Platanus

Jump to navigation Jump to search
style="background:#Template:Taxobox colour;"|Platanus
Leaves and fruit of a London Plane
Leaves and fruit of a London Plane
style="background:#Template:Taxobox colour;" | Scientific classification
Kingdom: Plantae
(unranked) Eudicots
Order: Proteales
Family: Platanaceae
Genus: Platanus
Species

See text

WikiDoc Resources for Platanus

Articles

Most recent articles on Platanus

Most cited articles on Platanus

Review articles on Platanus

Articles on Platanus in N Eng J Med, Lancet, BMJ

Media

Powerpoint slides on Platanus

Images of Platanus

Photos of Platanus

Podcasts & MP3s on Platanus

Videos on Platanus

Evidence Based Medicine

Cochrane Collaboration on Platanus

Bandolier on Platanus

TRIP on Platanus

Clinical Trials

Ongoing Trials on Platanus at Clinical Trials.gov

Trial results on Platanus

Clinical Trials on Platanus at Google

Guidelines / Policies / Govt

US National Guidelines Clearinghouse on Platanus

NICE Guidance on Platanus

NHS PRODIGY Guidance

FDA on Platanus

CDC on Platanus

Books

Books on Platanus

News

Platanus in the news

Be alerted to news on Platanus

News trends on Platanus

Commentary

Blogs on Platanus

Definitions

Definitions of Platanus

Patient Resources / Community

Patient resources on Platanus

Discussion groups on Platanus

Patient Handouts on Platanus

Directions to Hospitals Treating Platanus

Risk calculators and risk factors for Platanus

Healthcare Provider Resources

Symptoms of Platanus

Causes & Risk Factors for Platanus

Diagnostic studies for Platanus

Treatment of Platanus

Continuing Medical Education (CME)

CME Programs on Platanus

International

Platanus en Espanol

Platanus en Francais

Business

Platanus in the Marketplace

Patents on Platanus

Experimental / Informatics

List of terms related to Platanus

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Platanus (/[invalid input: 'icon']ˈplætənəs/)Template:Sfn is a genus comprising a small number of tree species native to the Northern Hemisphere. They are the sole living members of the family Platanaceae.

All members of Platanus are tall, reaching 30 to 50 meters in height. All except for P. kerrii are deciduous, and most are found in riparian or other wetland habitats in the wild, though proving drought-tolerant in cultivation. The hybrid London Plane has proved particularly tolerant of urban conditions.

They are often known in English as planes or plane trees. Some North American species are called sycamores (especially Platanus occidentalisTemplate:Sfn), although that term also refers to either the fig Ficus sycomorus, the plant originally so named, or the Great, or Sycamore Maple, Acer pseudoplatanus.Template:Sfn

Botany

File:Platane, Trsteno.JPG
Bole of an aged Platanus, in Trsteno, near Dubrovnik, Croatia

The flowers are reduced and are borne in balls (globose heads); 3–7 hairy sepals may be fused at the base, and the petals are 3–7 and are spatulate. Male and female flowers are separate, but borne on the same plant (monoecious). The number of heads in one cluster (inflorescence) is indicative of the species (see table below). The male flower has 3–8 stamens; the female has a superior ovary with 3–7 carpels. Plane trees are wind-pollinated. Male flower-heads fall off after shedding their pollen.

After being pollinated, the female flowers become achenes that form an aggregate ball. Typically, the core of the ball is 1 cm in diameter and is covered with a net of mesh 1 mm, which can be peeled off. The ball is 2.5–4 cm in diameter and contains several hundred achenes, each of which has a single seed and is conical, with the point attached downward to the net at the surface of the ball. There is also a tuft of many thin stiff yellow-green bristle fibers attached to the base of each achene. These bristles help in wind dispersion of the fruits as in the dandelion.

The leaves are simple. In the subgenus Platanus they have a palmate outline. The base of the leaf stalk (petiole) is enlarged and completely wraps around the young stem bud in its axil. The axillary bud is exposed only after the leaf falls off.

The mature bark peels off or exfoliates easily in irregularly shaped patches, producing a mottled, scaly appearance. On old trunks, bark may not flake off, but thickens and cracks instead.

