Davidia involucrata

Leaves and flowers of the handkerchief tree

The handkerchief tree ( Davidia involucrata ), also called birds in the tree, is the only species of the monotypic genus Davidia. This deciduous tree native to China. The German trivial name takes with respect to the large white bracts, which is also like a flock of white doves in the branches hang like handkerchiefs or seen from a distance. The name "Dove Tree " is also used for the Chinese conifer Cathaya argyrophylla.

The French Lazarist Armand David discovered Davidia involucrata 1868 in China; a voucher specimen came to Paris. It was not until 35 years later succeeded the Englishman Ernest Henry Wilson to collect the nut- shaped cores and introduce them on the market garden Veitch in European gardens. David in honor of the genus got its scientific name.

Occurrence

The home of the handkerchief tree is located in the Chinese provinces of Sichuan and Hubei. The Davidia involucrata var vilmoriniana variety (see section systematics) is native only to Sichuan.

Due to the striking appearance during the heyday of the birds in the tree is a popular ornamental tree. In Germany handkerchief trees grow in various parks and botanical gardens. The handkerchief tree, however, is reliably hardy only in the warmer regions of Germany.

The handkerchief tree prefers nutrient-rich, not too dry soil.

Description

The handkerchief tree is a deciduous tree, the heights of growth in China of up to 20 meters, achieved in Central Europe depending on the location of about 6 to 12 m. The alternate, stalked, simple leaves resemble lime leaves. The red petioles are 3,6 and 7 cm long. The broadly ovate leaf blade is 8-15 cm long and 7-12 cm wide. The lower leaf surface is hairy silky. The leaf edges are serrated to cut.

The flowering period extends from April to June. The handkerchief tree is monoecious; it come to a tree in front of male, female and hermaphrodite flowers. There shall be terminated, 7 cm long stalked inflorescence; there are balls with a diameter of about 2 cm, which have usually two ( rarely three ) bracts ( bracts ). The opposite, " handkerchief -like " white bracts are entire or cut and vary in size: the larger, hanging is up to 16 cm tall and the smaller one is only about half as large. The inconspicuous male flowers do not bloom. Male and hermaphrodite flowers contain from one to seven stamens with purple anthers. Female and hermaphrodite flowers have small, unevenly-sized bloom. Adhesions from six to ten carpels form an inferior ovary with one ovule per ovary compartment. The short style ends in a six-to zehnlappigen scar. The hermaphrodite flowers are only in the upper part of the inflorescence.

The maturing in October, usually solitary standing stone fruits have a size of 3 to 4 cm × 1.5 to 2cm and are purplish - green or light brown. They contain three to five seeds. Seeds require up to 18 months to germinate, while large temperature differences for induction.

System

This species is found in some authors in their own family Davidiaceae ( Harms ) HLLi, such as Arthur John Cronquist An Integrated System of Classification of Flowering Plants, 2nd edition 1988.

In addition to the nominate one variety still a distinction that is sometimes regarded as a separate species.

• Davidia involucrata var involucrata ( Syn: Davidia laeta Dode, Davidia involucrata var laeta ( Dode ) Krüssm. ): The nominate is native to the Chinese provinces of Hubei and Sichuan.
• Davidia involucrata var vilmoriniana ( Dode ) Wangerin ( Syn: Davidia vilmoriniana Dode ): This variety is native to the Chinese province of Sichuan. Almost all planted in Germany specimens belong to this variety. Their characteristic are under the hand perfectly bald and shiny bright green leaves. The nominate other hand, has the under side densely hairy and therefore acting white sheets.

Swell

• Haining Qin & Cham Long Phengklai: Nyssaceae in Flora of China, Volume 13, page 301: species and genus - Online.
• The nature than his own family at DELTA.
• Helmut Pirc: Trees of AZ, Eugen Ulmer Verlag, Stuttgart 2004, ISBN 3-8001-4577-4