Handkerchief tree

from Wikipedia, the free encyclopedia
Handkerchief tree
Leaves and flowers of the handkerchief tree

Leaves and flowers of the handkerchief tree

Systematics
Eudicotyledons
Nuclear eudicotyledons
Order : Dogwood-like (Cornales)
Family : Tupelo family (Nyssaceae)
Genre : Davidia
Type : Handkerchief tree
Scientific name of the  genus
Davidia
Baill.
Scientific name of the  species
Davidia involucrata
Baill.

The handkerchief tree ( Davidia involucrata ), also known as the pigeon tree, is the only species of the monotypic plant genus Davidia . The two varieties come from China . The German-language trivial names refer to the large white bracts that hang in the branches like handkerchiefs or, seen from a distance, like a flock of white pigeons. The name "pigeon tree" is also used for the Chinese conifer Cathaya argyrophylla .

description

bark
Illustration of Davidia involucrata var. Vilmoriniana
Male flower
Hermaphrodite inflorescence (blossom)
fruit

Vegetative characteristics

The handkerchief tree is a deciduous tree that reaches heights of growth of up to 20 meters in China and of around 6 to 12 meters in Central Europe, depending on the location. The initially smooth, later scaly bark is light gray-brownish with a reddish inner bark.

The alternate arranged on the branches leaves are arranged in petiole and leaf blade. They resemble linden leaves . The light green to reddish leaf stalks are 3.6 to 7 centimeters long. The simple leaf blade is 8 to 15 centimeters long and 7 to 12 centimeters wide and is ovate to ovate with a more or less heart-shaped base and a pointed to pointed upper end. The pale green underside of the leaf is short and hairy with soft tomentose hair. The leaf margins are serrated to serrated, partly coarsely or sharply serrated. The autumn color is bright golden yellow to orange, reddish.

Generative characteristics

The flowering period extends from April to June. The handkerchief tree is Andromonozoic ; there are male and hermaphrodite, terminal, about 7 centimeters long stalked, spherical inflorescences (flowers) with a diameter of about 2 centimeters on a tree . There are two (rarely three) conspicuous, ovate to elliptic to rundspitzige bespitzte and large thin bracts (bracts) is present, which surround the spherical inflorescences back. The opposite, "handkerchief-like", white bracts are whole-margined to irregularly serrated, pointed to notched and of different sizes; the larger, hanging one is up to 16 cm tall and the smaller one is only about half that size. These bracts appear as soon as they shoot, but remain green and leaf-like for a long time. Only when they become anthesis do they stretch strongly and gradually lose the leafy green until they are finally completely white. The conspicuous, petaloid bracts take on the lookout function instead of the flower envelope and a protective function for the stamens.

The spherical, male inflorescences (groups of stamens ) are without flower cover, the long stamens have purple-white stamens and dark-purple anthers . The spherical hermaphrodite inflorescences consist of a hermaphrodite flower without a flower cover, with a green pistil surrounded by a few shorter stamens and many male flowers with long stamens. Here the stamens have whitish stamens with dark purple anthers. The male and hermaphrodite inflorescences can also be viewed as a single male or hermaphrodite flower. The manhood is less than 10 to 20 years.

Six to ten carpels have grown together to form a subordinate ovary , with one ovule per ovary compartment. The short style ends in a six to ten lobed scar.

The mostly solitary, round to ellipsoidal, finely speckled stone fruits with a fleshy mesocarp , on long, reddish stems , ripen in October, are 3 to 4 centimeters in size and are greenish or reddish-light brown or green-reddish. The orange-brownish, dull and bony stone cores are about 3 centimeters long and about 1.8 centimeters wide, relatively large, ovoid to ellipsoid and deeply longitudinally furrowed. The stone cores contain three to five elongated seeds. The seeds take up to 18 months to germinate and large temperature differences for induction .

The number of chromosomes is 2n = 42.

use

Due to the striking appearance during the flowering period, the pigeon tree is used as an ornamental plant.

