Introduction: The big tree azalea is known as the king of azaleas in the world, growing in parts of the Gaoligong Mountains in southwest China, and the mountains are high and the road is far away, which is rare to see. At the beginning of the new spring of 2023, the honey plant habitat began to conduct scientific research on the habitat of the large tree rhododendron in Gaoligong Mountain. With the enthusiastic help of leaders at all levels in Nujiang Prefecture, the expedition team investigated the habitat and growth of the rhododendron, and took a large number of precious photos, making this scientific expedition a complete success.
Gongshan County big tree azalea
Big tree cuckoo near Gongdu Highway
The azaleas in the Gaoligong Mountain section of Gongshan County, Nujiang Prefecture, northwest Yunnan have a wide variety of rhododendron species, and are a sacred place for studying azaleas. As early as the early twentieth century, the rich rhododendron resources of Gongshan County attracted Forrest, Kington Ward and others, and led expeditions to investigate this place many times. In March 1917, Forrest embarked on his fourth expedition to southwest China. Through years of investigation, research and collection, Forrest found that the distribution of rhododendrons in southwest China seems to have a unique pattern, that is, species are concentrated in the northwest and gradually sparse in the southeast.
The northern section of Gaoligong Mountain is forested and snow-capped peaks
To this end, Forrest set his sights on the Chayu area in Tibet, believing that this is the origin of the world's azaleas, and Forrest tried every means to apply for entry into the Chayu area to investigate, but was rejected and warned by local officials on the grounds that there was a rebellion in the area and his safety could not be guaranteed. Because according to the regulations, he had to obtain the consent of the local government to go, Forrest had no choice but to send his own expedition to the Chasumi area to investigate. In the second half of 1917, Forrest sent Gan Dong to lead an expedition to the Chayu area for the first time. Because Gandong is Tibetan, there are not many restrictions on movement in this area, but the number of specimens harvested is limited.
Nu River and Gongshan County
In May 1918, Forrest sent Zhao Chengzhang and two other experienced collectors to Tsizhong . They will work with Gandon to explore Chayu during the war. They entered the area twice, each lasting more than a month, to the northwest of Kawakarpo (Meri Snow Mountain) and elsewhere. And in May, an expedition led by Zhao Chengzhang and Gan Dong collected specimens of the cuckoo pattern in Gongshan County.
the cuckoo
Cuckoo type specimen
Collector/Expedition: George Forrest
Date of collection: May 1918
Royal Botanic Gardens, Edinburgh
In the first half of 1919, Gandong again explored the Chayu area in Tibet, but the number of specimens brought back by Gandong after the expedition was the same as the previous one, which was very unsatisfactory and not as rich as Forrest imagined, which made him doubtful and disappointed in the Chayu area.
In August 1919, Gan Dong led an expedition to explore the Dulongjiang-Nujiang watershed, but the gains were limited, and Forrest was very dissatisfied, so in July 1921, Forrest and Zhao Chengzhang led an expedition of 7-8 people from Xuehao Village to explore the area again. They collected 45 species of rhododendrons and about 100 species of plants of other genera here, and Forrest harvested a lot of rich rhododendron resources, which made Forrest attach great importance to the Gaoligong Mountain in the Dulongjiang-Nujiang watershed. According to the records of the "List of Wild Plant Species of Gaoligong Mountain in Nujiang Prefecture" published in 2022, Gaoligong Mountain in Nujiang Prefecture has a total of 216 species of rhododendrons, of which 135 species are Rhododendron species, which is the true kingdom of rhododendrons.
