Tree of Heaven

Tree of Heaven, scientifically known as Ailanthus altissima, is an invasive plant species that originated in China and was introduced to other parts of the world as an ornamental tree. It is also commonly referred to as "ailanthus," "copal tree," or "paradise tree." Despite its appealing name, the Tree of Heaven has become a problematic and aggressive invasive species in many regions.

Characteristics

• Appearance: Tree of Heaven is a deciduous tree that can reach heights of up to 80 feet (24 meters) or  more. Its compound leaves are large, typically measuring 1-4 feet (30-120 centimeters) long, with 10-40 leaflets per leaf. The leaflets are lance-shaped with serrated edges and emit a distinctive odor when crushed.
• Growth habit: This tree has a rapid growth rate and can quickly colonize disturbed areas. It has a unique ability to sprout vigorously from its roots, stumps, and even broken branches, making it difficult to eradicate once established. The roots can penetrate deep into the soil and produce suckers that form new trees.
• Reproduction: Tree of Heaven produces large clusters of small, greenish-yellow flowers in early summer. Female trees produce large quantities of winged seeds called samaras, which are dispersed by wind over long distances. A single female tree can produce thousands of seeds each year, further aiding its spread.

Impacts

It is highly invasive and outcompetes native plant species by releasing chemicals that inhibit their growth. It can form dense thickets, shading out other plants and reducing biodiversity. Its ability to adapt to a wide range of soil conditions, including poor and contaminated soils, further contributes to its invasive success.

Control and management

• Controlling the spread of Tree of Heaven can be challenging due to its ability to resprout from root fragments and extensive seed production. The most effective approach is a combination of mechanical removal (cutting and uprooting), followed by herbicide application to prevent regrowth. Regular monitoring and follow-up treatments are often necessary to achieve long-term control.
• Health concerns: Some individuals may develop an allergic reaction to the tree's sap or airborne pollen, resulting in skin irritation or respiratory issues. It is advisable to wear protective clothing and take precautions when working near Tree of Heaven.

Prevention and Awareness

• Early detection, prevention of seed production, and prompt eradication are essential in minimizing its spread and mitigating its ecological and economic consequences.