The Sonora Desert, which stretches through the southwestern United States and northern Mexico, is the most diverse desert in the world. The iconic giant pillar cactus in the desert is more than 10 meters tall, and just one plant is enough to be amazing, and they are even lined up. Under the bright sun, the "copper branches and iron arms" of the giant pillar, the woodpeckers that nest in the holes in their stems, the bright inflorescences in the bushes, and the flocks of "white-collar" small wild boars... all interpret the vitality of the desert.
"White collar" small wild boar collared Pecari tajacu (Pecari tajacu) roams in groups in desert cacti-rich areas
The world's largest cactus
There are four major deserts in North America: Sonora, the Great Basin, Mojawi and Chihuahua. The Sonoran Desert covers southeastern California, southwestern Arizona, most of Mexico's Sonora, and the northern part of baja California's east coast, with a total area of about 223,000 square kilometers. Unlike the barren land of yellow sand that we remember, the Sonora Desert is home to more than 2,000 species of plants, ranking first in the global desert plant diversity rankings. More than 560 species of plants have adapted to extremely dry and hot environments, more than 160 species need shelter from other plants to complete natural renewal, and the endemic species, the world's largest cactus giant column (Carnegiea gigantea), is undoubtedly Sonora's proudest symbol.
The Plant Diversity of the Sonora Desert is particularly characteristic of the Giant Pillar Cactus.
In addition to its abundance of plants, the Sonora Desert is home to about 120 species of mammals, 350 species of birds, 100 species of reptiles, 20 species of amphibians and 30 species of fish. It is a global biodiversity hotspot and is listed by WWF as the "Global 200" Sonora-Baja Desert Ecoregion. Within the United States, about 60 percent of the Sonora Desert's habitat has been altered by agriculture, livestock, groundwater over-exploitation and urbanization, and Saguaro National Park, just outside of Tucson, arizona's major town, is one of the rare sanctuaries. It is also one of four national parks in the United States named after plants, the other three being the Sequoia, Giant Fir and Joshua Tree National Parks in California.
Sonora Desert Creatures
In the middle of winter, we head to Giant's Pillar National Park. When you leave Show Low in the morning, it is cloudy and snowy, and it is already sunny when you arrive in Tucson at noon. The average annual temperature in Tucson is as high as 21.6 °C, and the average annual precipitation is only 303 mm, which is evident in the degree of dry heat and dryness of the climate. Giant's Pillar National Park consists of the Rincon Mountain District on the eastern outskirts of Tucson and the Tucson Mountain District in the western suburbs, with a total area of 370 square kilometers and a total of about 1.6 million Giant Pillars.
The road stretches on a gentle slope at the foot of the mountain, and we are surrounded by an array of giant pillars: pointing straight to the sky, standing above the low desert vegetation, densely packed, like green waves crashing into the eyes. The Tucson Mountains have the world's largest population of giant pillars, most of which are close to 10 meters in height, a few can reach more than 15 meters, the diameter of the stem is 30 to 75 cm, and there are multiple "arms", which does look like a bit of a "giant" image. The surface of the stem has multiple raised longitudinal edges and dense spikes, which have a great effect on adapting to arid environments. In the dry season, cacti plants such as giant pillars shrink in size due to the continuous loss of water, and once it rains, they absorb water to the maximum and expand rapidly, usually the stem of a large giant column can store about 1 ton of water, without these longitudinal edges like accordion bellows "stretching", the epidermis will crack.
A short-tailed cat (also known as a North American bobcat) climbs to the top of a giant pillar more than 10 meters high to avoid being hunted by mountain lions.
Giant pillars have a lifespan of up to 200 years, they grow slowly, 40 to 75 years old before they flower and bear fruit, and grow their first "arms". Every year in April and May, white flowers bloom densely on the thorn pedestal near the top of the giant's column stem, wafting with the fragrance of ripe melon, and hundreds of pale yellow stamens are decorated with pollen, waiting for pollinators to visit. It is also arizona's state flower. When the fruit ripens, the peel cracks, revealing a red flesh embedded with tiny seeds, similar to the red-hearted dragon fruit of the cactus family.
Giant pillars grow slowly, growing to 1 meter tall in 30 years after seed germination, flowering and bearing fruit around 50 years old, and most of them take 70 years to grow the first "arm", with a lifespan of 200 years.
The flowers of the Giant Pillar bloom on the thorn seat near the top of the stem
The genus Giant Pillar contains only one species of giant pillar, cactus, and such a single genus often has a unique taxonomic status, but there is not much scientific basis for the establishment of the giant column genus. In the 1920s, when it was learned that Andrew Carnegie, the "king of steel" in the United States, was going to visit his funded Tucson Desert Laboratory, two botanists in New York named Carnegiea to build a new genus of giant columns in the hope of winning more donations for the laboratory. It is said that Carnegie was very angry when he learned the truth, but this genus name, which was born from the "pat on the back", is still used today.
Huge "networks"
Giant pillars are mainly distributed in two vegetation belts, desert and thorny bushes, and all species in them are directly or indirectly related to giant pillars, and together they weave a huge "relationship network".
Because of its slow growth, the juvenile giant pillars were short and fragile. The seeds germinate for 2 months, the stem diameter is less than 5 mm, and after 8 years, it is only 2 cm high, and wild boars, hares, etc. can inadvertently crush them to pieces. Scorching sun, drought, heat and frost are all extreme threats to the survival of seedlings, with only about 1% of Giant Pillar seedlings surviving the first year of life. Giant columns are particularly sensitive to low temperatures, and although they are resistant to short-term frost and snow, they freeze to death for a little longer duration, so they usually grow at altitudes below 1400 meters above sea level and sub-zero low temperatures lasting no more than 36 hours.