Dulongjiang-Nujiang watershed
Large tree rhododendron specimen
Collector/Expedition: George Forrest
Date of collection: September 1919
Natural History Museum, London
Rhododendron large tree type specimen
Collector/Expedition: George Forrest
Date of collection: March 1921
Royal Botanic Gardens, Edinburgh
In 1919, Gan Dong came to the Dulongjiang-Nu River watershed to collect plant specimens, and in September collected a specimen of the large tree rhododendron , the specimen is now in the London Museum of Natural History, which is the earliest specimen of the big tree rhododendron that can be seen, that is to say, the big tree rhododendron was first found in Gongshan County. Because the specimen has only three leaves, it cannot be used as a type specimen, so it has not attracted much attention. The type specimen of Rhododendron was collected in March 1921 from the Gaoligong Mountain section of Tengchong. The big tree azalea is the tallest rhododendron growing in the world, and is known as the king of azaleas in the world, and its status is extremely respected. The large tree rhododendron in the Tengchong area is rare because it grows in the core area of Gaoligong Mountain National Nature Reserve, and it takes various complicated procedures to enter, and then it takes 7 hours to return accompanied by a forest ranger. In the Gaoligongshan area of Gongshan County, there are four distribution areas of the big tree rhododendron, Longyuan in the northwest, three pairs in the southwest, Dulong in the middle, and Ji in the southeast. Of course, they are all located in the core area of Gaoligong Mountain National Nature Reserve, and strict applications are required to enter these areas.
Big tree cuckoo
At the beginning of the new year of 2023, the honey plant habitat group came to Gaoligong Mountain and began a scientific expedition to find the habitat of the large tree rhododendron. This scientific expedition received strong support from the Nujiang Prefecture Propaganda Department, the Forestry and Grassland Bureau, and the Gongshan County Forestry and Grassland Bureau. The staff of the Nujiang Forestry and Grassland Bureau carefully checked the declaration materials we provided, and in order to complete the procedures as soon as possible, the staff did not take a break at noon, and worked overtime to handle the procedures for us to enter the mountain, so that our scientific expedition could be carried out smoothly, and I really appreciated their rigorous and enthusiastic work style.
Gaoligong Mountain
On the night of March 3, we drove from Nujiang Prefecture to Gongshan County, and in the early morning of the 4th, we came to the Gongshan County Forestry and Grassland Bureau in exchange for a certificate to enter the mountain. Because it was Sunday, the staff gave up rest, came to the Forestry and Grassland Bureau to give us a certificate, detailed introduction to the mountain, and at the same time contacted the ranger to accompany us at that time, and repeatedly instructed, because last year the snow on the mountain here was very heavy, the spring snow melted, causing many road sections of landslides, mudslides, rockfalls, we must pay attention to safety, let us be very grateful.
Gaoligong Mountain
Leaving the Forestry and Grassland Bureau, at 9 o'clock, we rented a car and went to Dulongjiang, and the car left Gongshan County and entered Gaoligong Mountain along the Gongdu Highway in the northwest. After its completion in 1999, the Gongdu Highway was known as the most dangerous Devil's Highway in Yunnan, and although the scenery along the road is picturesque and beautiful, it is surrounded by abysses on both sides of the road, which is dangerous and challenging to drive, and heaven and hell coexist here. The east side of Gaoligong Mountain has become rosé and willow green, plum blossoms are blooming, and spring is full of joy. In the distance, Peili Village is built halfway up the mountain, and the brand-new houses present a thriving new atmosphere against the background of various flowers such as peach and plum.
View of Perry Village
Just across the road from Perry village, we met a team riding up the mountain, and I was very emotional, young is good, such a steep road, they can go to conquer, but I also have doubts about their ability. The car gradually drove to the high altitude, and the scenery on the roadside obviously began to change, from cash crops such as peach and plum under the mountain to evergreen broad-leaved forest, and then from broad-leaved forest gradually to mossy hemlock, pine trees, etc. Because the slope of Gaoligong Mountain is extremely steep, limited by the terrain, the road surface is relatively narrow, and there are some places where it is impossible to return the car, just like the nine-curved ileum wrapped around the mountain. The snowmelt on the mountain merges into a stream, cascading down the steep cliff face, forming a torrential waterfall, which also causes landslides and rockfalls, and many of the concrete guardrails on the outside of the road are scarred by stones, so this road is still quite dangerous to walk on rainy days.
