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Plant Conservation Alliance®s Alien Plant Working Group 

Xeeds HoneXild: Alien Plant Invaders of Natural Areas 

http://www.nps.gov/plants/alien/

FACT SHEET: PRINCESS TREE

Princess Tree 

Paulownia tomentosa (Thunb.) Sieb. & Zucc. ex Steud. 

Figwort family (Scrophulariaceae) 

NATIVE RANGE 

China 

DESCRIPTION 

Princess tree, also known as royal paulownia or empress tree, is a small to 

medium sized tree that may reach 30-60 feet in height. The bark is rough, 

gray-brown, and interlaced with shiny, smooth areas. Stems are olive-brown to 

dark brown, hairy and markedly flattened at the nodes (where stems and 

branches meet). Leaves are large, broadly oval to heart-shaped, or sometimes 

shallowly three-lobed, and noticeably hairy on the lower leaf surfaces. They 

are arranged in pairs along the stem. Conspicuous upright clusters of showy, 

pale violet, fragrant flowers open in the spring. The fruit is a dry brown capsule 

with four compartments that may contain several thousand tiny winged seeds. 

Capsules mature in autumn when they open to release the seeds and then 

remain attached all winter, providing a handy identification aid. 

ECOLOGICAL THREAT 

Princess tree is an aggressive ornamental tree that grows rapidly in disturbed 

natural areas, including forests, streambanks, and steep rocky slopes. 

DISTRIBUTION IN THE UNITED STATES 

Princess tree is found in 25 states in the eastern U.S., from Maine to Texas. 

HABITAT IN THE UNITED STATES 

Princess tree can be found along roadsides, streambanks, and forest edges. It 

tolerates infertile and acid soils and drought conditions. It easily adapts to 

disturbed habitats, including previously burned areas, forests defoliated by 

pests (such as the gypsy moth) and landslides and can colonize rocky cliffs 

and scoured riparian zones where it may compete with rare plants in these 

marginal habitats. Its ability to sprout prolifically from adventitious buds on 

stems and roots allows it to survive fire, cutting, and even bulldozing in 

construction areas. 

BACKGROUND 

Princess tree was introduced into the U.S. as an ornamental and landscape tree around 1840. It was first imported to 

Europe in the 1830's by the Dutch East India Company and brought to North America a few years later. This tree has 

since become naturalized in the eastern U.S. and is also grown on the west coast. Princess tree is native to western and 

central China where historical records describe its medicinal, ornamental, and timber uses as early as the third century 

B.C. It was cultivated centuries ago in Japan where it is valued in many traditions. Recently it has also been grown in 

plantations and harvested for export to Japan where its wood is highly valued. 

BIOLOGY & SPREAD 

Princess tree can reproduce from seed or from root sprouts; the latter can grow more than 15 feet in a single season. The 

root branches are shallow and horizontal without a strong taproot. Seed-forming pollen is fully developed before the onset 

of winter and the insect-pollinated flowers open in spring. A single tree is capable of producing an estimated twenty million 

seeds that are easily transported long distances by wind and water and may germinate shortly after reaching suitable soil. 
20 May 2005 Page 2 of 3 

Plant Conservation Alliance®s Alien Plant Working Group 

Xeeds HoneXild: Alien Plant Invaders of Natural Areas 

http://www.nps.gov/plants/alien/

Seedlings grow quickly and flower in 8-10 years. Mature trees are often structurally unsound and rarely live more than 70 

years. 

MANAGEMENT OPTIONS 

Princess tree can be controlled using a variety of mechanical and chemical 

controls. Hand pulling may be effective for young seedlings. Plants should be 

pulled as soon as they are large enough to grasp. Seedlings are best pulled after a 

rain when the soil is loose. The entire root must be removed since broken 

fragments may resprout. Trees can be cut at ground level with power or manual 

saws. Cutting is most effective when trees have begun to flower to prevent seed 

production. Because Princess tree spreads by suckering, resprouts are common 

after cutting. Cutting should be considered an initial control measure that will 

require either repeated cutting of resprouts or an herbicidal treatment. 

Princess tree seedlings and small trees can be controlled by applying a 2% 

solution of glyphosate (e.g., Roundup®) or triclopyr (e.g., Garlon®) and water plus a 0.5% non-ionic surfactant to 

thoroughly wet all leaves. Use a low pressure and coarse spray pattern to reduce damage from spray drift on non-target 

species. Glyphosate is a non-selective systemic herbicide that may kill non-target plants that are only partially sprayed. 

Triclopyr is a selective herbicide for broadleaf species. In areas where desirable grasses are growing , triclopyr can be 

used with minimal non-target damage. 

Girdling is effective on large trees where the use of herbicides is impractical. Using a hatchet, make a cut through the bark 

encircling the base of the tree, approximately six inches above the ground. Be sure that the cut goes well below the bark. 

This method will kill the top of the tree but resprouts are common and may require a follow-up treatment with a foliar 

herbicide. 