The juvenile giant pillar is short and fragile, and needs to be cared for by the "nanny plant".
Giant Pillars are sensitive to low temperatures and freeze to death on persistent frost and snowy days.
"Cool under the big tree" is its survival strategy. Desert and thorny bushes are rarely arborvitae, and The 10-meter-tall Multi-Flowered Flat-shafted Wood (Parkinsonia Florida) and the Less than 1 meter Desert Ragweed (Ambrosia dumosa) are the favorite "nanny plants" of giant pillar seedlings, with about 90% of the seedlings growing in their shadows. The benefits of the "Nanny Plant" are obvious: on the one hand, it can shield the scorching sun from the scorching sun – the temperature of the desert soil in the hot summer is as high as 60 ° C, while in the shade of the multi-flowered flat-shaft tree is only 40 ° C; on the other hand, the winter is conducive to reducing the damage of frost to the giant pillar seedlings.
There is no free lunch in the world, and the protection of the "nanny plant" also has a price. Studies have shown that due to the obscuration of desert ragweed, the effective solar radiation used for photosynthesis by Giant Pillar seedlings is reduced by 77%. In addition, it competes with the "nanny plant" for water, and in harsh living environments, giant pillar seedlings tend to compromise "wisely".
Juvenile giant pillars need shelter from other plants, and when they reach adulthood they can provide shelter for many animals. Birds such as the white-winged mourning pigeon (Zenaida asiatica), the red-tailed (Buteo jamaicensis) and the black-headed American vulture (Coragyps atratus) lay their eggs and raise their nests with branches at the base of the "arms" of the giant column.
Relying on the giant pillar's sharp spines and straight main stems, these birds do not have to worry about the sneak attacks of natural enemies such as rattlesnakes. With a little attention, you can find many holes of about 5 centimeters in diameter above the middle of the giant column, which are not scars left by lesions, but nests pecked by The Melanerpes uropygialis and the Yellow Flappers chrysoides. Of the two types of woodpeckers, the Gila woodpecker is smaller, usually pecking holes in the middle of the loose wooden ribs of the giant pillar; the yellow-winged bird is large, nearly 30 cm long, and can peck through the wooden ribs, so it often pecks at the upper part of the denser wooden ribs. The abandoned burrows of the two woodpecker species are also not vacant and are often exploited by the world's lightest owl, the Micrathene whitneyi (weighing about 40 grams).
The Gila woodpecker (Figure 1) and the yellow flappy winged whisker (Figure 2) peck holes in the stems of giant pillars as nests
The base of the giant pillar "arm" becomes the comfort nest of the bighorn owl
The world's smallest owl, the Owl, is a hardcore tenant of the Giant Pillar, and when the woodpeckers move their front feet away, they move into their "new homes" on their back feet.
The flowers of the Giant Pillar begin to bloom in the evening and wither within 24 hours. During the flowering period in April and May, the animals enjoy a nectar feast in "two shifts" to help the giant pillar complete the pollination task. The "day shift" consists mainly of bees and birds, including white-winged mourning pigeons; the main force of the "night shift" is moths and small proboscis bats (Leptonycteris yerbabuenae). By the end of June and the beginning of July, the fruit of the giant pillar was ripe, and its rich water and dry matter were an important food ration for many animals.
The small proboscis bat is an important pollinator of the Giant Column
Before the fruit falls, birds such as the white-winged mourning pigeon take the lead and feast on the stem of the giant pillar. According to the survey, giant pillar fruit accounts for 40% to 70% of the food of 13 species of birds. The Gila woodpecker is busy feeding the chicks in June, and in addition to insects, the fruit of the giant pillar is also a good ingredient for feeding the chicks. When the fruit falls to the ground, there are more animals to enjoy: insects, reptiles, rodents, even-hoofed animals, and even carnivores are tempted by the double temptation of water and heat. Even after death, the remains of the Giant Pillar can still play an important ecological role, and the decaying tissue is eaten by flies and Coleoptera insects, which in turn become the delicacies of lizards...
The white-winged mourning pigeon (top) and the house suzaku peck at the red fruit of the giant pillar
The giant pillar dies and reveals its wooden bones
In addition to animals, the Giant Pillar is also indispensable to the local indigenous people. The Tohono O'odham tribe lives in southern Arizona and northern Sonora, Mexico, with about 20,000 people, and occupies a prominent position in their lives, from spiritual beliefs to building materials, food, and giant pillars. The Tokhno Oham believed that after death, people would incarnate as pillars of giants, so they were in awe of them and would not deliberately destroy them. The long, straight wooden ribs left behind after the death of the giant pillar are rare wood in the desert and are used to build facilities such as shade sheds and fences; the boot-shaped empty shells pecked by woodpeckers are called "giant pillar boots" and used to hold water; and the fruits and seeds of the giant pillar are important food.
The "Giant Pillar Boots" pecked by woodpeckers can be used to hold water
Every year in June and July, the harvest of the giant pillar of the Tokhno Oham people begins, marking the beginning of the New Year. Due to the long time it takes, the tribes usually camped in areas where the Giant Pillar was concentrated. They used the wooden ribs of the giant pillar to shoot down the fruit and bring it back to the camp, except for raw food, most of which were boiled into syrup and jam; the seeds were dried and ground into flour to make bread; the harvest was near the end, and then some of the syrup was brewed into wine for rain. To this day, the Tokhno Oham people still retain this custom. During the harvest season, Giant's Pillar National Park allows them to camp in the park, continuing the tradition of harmonious coexistence between man and nature in the Sonora Desert for thousands of years.
Picking the fruit of the Giant Pillar is a traditional custom of the Tokhno Oham people, the indigenous people of the Sonora Desert, and continues to this day.
This article is from the March 2021 issue