Roadside waterfall
Soon, the car came to the vicinity of the snow line of the Gongdu Highway, surrounded by ancient and dense cedar trees, and the large snow appeared on both sides of the road very unreal. Because in the past, the road had to pass through the Heipu Poluo Pass at an altitude of 3380m, and the snow here was deep in winter, and traffic was closed for 6-7 months every year, making Dulongjiang Township west of Gaoligong Mountain isolated from the world in winter and becoming an isolated island. In 2014, the government rebuilt the Gongdu Highway and built a 6680m tunnel under the Heipu Poloya Pass, which was reduced to 3022m to 2842m above sea level, so that Dulongjiang Township can also be opened to traffic in winter. However, the snow line of the Gongdu Highway is about 2700m, so there is still some snow on the tunnel entrance lead, and two snow-proof shelters are set up in the most dangerous section of the tunnel to prevent snow on the mountain from blocking the road. The car came to the snow shelter cave, the roof of the shed was full of snow, the side openings of the shed were also covered with snow, and the melting snow water from the mountain rushed down from the snow on the roof of the shed, which made people feel shocked.
Gaoligong Mountain
Beyond the snowproof cave, a flat snow slope appears in front of it, presumably formed by the muck piled up in the tunnel, and there are many vehicles parked on the side of the road, and many tourists are excited to play in the snow here. Passing through the tunnel, we come to a flat ground where the guarding station where the ranger agreed to meet is located. The steep slopes and harsh environment, surrounded by snow and tall hemlock trees, show the arduous work of forest protection. After some communication, the ranger got into our car, and we explained to him that we were here mainly to look for large tree rhododendrons.
Perhaps it was a difference in language communication, but the ranger only understood that we were here to look for azaleas, so he said that there was not far away, which made us overjoyed. The car drove a short distance forward, and the ranger pointed out the window and said isn't that the cuckoo you are looking for? We followed the direction of his finger and saw a purple-red azalea blooming in the snow on a cliff by the side of the road. Everyone quickly got out of the car to take a closer look, this rhododendron is five or six meters tall, and it is covered with purple flowers, but the leaves and flowers of this azalea are obviously small, which is far from the characteristics of domineering side leakage such as the large tree azalea and large leaves and flowers we are looking for. Asked the ranger again, the ranger said that he only knew azaleas, and the specific species was unknown. Helplessly, we had to say goodbye to the rangers, and we decided to look for the big tree cuckoo on the Gongdu Highway by ourselves.
Gaoligong Mountain
Just wanted to get on the car, suddenly saw several clusters of strange flowers blooming on the side of the thick snow on the side of the road, each cluster of flowers is like a round pearl inlay, white outside, pink purple inside, under the background of snow, like a girl's rosy cheeks, full of youthful vitality, people feel the tenacity of natural life. Later inquiries revealed that this is Petasites tricholobus Franch., a species of butterbur in the Asteraceae family. This flower is a traditional Chinese medicine, and the most amazing thing is that it can treat poisonous snakebites.
Tricula
Back to the car, the car drove on the road, tall azalea trees full of flowers kept flashing on the side of the road, get out of the car and look closely, all the same as the first tree, not a large tree azalea. Because this azalea has small leaves, purple-red flowers, and the trunk is bursting like a crape myrtle, it is brownish-red, strong and upright, and very beautiful. Later, I asked Dr. Ma Yongpeng, a rhododendron expert at the Kunming Institute of Botany, Chinese Academy of Sciences, because the photos we took only focused on the flowers of the azalea, ignoring other features of photographing azaleas, especially the hairy quilt behind the leaves of the azalea species, so Dr. Ma could only tell us that this azalea may be a rhododendron.
The car stopped and walked on the road, and although there were clusters of purple red everywhere on the nearby hillsides and distant hillsides, most of them were light pillar cuckoos, not the big tree cuckoos we were looking for. Without an exact target location, looking for a big tree cuckoo in the huge Gaoligong Mountain is undoubtedly looking for a needle in a haystack, and it is inevitable that the heart will become anxious. After all, according to tradition, large trees and rhododendrons grow in the protected area on the beaten track, and it is rare to see them, and there is no bottom in our hearts like ours along the road to find if we can see them.