This article or paragraph presents the situation in Germany . Help us to describe the situation in other countries.

In Germany, handkerchief trees grow in various parks and botanical gardens . However, the handkerchief tree is only reliably winter hardy in the warmer areas of Germany.

The handkerchief tree thrives best on nutrient-rich, not too dry soils .

Systematics and botanical history

The French lazarist Armand David discovered Davidia involucrata in China in 1868; a herbarium document came to Paris . In honor of David, the genus got its scientific name. It was only 35 years later that the Englishman Ernest Henry Wilson succeeded in collecting the nut-shaped kernels and introducing them to European gardens through the Veitch commercial nursery .

The first description of Davidia involucrata was in 1871 by Henri Ernest Baillon in Adansonia , Volume 10, Pages 114-115 and the genus Davidia was also established.

Davidia involucrata is the only species in the genus Davidia . The classification of this species in a family within the Cornales order has been controversial. For example, some authors put it in a separate family Davidiaceae (Harms) HLLi . At APG IV she is placed in the Nyssaceae family .

In addition to the nominate form , a distinction is made between a variety that is sometimes also viewed as a separate species:

  • Davidia involucrata Baill. var. involucrata ( Syn .: Davidia laeta Dode , Davidia involucrata var. laeta (Dode) Krüssm. ): The nominate form occurs in the Chinese provinces of northern Guizhou , western Hubei , western Hunan , Sichuan and northern Yunnan .
  • Davidia involucrata var. Vilmoriniana (Dode) Wangerin (Syn .: Davidia vilmoriniana Dode ): This variety is native to the Chinese provinces of Guizhou, western Hubei and Sichuan. Almost all specimens planted in Germany belong to this variety. Their characteristics are the narrower and underneath completely bare and light green leaves. The nominate form, on the other hand, has pale green, short and soft-felted hairy leaves underneath.

There are also various cultivars and chimeras with sometimes conspicuously spotted, variegated leaves.

swell

Individual evidence

  1. ↑ Ji-Fan Sun, Shuang-Quan Huang: White Bracts of the Dove Tree (Davidia involucrata): Umbrella and Pollinator Lure? In: Arnoldia. Volume 68, Issue 3, 2011, pp. 2-10, JSTOR 42955494 , PDF at Arnold-Arboretum, Harvard University.
  2. ↑ Dries Vekemans, Tom Viaene et al .: Transference of function shapes organ identity in the dove tree inflorescence. In: New Phytologist. Volume 193, Isue 1, 2012, pp. 216–228, doi : 10.1111 / j.1469-8137.2011.03915.x , (PDF; 2.2 MB) .
  3. ^ Roy Lancaster: Garden Plants for Connoisseurs. Unwin Hyman, 1987, ISBN 978-0-04-440054-7 , p. 27.
  4. ↑ Vít Bojnanský, Agáta Fargašová: Atlas of Seeds and Fruits of Central and East-European flora. The Carpathian ... , Springer, 2007, ISBN 978-1-4020-5361-0 , p. 441.
  5. ^ Davidia involucrata at Tropicos.org. In: IPCN Chromosome Reports . Missouri Botanical Garden, St. Louis
  6. ^ Davidia involucrata at Tropicos.org. Missouri Botanical Garden, St. Louis, accessed October 29, 2018.
  7. ↑ Alan Mitchell: The forest and park trees of Europe: An identification book for dendrologists and nature lovers . Paul Parey, Hamburg and Berlin 1975, ISBN 3-490-05918-2 (translated and edited by Gerd Krüssmann, English original title: A field guide to the trees of Britain and Northern Europe ). P. 374.
  8. ↑ Laurence C. Hatch, Mark Summers, J. Abrici: International Register of Ornamental Plant Cultivars. Open Registration Of Cultivars; OROC Book VIII: Woody Plants , TCR Press, 2017.

Web links

Commons : Handkerchief tree ( Davidia involucrata )  - album with pictures, videos and audio files