Skip to main content

Princess tree

(Paulownia tomentosa)

Photo of princess tree
Photo credit: Leslie J. Mehrhoff, University of Connecticut, Bugwood.org

A rapidly growing tree in the figwort family that gets to be 30-40 feet tall. Young trees look like a pole with leaves branching off of it for the first few years. It is often cut back completely when immature but grows back even taller. Twigs are covered with many white lenticels and the grayish-brown bark is thin and rough with random smooth areas.

Overview

Other names for this plant
  • Common names: empress tree, karritree, kiri, royal paulownia, fox-glove tree, quiri
  • Scientific names: Paulownia imperialis; Bignonia tomentosa
Ecological threat
  • Grows in disturbed areas, rock outcroppings, streambanks, forest edges and roadsides.
  • It can crowd out native trees due to its fast-growing nature.
  • Being used in plantations for timber production.
  • Commonly sold as an ornamental.
 Overview map of prohibited classification in WI
Prohibited (red) counties

Classification in Wisconsin: Prohibited

Species Assessment Groups (SAG) were assembled to recommend a legal classification for each species considered for NR 40. The recommendation for the princess tree was based upon this literature review [PDF] developed by the department.

Identification

Leaves: Simple, heart-shaped and opposite or whorled. The leaves are very large when the tree is young but get smaller when mature (five to 12 inches long and five to nine inches wide). Leaves also have long petioles and are hairy on both sides of leaves when young becoming smooth on top as the tree matures. Leaves can also be slightly lobed.

Flowers: Lavender with five petals, the bell-shaped flowers are two inches long and occur in long upright clusters. Flowers can look similar to those of foxgloves. Blooms before leaves are produced in the spring and produce a vanilla scent.

Fruits & seeds: Capsules are formed in clusters and have an oval shape. The capsules start off light green in the summer and are sticky turning tan and drying in the winter. Each capsule contains up to 2,000 winged seeds that are readily dispersed by wind and water.

Roots: Roots can grow up to 15 feet in one season and have adventitious buds that can survive fire and mowing.

Similar species: Catalpa spp. (C. speciosa, C. bignonioides) have very similar shaped leaves but have flowers that are white and produce long slender bean-like seedpods.

Distribution

Currently, there have been no reports of princess tree in Wisconsin. Have you seen it? Send us a report.

Control

Mechanical: Seedlings can be hand-pulled.

Chemical: Cutting or girdling followed by an application of glyphosate or triclopyr; basal bark with triclopyr.

Photos

View princess tree pictures in our photo gallery.

Resources

Sources for content
  • Czarapata, Elizabeth; Invasive Plants of the Upper Midwest: an illustrated guide to their identification and control. University of Wisconsin Press. 2005. Pg. 124
  • Invasive Plant Atlas of New England: Princess tree [exit DNR].
  • Remaley, Tom. Plant Conservation Alliance Factsheet: Princess tree [exit DNR]. Last updated July 7, 2009.
Links for more information