Thursday, May 28, 2009

Royal Paulownia: The Perfume of Spring Along the Hudson

When May roses begin to perfume the air violet blooms burst forth on Royal Paulownias that grow along the edge of the Hudson River. There is no time to mourn fading purple lilacs when the trumpet-like clusters of Paulownia tomentosa release their fragrance. Their scent reveals a riverside terroir that smells ozonic, vanillic, powdery and almond-like. The fragrance is most prominent when dusk arrives. That is also the time when people who never look up at the towering trees recognize the source of their olfactive pleasure. Few people, however, know the folklore behind these trees and how they became naturalized in the United States.

Paulownia tomentosa is also known as the Empress or Princess Tree. The genus Paulownia is named in honor of Anna Pavlovna (Paulowna by Dutch transliteration), the daughter of Czar Paul I. In China it is customary to plant an Empress Tree when a baby girl is born. The maturity of the tree and the girl coincide. When she is eligible for marriage the tree is cut down to make a wedding chest. The presence of an Empress Tree near a home is considered good luck as it is said to be favored by the mythical Phoenix who is drawn to its branches. In Japan, if a Paulownia drops its leaves early in the season, it is considered bad luck. During World War II the United States dropped paper Paulownia (Kiri) leaves on Japan that included ominous propaganda meant to play on the "bad luck" folklore attached to the leaves of the tree.

In the mid 1800s Chinese porcelain was transported by train in the United States. The materials used to pack these delicate objects were Paulownia seed pods. Each pod contains up to 2000 small-winged seeds and resembles a giant pistachio nut. Some seeds escaped during transit while others were released at their destination and carried by the wind. It is likely that Chinese porcelain making its way down the New York Central Railroad is responsible for the Paulownia trees along the Metro North Hudson Line.

Though Paulownia tomentosa is considered an invasive species that escaped cultivation it possesses a delicate nature and is particularly sensitive to weed killers and pesticides. It can also tolerate high salinity and drought. This makes portions of the Hudson River shoreline ideal for a tree that can reach up to 15 feet in one season and 30 feet in three years. When Paulownias are in bloom their scent is carried by the wind along the Hudson River, perfuming the shoreline and mesmerizing anyone fortunate enough to participate in a landscape that includes them.

Givaudan's Roman Kaiser analyzed the scent of Paulownia tomentosa flowers in 1995. When Glass Petal Smoke asked him if there was a little heliotropin in the mix Kaiser responded with scientific precision, “This heliotropin related note is mainly generated by the interaction of the main constituent hydroquinone dimethyl ether with beta-ionone including derivatives and methyl cinnamate. Methyl benzoate, methyl salicylate and methyl 2-methoxybenzoate round this accord off.” Heliotropin is a molecule found in vanilla and smells floral, vanillic, and slightly almond-like (there is a lot of heliotropin in Tahitian vanilla beans). Kaiser’s complete analysis of Paulownia tomentosa is as follows:

Methyl 2-Methybutyrate 0.10
Methyl Caproate 0.10
(E)-Ocimene 0.60
6-Methyl-5-Hepten-2-One 0.30
Nonanal 0.05
Benzaldehyde 0.05
Linalool 0.05
Cyclic-Beta-Ionone 0.10
Methyl Benzoate 5.50
(E)-Beta-Farnesene 0.20
Hydroquinone Dimethyl Ether 79.00
Methyl Salicylate 1.90
Dihyro-Beta-Ionone 1.20
Benzyl Alcohol 0.80
Beta-Ionone 6.00
Methyl- (E)-Cinnamate 0.90
Methyl2-Methoxybenzoate 2.70
Benzyl Benzoate 0.10

Total: 99.65

Hudson River painting of Royal Paulownia by Jamie Williams Grossman. All rights revert back to the artist.

Photos of Paulownia seed pods from the Oregon State Department of Horticulture .

Some of the fragrance ingredients in Roman Kaiser's analysis of Paulownia tomentosa can be found on Givaudan's website by clicking here. You can cut and paste the name of the molecule to research it. The Good Scents Company has an extensive database of raw materials. Perhaps we will see this kind of organoleptic information democratized in Wolfram/Alpha as the new search engine develops its très cool chemistry section.

Analysis of fragrance molecules is conducted by gas chromatography-mass spectrometry (also known as "GC mass spec" in the fragrance business). The machine analyzes scent, but requires the technical and olfactive skills of a trained professional for optimal results.