Tree of Heaven: Identification and Management

The Tree of Heaven (Ailanthus altissima) is a tall, invasive tree reaching up to 25 m. It features smooth, grey young bark with pale striations, becoming rougher and darker with age. Toxic compounds in bark and leaves suppress nearby plant growth via allelopathy. Leaves are compound, 30–60 cm long, oddly pinnate with 9–25 pointed, ovate to lanceolate leaflets. Crushed leaves emit a foul odor from basal glands. Flowers, 5–8 mm, appear June–August in large panicles, initially dark red, later greenish-white. Fruits are twisted samaras, 4 cm long, ripening from yellowish-green to bright orange-red, forming dense clusters. Report sightings via VERA app or waarneming.nl. Inspect and clean equipment after work in infested areas. Image set includes blooming specimens, leaf close-ups, and detailed leaf structures.