Invasive Tree of Heaven cultivation banned in Poland

The Tree of Heaven (Ailanthus altissima), an invasive alien species originating from East Asia, poses a significant threat to ecosystems in Poland and across the European Union. Due to its aggressive nature, the intentional cultivation, reproduction, and sale of this plant are prohibited in Poland, with potential fines reaching up to one million PLN.

The species is highly adaptable, thriving in drought, pollution, and poor soil conditions. It can grow between 20 and 30 meters tall and produces hundreds of thousands of seeds. Its extensive root system is capable of damaging sidewalks, roads, building foundations, and utility installations. Additionally, the tree releases toxic chemicals known as ailanthone into the soil, which can suppress other vegetation.

While the tree can be mistaken for other species like the staghorn sumac, it is identifiable by its large pinnate leaves that emit a strong, unpleasant odor when crushed. Under Polish nature conservation laws, removing these trees does not require a standard cutting permit. However, experts advise that removal must target the root system to prevent regrowth and that precautions should be taken to protect local wildlife that may use the tree as a habitat.