The cut stump method, that is applying herbicide to freshly cut stumps, should be considered for individual trees or when 

desirable plants are nearby that might be impacted by foliar applications. Stump treatments can be used as long as the 

ground is not frozen. Begin treatments by horizontally cutting stems at or near ground level. Immediately apply a 50% 

solution of glyphosate or triclopyr and water to the cut stump making sure to cover the outer 20% of the stump. Basal bark 

applications are effective throughout the year as long as the ground is not frozen. Apply a mixture of 25% triclopyr and 

75% horticultural oil to the base of the tree trunk to a height of 12-15 inches from the ground. Thorough wetting is 

necessary for good control; spray until run-off is noticeable at the ground line. 

USE PESTICIDES WISELY: Always read the entire pesticide label carefully, follow all mixing and application instructions and wear all 

recommended personal protective gear and clothing. Contact your state department of agriculture for any additional pesticide use 

requirements, restrictions or recommendations. 

NOTICE: mention of pesticide products on this page does not constitute endorsement of any material.

CONTACTS 

For more information on the management of Princess Tree, please contact: 

• Kris Johnson, Great Smoky Mountains National Park, Gatlinburg, TN 

SUGGESTED ALTERNATIVE PLANTS 

Many native shrubs and trees make excellent alternatives to Princess tree. Examples include serviceberry (Amelanchier 

canadensis and A. arborea), redbud (Cercis canadensis), flowering dogwood (Cornus florida), American holly (Ilex 

opaca), red mulberry (Morus rubra), spicebush (Lindera benzoin), and sassafras (Sassafras albidum). Contact the native 

plant society in your state for additional recommendations and for information on local sources of native plants. 

OTHER LINKS 

• http://www.invasive.org/search/action.cfm?q=Paulownia%20tomentosa 

• http://nbii-nin.ciesin.columbia.edu/ipane/icat/browse.do?specieId=83
20 May 2005 Page 3 of 3 

Plant Conservation Alliance®s Alien Plant Working Group 

Xeeds HoneXild: Alien Plant Invaders of Natural Areas 

http://www.nps.gov/plants/alien/

AUTHOR 

Tom Remaley, Great Smoky Mountains National Park, Gatlinburg, TN 

EDITORS

Jil M. Swearingen, National Park Service, Washington, DC 

Alison Dalsimer, Consultant, Legacy Resource Management Program, Washington, DC 

PHOTOGRAPHS 

Tom Remaley, Great Smoky Mountains National Park, Gatlinburg, TN 

REFERENCES 

Cunningham, T.R., S.B. Carpenter. 1980. The effect of diammonium phosphate fertilizer on the germination of Paulownia 

tomentosa seeds. Tree Planter's Notes 31:6-8. 

Hu, Shiu-Ying. 1959. A monograph of the genus Paulownia. Quarterly Journal of the Taiwan Museum 7(1&2):1-54. 

Langdon, K.R., K.D. Johnson. 1994. Additional notes on invasiveness of Paulownia tomentosa in natural areas. Natural 

Areas Journal 14 (2):139-140. 

Melhuish, J.H., Jr., C.E. Gentry, P.R. Beckjord. 1990. Paulownia tomentosa seedling growth at differing levels of pH, 

nitrogen, and phosphorus. Journal of Environmental Horticulture 8:205-207. 

Niemeier, J. 1984. I had to kill the empress. Arbor Bulletin Arbor Foundation Seattle University Washington 47(2):21-23. 

Petrides, G.S. 1972. A field guide to trees and shrubs. The Peterson Field Guide Series. 2nd ed. Boston: Houghton Mifflin 

Co. 

Rehder, M.A. 1927. Manual of cultivated trees and shrubs. MacMillan Co., New York. (Reprinted 1983): Dioscorides 

Press, Portland, Oregon. Sand, S. 1992. The empress tree. American Horticulturist 71:27-29. 

Sanderson, K.C. 1972. Effect of photoperiod on the growth of empress tree, Paulownia tomentosa seedlings. Alabama 

Agriculture Experiment Station Hort. Service 18:10-11. 

Sticker, O., M.F. Lahloub. 1982. Phenolic glycosides of Paulownia tomentosa bark. Journal of Medicinal Plant Research 

46:145-148. 

Swanson, R.E. 1994. A field guide to the trees and shrubs of the southern Appalachians. Baltimore: Johns Hopkins Univ. 

Press. 

Swearingen, J. 2009. WeedUS Database of Plants Invading Natural Areas in the United States: Princess Tree (Paulownia 

tomentosa). http://www.invasive.org/weedus/subject.html?sub=2426. 

USDA, NRCS. 2009. The PLANTS Database (http://plants.usda.gov). National Plant Data Center, Baton Rouge, LA 

70874-4490 USA. 

Williams, C.E. 1983. The exotic empress tree, Paulownia tomentosa: an invasive pest of forests. Natural Areas Journal 

13(3):221-222.