palms in 1888, ran what kind of gang?
Cattle rustlers
They hid stolen stock in a box canyon at Cow Camp; Jim McHaney later muscled in on the Desert Queen Mine.
Q 20What was the most successful of the roughly 300 mines worked in the park area?
Lost Horse Mine
It produced gold and silver worth about $5 million in today's money; Johnny Lang bought the claim after losing his horses in the valley that now bears the name.
He killed Worth Bagley in a quarrel over the Wall Street Mill, was paroled in 1950 and pardoned in 1956.
Q 24Which famous author helped win the jailed Desert Queen rancher a pardon in 1956?
Erle Stanley Gardner
Keys had educated himself in the prison library; his ranch buildings date from 1910 to his death in 1969.
Q 25Which miner-cattleman built the original dam at a rainwater tank in 1900 and gave it his name?
C.O. Barker
Ranchers dug wells and built such tanks across the region; grazing continued in the park until 1945 and the dam joined the National Register in 1975.
Q 26Why did the park close at least 17 sites, including a historic dam and Rattlesnake Canyon, to the public?
Graffiti and vandalism
Officials blamed a surge in vandalism on social media; a graffiti artist known as André was convicted in 2015 after posting photos of his boulder painting.
Q 27Joshua Tree originally became popular with rock climbers for what reason?
Winter practice while Yosemite was snowbound
The quartz monzonite is rough because no ice ever polished it, and thousands of short routes are a short walk from the road.
Q 28The park's climbing rocks are rarely taller than about how many feet?
230
Some routes such as the Schwarzenegger Wall and Zombie Woof Rock are permanently closed; others shut seasonally for wildlife.
Q 29In which year did the International Dark-Sky Association designate Joshua Tree a Dark Sky Park?
2017
It is a favourite stargazing spot for Southern Californians, far from the glow of the coastal cities.
Q 30Which threatened reptile of the park's creosote flats gets most of its water from the plants it eats?
Desert tortoise
Its numbers have fallen with habitat loss and climate change; the chuckwalla shares its taste for creosote.