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
Princess tree is an
aggressive ornamental tree that grows rapidly in disturbed natural areas,
including forests, streambanks, and steep rocky slopes.
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
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.
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
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. Seedlings grow
quickly and flower in 8-10 years. Mature trees are often structurally
unsound and rarely live more than 70 years.
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
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.
Cut stump application
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
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 WEB SITE DOES NOT CONSTITUTE ENDORSEMENT OF ANY MATERIAL.
For more information on
the management of Princess Tree, please contact:
- Kris Johnson, Great Smoky Mountains
National Park, Gatlinburg, TN
SUGGESTED ALTERNATIVE PLANTS
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
Tom Remaley, Great Smoky Mountains National
Park, Gatlinburg, TN
Jil M. Swearingen, National Park Service, Washington,
Alison Dalsimer, Consultant, Legacy Resource
Management Program, Washington, DC
Tom Remaley, Great Smoky Mountains National
Park, Gatlinburg, TN
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