Invasive Princess Tree

Princess tree (Paulownia tomentosa) is a fast-growing 30-60 foot deciduous tree native to China that spreads by releasing thousands of tiny winged seeds in the fall. It’s considered invasive and is banned in Connecticut. It is illegal to import, move, sell, purchase, transplant, cultivate or distribute.

Also called Empress Tree and Royal Paulownia, it was named after Anna Pavlovna, the daughter of Czar Paul I.

It was brought to Europe in the 1834 by the Dutch East India Company and made it to North America in 1844. The seeds were used as packing material by Chinese porcelain exporters before the advent of polystyrene. It was reportedly touted as a wonder tree in the Sunday newspaper supplements of the day.

Princess tree is highly adaptable. It’s tolerant of drought, pollution and infertile or acidic soils. According to the National Park Service, “Its ability to sprout prolifically from adventitious buds on stems and roots allows it to survive fire, cutting and even bulldozing in construction areas.”

As the flowers bear male and female organs, the empress tree is considered hermaphroditic.

It’s commonly mistaken for native Northern catalpa (Catalpa speciosa) but is easily told apart because of its opposite leaves, flowers and fruit.

The Problem
Princess tree infests roadsides, stream banks, forest edges and even some rocky habitats, displacing native species. The seeds are spread by wind and water. Each tree may produce as many as 20 million seeds and it can also regenerate from roots and stems.

Identification
• White lenticels are prominent on younger branches and twigs.
• Oval or heart-shaped leaves are hairy, arranged oppositely and can reach up to a foot across. They can be twice as long on juvenile trees and may two have small secondary lobes.
• The 2-inch-long pale violet flowers are fragrant and held in showy upright panicles up to a foot long that appear before the leaves. The flowers have stripes on the inside of the corolla. Some say they look like foxglove flowers.
• The egg-shaped fruit capsules turn from light green to dark brown and persist until spring. The 2-inch-long fruits have four compartments containing 2000 small winged seeds. Spent capsules may remain on the tree through the winter.

Native Alternatives
• American Holly (Ilex opaca)
• Flowering Dogwood (Cornus florida)
• Northern Catalpa (Catalpa speciosa)
• Redbud (Cercis canadensis)
• Sassafras (Sassafras albidum)
• Serviceberry (Amelanchier arborea)

Control
• Young plants can be pulled. Make sure to get the roots.
• For larger specimens triclopyr or glyphosate can applied to cut stumps or bark. Follow label instructions … the label is the law.
• Repeated cutting will eventually exhaust the plant.
• Have a restoration plan. Disturbance without replanting can result in the return of the same invasive (or other invasive species).

For more information visit the Connecticut Invasive Plant Working Group’s website at cipwg.uconn.edu

– Compiled by Will Rowlands