Phylogeny

File:Konak Kneza Miloša, pogled kroz platan.jpg
Platanus from 1834 in front of the Prince Miloš's Residence in Belgrade, Serbia.
File:Platanus alley.jpg
Avenue of plane trees
File:Normandie Calvados Bayeux1 tango7174.jpg
Platanus dating from 1797, Bayeux,
Normandie, France
File:France's largest plane tree , Saint-Guilhem-le-Désert.JPG
France's largest plane tree, Saint-Guilhem-le-Désert
File:Platanus.JPG
Platanus trees in South America.

There are two subgenera, subgenus Castaneophyllum containing the anomalous P. kerrii, and subgenus Platanus, with all the others; recent studies in MexicoTemplate:Sfn have increased the number of accepted species in this subgenus. Within subgenus Platanus, genetic evidence suggests that P. racemosa is more closely related to P. orientalis than it is to the other North American species.Template:Sfn There are fossil records of plane trees as early as 115 million years (the Lower Cretaceous). Despite the geographic separation between North America and Old World, species from these continents will cross readily resulting in fertile hybrids such as the London Plane.

Species

The following are recognized species of plane trees:

Botanic name Common names Distribution Flowerheads Notes
Platanus × acerifolia
(P. occidentalis × P. orientalis;
syn. P. × hispanica, P. × hybrida)
London Plane, Hybrid Plane Cultivated origin 1–6 Subgenus Platanus
Platanus chiapensis Chiapas Plane southeast Mexico ? Subgenus Platanus
Platanus gentryi Gentry's Plane western Mexico ? Subgenus Platanus
Platanus kerrii Kerr's Plane Laos, Vietnam 10–12 Subgenus Castaneophyllum
Platanus mexicana Mexican Plane northeast and central Mexico 2–4 Subgenus Platanus
Platanus oaxacana Oaxaca Plane southern Mexico ? Subgenus Platanus
Platanus occidentalis American Sycamore, American Plane, Buttonwood, Occidental Plane eastern North America 1–2 Subgenus Platanus
Platanus orientalis Oriental Plane southeast Europe, southwest Asia 3–6 Subgenus Platanus
Platanus racemosa California Sycamore, Western Sycamore, Aliso California 3–7 Subgenus Platanus
Platanus rzedowskii Rzedowski's Plane eastern Mexico ? Subgenus Platanus
Platanus wrightii Arizona Sycamore Arizona, New Mexico, northwest Mexico 2–4 Subgenus Platanus

Diseases

Planes are susceptible to Plane Anthracnose (Apiognomonia veneta), a fungal disease that can defoliate the trees in some years. The worst infections are associated with cold, wet spring weather. P. occidentalis and the other American species are the most susceptible, with P. orientalis the most resistant. The hybrid London Plane is intermediate in resistance.

Ceratocystis platani, a wilt disease, has become a significant problem in recent years in much of Europe.Template:Sfn

Other diseases such as powdery mildew occur frequently, but are of lesser importance.

Platanus species are used as food plants by the larvae of some Lepidoptera species including Phyllonorycter platani and Setaceous Hebrew Character.

Uses

The principal use of these trees is as ornamental trees, especially in urban areas and by roadsides. The London plane is particularly popular for this purpose. The American plane is cultivated sometimes for timber and investigations have been made into its use as a biomass crop. The oriental plane is widely used as an ornamental and also has a number of minor medicinal uses.

Cultural history

Most significant aspects of cultural history apply to Platanus orientalis in the Old World.

Footnotes

References

Books
  • Naumann, Helmut (2007). "Die Platane von Gortyna". In Kämmerer., Thomas Richard. Studien zu Ritual und Sozialgeschichte im Alten. Berlin, de Gruyter,. pp. 207–226. Unknown parameter |trans_title= ignored (help)
  • Sunset Western Garden Book. 1995. pp. 606–607.
Journals
Web
  • "Sycamore", Merriam-Webster Online Dictionary, retrieved 2009-08-04
  • "Pathology note 7" (PDF). The Research Agency of the Forestry Commission. 2008.

External links

Template:Wikispecies

ar:دلب be:Платан be-x-old:Плятан bg:Чинар ca:Platanus cs:Platan (rod) da:Platan de:Platanen el:Πλάτανος eo:Platano fa:چنار gv:Billey plaaney ko:버즘나무과 hsb:Platana io:Platano it:Platanus he:דולב ka:ჭადარი lbe:Чинар lt:Platanas nl:Plataan oc:Platana sr:Платан fi:Plataanit sv:Platansläktet