An imperial collection of trees
At an elevation of 1,000 meters in the Shan Highlands, the Pyin Oo Lwin Botanical Gardens is a living database of a bygone era. Established in 1915 by Alex Roger, a British Forest Officer, the site was originally named the Maymyo Botanical Gardens. It was explicitly modeled after the Royal Botanic Gardens, Kew, in London, and served as a collection hub for flora from across the British Empire. The initial 177-hectare park contains 514 species of indigenous trees and 74 foreign species, brought together for study and acclimatization.
The garden's location in the former colonial hill station of Maymyo provided a cool climate suitable for cultivating a wide range of temperate and sub-tropical plants. By 1920, foresters had planted nearly 5,000 trees, focusing on pine varieties, alongside 575 different floral species. This collection includes various oaks, pines, and eucalyptus trees whose origins are to imperial territories. Because these specimens were planted over a century ago, they represent a genetic snapshot of their original native environments—environments that have often been drastically altered or destroyed since the early 20th century.
Living genetic archives
Colonial-era botanical gardens are now accidental genetic arks. The trees planted decades or centuries ago can harbor genetic diversity that no longer exists in their native habitats. DNA profiling, similar to the techniques used in criminal cases or paternity tests, allows scientists to generate a unique genetic fingerprint for each tree. By comparing the DNA of these century-old trees with that of their modern wild relatives, researchers can identify unique genetic markers and measure the genetic diversity that has been lost over time.
This analysis provides a baseline for modern conservation. The genetic information extracted from the Pyin Oo Lwin trees can reveal the ancestry of specific populations and identify genes related to disease resistance or environmental adaptation. For species like the American chestnut, which was decimated by blight, crossbreeding with surviving historic specimens or their genetically resistant relatives is a primary conservation strategy. The garden's trees, therefore, are old plants; they are reservoirs of genetic information from populations that may now be extinct, providing a plan for potential restoration efforts. The study of ancient and historical plant DNA, a field known as archaeogenomics, uses these living collections to reconstruct the evolutionary history of forests and their adaptation to changing climates.