Airborne operations are particularly dangerous and full of risk, paratroopers have higher acceptable casualty rates than other operations. Open fields are preferable to wooded areas, but sometimes logistical and geographic concerns do not permit such easy access. The British Special Air Service is credited with first deliberately jumping into forests with the intention of landing in trees and abseiling from them.
During the Malayan Emergency, Commonwealth Forces were pitted against the Malayan National Liberation Army who benefitted from the thick cover the rainforest provided. Long range patrols were ineffective and taxing for the Commonwealth. They elected to drop troops directly into the thickest parts of the jungle, carrying hundreds of feet of rope, knowing they would get stuck in the canopy. They would tie their rope to the tree and rappel down. Most parachutes did not survive a tree landing but it proved to be an effective way of inserting troops as close as possible.
The United States Army does have one company trained in tree jumping, the Rough Terrain Airborne Operations Fort Bragg.