Light pillar cuckoo
Light pillar cuckoo
The car left the tunnel entrance for about a kilometer, and the altitude gradually decreased, and at about 2700 meters above sea level, the light column cuckoo on the side of the road disappeared. Just when I was a little disappointed, suddenly a rhododendron tree with a large purple-red flower crown appeared at the bend on the side of the road, standing proudly on a steep cliff less than ten meters or so on the outside of the road, and I quickly asked the driver to stop the car and come to the side of the road to take a closer look. I saw her full of huge clusters of purple and red flowers; The veins are clear, some like the big leaves of loquats, which is exactly the big tree cuckoo that we are looking for in this scientific expedition, and suddenly makes us feel that happiness came too suddenly, and it can be said that it takes no effort to come at all. Although there are 9 Rhododendron trees in Gaoligong Mountain, the only place where Rhododendron trees can be observed on the road is Gongdu Highway, which is also the only place in China where Rhododendron trees can be freely observed.
Big tree cuckoo
Big tree cuckoo
The big tree azalea is known as the king of azaleas in the world, is the treasure of Gaoligong Mountain, the star plant, and the earliest rhododendron in the wild. The big tree azalea generally begins to bloom in the wind and snow around the Spring Festival, not with the flock, domineering and arrogant, not dusty. It blooms from February to March and can bloom for about 60 days, making it one of the longest blooming azaleas in the wild. The big rhododendron tree on the side of the road is about 20 meters high, the crown towers high on the top of the surrounding trees, clusters of huge flowers bloom freely on the branches, under the sunlight, shining, noble and gorgeous, proud, full of charm, dwarfing all azaleas in the world, and have a strong visual impact and appeal in nature. We came a little late, some azaleas are a little scorched, because this azalea has been blooming for almost a month, during which it is still covered by snow and blown by the wind, but she just laughs at life, everything is light, never easily withers her flowers, and still leaves her beauty at different stages to the world.
Big tree cuckoo
Big tree cuckoo
During the rhododendron bud period of the big tree, clusters of deep purple-red buds stick out from the bracts, towering over the top of the tree, and against the background of the snow, like sparkling rubies, pearlescent and full of nobility. Soon, rose-red flowers bloomed one after another, showing the warmth and exuberance of life. The huge clusters of flowers freely release the nobility, purity and otherworldliness of the Rhododendron King. The birds are also impressed by the charm of the big tree azalea, and come here to suck up the nectar, and the big tree rhododendron also uses this to complete the life events of inheritance. Once pollinated, the flowers will become lighter, and the birds will not come to this flower to eat nectar, leaving the opportunity to other flowers, so that all flowers are evenly wet, so that the fruiting rate of the whole species is significantly improved, and the species can survive for generations in the harsh natural environment.
After the flower is pollinated, in the process of lightening the color, the edges of the petals will slowly be a little scorched, but the flowers of the large tree azalea will not quickly wither because of the scorched edge, but still remain in the branches, her trumpet-shaped corolla also has the final role, to keep the fruit born inside, after all, the place where she grows is high altitude, the temperature is low, and there is rain and snow, hail falling during the period, and the fruit is in the trumpet-shaped corolla, which can be well guaranteed not to be frostbitten by the harsh climate or eaten by some pests. It is not until the fruit inside can cope with the changeable environment outside that the petals of the large tree azalea fall as a whole. The large tree rhododendron capsule is covered with a furry coat, which is also a kind of protection against the bad weather outside. After that, the temperature rises, the rhododendrons begin to germinate and spread their leaves, and by October, the seeds of the rhododendrons ripen one after another, the capsules split, and the seeds are scattered near the mother tree, and once the environment is suitable, the seeds will germinate in large quantities.
Large tree rhododendron, trunk and undertree seedlings
Large tree rhododendron seedlings
Large tree rhododendron seedlings growing on dead tree trunks
The trunk and lower branches of this large tree are covered with green moss, and the trunk diameter is about 60 cm, and in traditional research, it is believed that the large tree rhododendron seeds are small and difficult to reproduce in the wild, so it is difficult to renew the large tree rhododendron at all, but this situation does not exist here. Because of the construction of the Gongdu Highway, the road opens up a channel of light for the trees on both sides, so the large trees here are surrounded by small seedlings, and they are all strong, a big bud is the size of a thumb, a leaf is nearly half a meter, thick and strong, vibrant, and there is no existential crisis at all. Some seedlings grow on dead wood, although they grow slowly, they have not been killed by drought for many years, and they are still struggling to hold on, waiting for the time to run, which makes people feel the greatness of life.