The pristine trees of a silk road poplar forest
The Populus Euphratica or Hero Tree…
Poplar trees are dioecious (self-propagating) plants that produce globular pollen that take root when they meet water. They also have heteromorphism (i.e. the character of the leaves changes with the age of the tree) and an extensive root network with strong ability to absorb water and withstand salt. The trees grow fast when there is enough water and the growth rate decelerates when the water resource is scanty.
Fossils of this kind of poplar tree have been discovered in the strata of the Tertiary Oligocene located at Kuqa Thousand-joss Cave and Dunhuang Blacksmith Grove. These fossils are about 3-6 million years old. These fossil trees have physiological characteristics that make them very hardy, enabling them to withstand both chilling winters and broiling summers, aridity, waterlogging and high saline-alkali concentrations.
There is an old saying that poplar trees can thrive for 1000 years, stand firmly for 1000 years after their death and fail to rot after falling down.
The Tarim Basin is the world’s core area of these poplar trees which cover 352,200 ha, accounting for 90% of their total area in China and 54.29% of the global distribution. The largest natural poplar trees in the world occur in the Tarim River drainage area and large areas of undisturbed poplar forests have been preserved in this region.
Poplar trees date from the Tertiary and, therefore, have been regarded as living fossils of ancient species by botanists. They bear genes that endows them with the adaptation to withstand chilling winters and broiling summers, aridity and waterlogging, saline-alkali concentrations. Thus, these ancient rare trees, which possess great resilience, can be regarded as an invalauble natural gene pool.