Princesstree, Paulownia (Paulownia tomentosa)
Miller, J.H., E.B, Chambliss, N.J. Loewenstein. 2010. A Field Guide for the Identification of Invasive Plants in Southern Forests. General Technical Report SRS-119. Asheville, NC. United States Department of Agriculture, Forest Service. 126 p.
Deciduous tree to 60 feet (18 m) in height and 2 feet (60 cm) in diameter with large heart-shaped leaves, fuzzy hairy on both sides, showy pale-violet flowers in early spring before leaves, and persistent pecan-shaped capsules in terminal clusters in summer to winter. Abundant flower buds present on erect stalks over winter.
Twigs and branches stout, glossy gray brown and speckled with numerous white dots (lenticels). No terminal bud. Lateral leaf scars raised, circular, and becoming larger, dark, and sunken. Bark light-to-dark gray, roughened, and becoming slightly fissured. Stem pith chambered or hollow and wood white.
Opposite, heart shaped and fuzzy hairy on both surfaces, 6 to 12 inches (15 to 30 cm) long and 5 to 9 inches (13 to 23 cm) wide. Leaves larger on resprouts, 16 to 20 inches (40 to 50 cm) across, with extra tips often extending from the end of veins. Petioles rough hairy, 2 to 8 inches (5 to 20 cm) long.
April to May. Covered with showy erect panicles of pale-violet flowers before leaves in early spring, tubular with 5 unequal lobes. Fragrant. Flower buds fuzzy, linear, becoming ovoid in summer, and persistent on erect stalks over winter.
Fruit and seeds
June to April. Terminal clusters of pecan-shaped capsules 1 to 2 inches (2.5 to 5 cm) long and 0.6 to 1 inch (1.5 to 2.5 cm) wide. Pale green in summer turning tan and eventually black in winter and persistent into spring. Capsules split in half during late winter, each releasing 1,000s of tiny winged seeds.
Common around old homes, roadsides, riparian areas, and forest margins in infested areas. Infrequently planted in plantations. One tree can produce 21 million seeds per year with 2,000 per capsule. Viable seed can be produced by 5- and 7-yearold plants. Spreads by wind- and water-dispersed seeds. In the mountains, seed can be dispersed up to 2 miles (3 km). Invades after fire, harvesting, and other disturbances. Forms colonies from root sprouts.
Resembles southern catalpa (Catalpa bignonioides Walt.) and northern catalpa [C. speciosa (Warder) Warder ex Engelm.], which have leaves with sparsely hairy upper surfaces and rough hairy lower surfaces and long slender, persistent fruit. Also resembles the invasive paper mulberry [Broussonetia papyrifera (L.) L’Hér. ex Vent.] with somewhat smaller leaves, sandpapery feeling above and white velvety hairy below.
History and use
Introduced in the early 1800s from East Asia. Has been widely planted as an ornamental and grown in scattered plantations for speculative high-value wood exports to Japan.
Found as escaped plants from ornamental plantings throughout the region and as scattered dense infestations along highways and roadsides to move into disturbed forests in MS, TN, KY, and NC, as well as north AL and north GA.
- Do not plant. Remove prior plantings, and control sprouts and seedlings. Bag and dispose of plants and capsules in a dumpster or burn.
- Minimize disturbance within miles of where this plant occurs.
- Treat when new plants are young to prevent seed formation.
- Cut when fruit are not present.
- Manually pull new seedlings and tree wrench saplings when soil is moist, ensuring removal of all roots.
- Burning treatments are suspected of having minimal topkill effect due to scant litter.
Recommended control procedures
Large trees. Make stem injections using Arsenal AC* or when safety to surrounding vegetation is desired, Garlon 3A or a glyphosate herbicide in dilutions and cut-spacings specified on the herbicide label (anytime except March and April). For felled trees, apply these herbicides to stump tops immediately after cutting. Also, ORTHO Brush-B-Gon, Enforcer Brush Killer, and Vine-X are effective undiluted for treating cut-stumps and available in retail garden stores (safe to surrounding plants).
Saplings. Apply a basal spray of Garlon 4 as a 20-percent solution (5 pints per 3-gallon mix) in a labeled basal oil product, or apply undiluted Pathfinder II when safety to surrounding vegetation is desired. Elsewhere, apply Stalker* as a 6- to 9-percent solution (1.5 to 2 pints per 3-gallon mix) in a labeled basal oil product, vegetable oil, kerosene, or diesel fuel (where permitted).
Resprouts and seedlings. Thoroughly wet all leaves with one of the following herbicides in water with a surfactant (July to October): Arsenal AC* as a 0.75-percent solution (3 ounces per 3-galllon mix); Arsenal PowerLine* as a 1.5-percent solution (6 ounces per 3-gallon mix); or when safety to surrounding vegetation is desired, a glyphosate herbicide, Garlon 3A, or Garlon 4 as a 2-percent solution (8 ounces per 3-gallon mix).
* Nontarget plants may be killed or injured by root uptake.