Paulownia is a genus of between 6–17 species (depending on taxonomic authority) of plants in the monogeneric family Paulowniaceae, related to and sometimes included in the Scrophulariaceae. They are native to much of China (its name in Chinese is 泡桐, pinyin: pàotóng), south to northern Laos and Vietnam, and long cultivated elsewhere in eastern Asia, notably in Japan and Korea. They are deciduous trees 40–50ft tall, with large leaves 15–40 cm across, arranged in opposite pairs on the stem. The flowers are produced in early spring on panicles 10–30 cm long, with a tubular purple corolla resembling a foxglove flower. The fruit is a dry capsule, containing thousands of minute seeds.
Paulownia fortunei is a fast-growing tree that is grown commercially for the production of hardwood timber.
Testing by CSIRO in Australia has shown that Paulownia wood is very attractive for wood-boring insects. Paulownia species are also used as food plants by the larvae of some Lepidoptera species including Endoclita excrescens.
Paulownia is known in Japanese as kiri (桐), specifically referring to P. tomentosa; it is also known as the "princess tree". It was once customary to plant a Paulownia tree when a baby girl was born, and then to make it into a dresser as a wedding present when she gets married. Paulownia is the mon of the office of prime minister and also serves as the emblem of the cabinet and the government (vis-à-vis the chrysanthemum being the Imperial Seal of Japan). It is one of the suits in hanafuda, associated with the month of December. Japan: An Illustrated Encyclopedia (page 1189; Tokyo: Kodansha, 1993. ISBN 4-06-931098-3) states:
The fine grained soft and warp resistant properties also make Paulownia wood exceptionally suited for making wooden surfboards. Tom Wegener and more recently "Empress Surfboards" are amongst the shapers who pioneered its use. Unlike those made from balsa wood, the resulting surfboards do not need to be glassed.
More recently, it is used as body material for high end custom guitars . The appearance , resonance and light weight make it a highly sought after tone wood for guitar makers.
Paulownia is extremely fast growing; some species of plantation Paulownia can be harvested for saw timber in as little as five years. Once the trees are harvested, they regenerate from their existing root systems, earning them the name of the"Phoenix tree." Paulownia has the ability to reclaim ecologically stressed and degenerate patches of land relatively quickly. Its root systems run deep and penetrate compacted and contaminated soils which have resulted from industrialized development. Paulownia is a phyto-remediator, increasing the organic content of degraded soils, processing and filtering contaminants through the uptake of its vascular system, and emitting oxygen into the atmosphere.