Tree of heaven is among the most aggressively invasive trees in eastern North America. Native to central China and introduced to the United States in 1784 as an ornamental and potential silkworm food source, it has since naturalized across the entire country, concentrating heavily in the Mid-Atlantic, Northeast, and Pacific Coast. It thrives in disturbed soils — roadsides, vacant lots, fence lines, railway corridors — and will grow in conditions that defeat almost every native tree: compacted fill, urban concrete margins, rock outcroppings.
The tree is allelopathic, producing a compound called ailanthone that is toxic to surrounding plant roots and suppresses germination of competing species. A healthy bed near an established tree will progressively deteriorate as the roots spread. It also resprouts vigorously from cut stumps and severed roots, meaning improperly handled removal makes the problem worse. The correct approach is to cut, immediately apply concentrated triclopyr or glyphosate to the cut surface while still wet, and monitor for resprouts.
Its most urgent significance in this region is as the primary breeding host of spotted lanternfly (Lycorma delicatula). Ailanthus stands function as population reservoirs — lanternfly densities on tree of heaven can be extraordinary, with hundreds of adults per tree — and the insects disperse from these sites to attack grapevines, fruit trees, and ornamentals. Eliminating Ailanthus from a property is the single most effective structural action against lanternfly pressure.