The Thorn Tree is a type of tree that grows in the Poison Forest biome.
The Thorn tree is colored like a jungle tree with orangeish spots, and greenish vertical streaks on the west side. Thorn wood trees usually have spiked vines, giving the tree it's name. Like jungle trees, and as of 1.7.2, spruce trees, Thorn trees can be grown to a larger form if arranged in a 2x2 pattern and having bonemeal applied to them.
In it's natural biome, the Thorn Tree is extremely important, and is directly linked to the spawning process of Thorn Bugs, Spore pods and Aggressive plants. In the poison forest, Thorn trees may occasionally generate in large form, or grow on their sides.
Thorn leaves appear swamp green, with dark teal patches. Spiked Vines often generate on Thorn trees. Thorn Trees can be spread by Spore Pods, rolling mushroom block mobs which leave thorn tree saplings behind, and these mobs will spawn near the thorn trees in Poison forests.
It is recommended that these trees be lit ablaze to prevent invasion of the Poison Forest Biome, as these trees are highly invasive, spreading through Spore Pods, and can block out light and spawn hostile mobs.