These subtropical forests consists mostly of deciduous trees who lose their leaves in dry season. They depend on the annual monsoon climate. Apart from Indochina and the Lesser Sunda Islands they thrive in parts of India, Africa and Latin America, often bordering tropical rainforests. The formerly huge and connected deciduous monsoon forests in Indochina, namely in Thailand, Laos and Burma/Myanmar, have been mostly destroyed while the remains are heavily fragmented. This forest type is also known as 'tropical and subtropical dry broadleaf forest'.
Unlike in the tropical rainforests, the trees in deciduous monsoon forests don't grow that high and don't evolve as many layers as are in those. The highest layer reaches between 25m and 35m, and the canopy is thinner, what allows a more livens underwood. The biodiversity in a monsoon forest is usually smaller than in rainforests. Moreover, the ground is dryer and, due to seasonal and months-long dry periods following the monsoon cycle, most of the trees shed their leaves then to reduce moisture loss. Others, more exceptionally, who grow at sites with access to year-around ground water or at moist sites remain evergreen. Monsoon forests are mixed-forests. However, in Indochina the teak tree is typical for coining these forests.
The Indochinese monsoon forests are home for a great number of plants and animals. Among them are large cats like tigers and leopards, monkeys of different kinds like gibbons, deer, plenty of birds species, rodents and reptiles. Also elephants appear, where they could survive.
Towards the equator deciduous monsoon forests are often transforming into tropical rainforests, while towards the other side they often change into savannah and grassland, particularly when the regions there are dryer.
Deciduous monsoon forests are under threat worldwide. In Indochina logging started in the 19th century, when Britain conquered step by step the territories of Burma. In the 1880s, British logging companies entered Lanna and built roads to gain access to the then still huge and old teak forests there. Logging, both legal and illegal, grew in the 20th century and led widely to the deforestation of north Thailand. In the last decades the monsoon forests of Laos and Burma/Myanmar fell victim to the same process.
Apart from the commercial exploitation are human encroachement with the transfer of forest into acreage, fire and arson and the climate change causes for the decline of deciduous monsoon forests. Seeing the large remaining forest in the Greater Golden Triangle burning excessively every year in grand-style, it's obvious that they are very vulnerable to arson in the long months of dry-season.
This article is based on decades of practical experiences and observations. Moreover it's based on a number of publications. You find a list of them on the Literature page. However, it's not at all exhausting; it comes together with uncounted articles from newspapers, magazines, (qualified) websites and movies, both fiction and documentary. Sometimes, a good talk with a connoisseur of a certain topic provides me with facts, ideas, inspirations and innovations and/or reveals a mistake.