Ilex aquifolium
{{short description|Species of flowering plant in the family Aquifoliaceae}}
{{redirect|Common holly|the Canadian musician|Common Holly}}
{{speciesbox
|image = Ilex-aquifolium (Europaeische Stechpalme-1).jpg
| image_caption = Leaves and fruit
| status = LC
| status_system = IUCN3.1
|genus = Ilex
|species = aquifolium
|authority = Linnaeus
|range_map = Ilex aquifolium range.svg
|range_map_caption = Distribution map of Ilex aquifolium
}}
File:Ilex aquifolium in the Tashkent Botanical Garden.jpg
Ilex aquifolium, the holly, common holly, English holly, European holly, or occasionally Christmas holly, is a species of flowering plant in the family Aquifoliaceae, native to western and southern Europe, northwest Africa, and southwest Asia.Flora Europaea: [http://rbg-web2.rbge.org.uk/cgi-bin/nph-readbtree.pl/feout?FAMILY_XREF=&GENUS_XREF=Ilex&SPECIES_XREF=aquifolium&TAXON_NAME_XREF=&RANK= Ilex aquifolium]Med-Checklist: [http://ww2.bgbm.org/mcl/PTaxonDetail.asp?NameId=1263&PTRefFK=1273 Ilex aquifolium]Rushforth, K. (1999). Trees of Britain and Europe. Collins {{ISBN|0-00-220013-9}}.Flora of NW Europe: [http://ip30.eti.uva.nl/BIS/flora.php?selected=beschrijving&menuentry=soorten&id=3088 Ilex aquifolium] {{webarchive|url=https://web.archive.org/web/20090609025123/http://ip30.eti.uva.nl/BIS/flora.php?selected=beschrijving&menuentry=soorten&id=3088 |date=2009-06-09 }} It is regarded as the type species of the genus Ilex, which by association is also called "holly". It is an evergreen tree or shrub found, for example, in shady areas of forests of oak and in beech hedges. In the British Isles it is one of very few native hardwood evergreen trees. It has a great capacity to adapt to different conditions and is a pioneer species that repopulates the margins of forests or clearcuts.
I. aquifolium can exceed 10 m in height, but is often found at much smaller heights, typically {{convert|2-3 |m|ft|abbr=on}} tall and broad, with a straight trunk and pyramidal crown, branching from the base. It grows slowly and does not usually fully mature due to cutting or fire. It can live 500 years, but usually does not reach 100.
Ilex aquifolium is the species of holly long associated with Christmas, and previously the Roman festival of Saturnalia. Its glossy green prickly leaves and bright red berries (produced only by the female plant) are represented in wreaths, garlands and cards wherever Christmas is celebrated. It is a subject of music and folklore, especially in the British tradition. It is also a popular ornamental shrub or hedge, with numerous cultivars in a range of colours.
Description
File:Ilex aquifolium berries rime.jpg
Ilex aquifolium grows to {{convert|10-25 |m|ft|abbr=on}} tall with a woody stem as wide as {{convert|40-80 |cm|in|abbr=on}}, rarely {{convert|100 |cm|in|abbr=on}} or more, in diameter. The leaves are 5–12 cm long and 2–6 cm broad; they are evergreen, lasting about five years, and are dark green on the upper surface and lighter on the underside, oval, leathery, shiny, and about 5 to 9 cm long. In the young and in the lower limbs of mature trees, the leaves have three to five sharp spines on each side, pointing alternately upward and downward, while leaves of the upper branches in mature trees lack spines.
The flowers are white, four-lobed, and pollinated by bees. Holly is dioecious, meaning that there are male plants and female plants. The sex cannot be determined until the plants begin flowering, usually between 4 and 12 years of age. In male specimens, the flowers are yellowish and appear in axillary groups. In the female, flowers are isolated or in groups of three and are small and white or slightly pink, and consist of four petals and four sepals partially fused at the base.
The fruit only appears on female plants, which require male plants nearby to fertilise them. The fruit is a drupe (stone fruit), about 6–10 mm in diameter, a bright red or bright yellow, which matures around October or November; at this time they are very bitter due to the ilicin content{{cite book | first=Heinz, A. |last=Hoppe |date=1975 |title=Drogenkunde |publisher=W. de Gruyter |isbn=3-13-566001-X }} and so are rarely eaten until late winter after frost has made them softer and more palatable. They are eaten by rodents, birds and larger herbivores. Each fruit contains 3 to 4 seeds which do not germinate until the second or third spring.{{cite journal|last=Peterken|first=G. F.|author2=Lloyd, P. S.|title=Ilex aquifolium L.|journal=Journal of Ecology|date=November 1967|volume=55|issue=3|pages=841–858|doi=10.2307/2258429|jstor=2258429|bibcode=1967JEcol..55..841P }}
Distribution and habitat
Today, holly is found in western Asia and Europe in the undergrowth of oak forest and beech forest in particular, although at times it can form a dense thicket as the dominant species. It requires moist, shady environments, found within forests or in shady slopes, cliffs, and mountain gorges.
Along the west coast of the United States and Canada, from California to British Columbia, non-native English Holly has proved very invasive, quickly spreading into native forest habitat, where it thrives in shade and crowds out native species. It has been placed on the Washington State Noxious Weed Control Board's monitor list, and is a Class C invasive plant in Portland.{{Cite web | url=http://www.nwcb.wa.gov/weeds/english-holly | title=Washington State Noxious Weed Control Board}}{{cite web |url=http://bcinvasives.ca/invasive-species/identify/invasive-species/invasive-plants/english-holly/ |title=English Holly | Invasive Species Council of British Columbia | ISCBC Plants & Animals |access-date=2015-08-14 |url-status=dead |archive-url=https://web.archive.org/web/20150906192403/http://bcinvasives.ca/invasive-species/identify/invasive-species/invasive-plants/english-holly/ |archive-date=2015-09-06 }}{{cite web| url=http://www.cal-ipc.org/ip/management/plant_profiles/Ilex_aquifolium.php| title=Ilex aquifolium (English holly)| publisher=California Invasive Plant Council| access-date=2016-10-02| url-status=dead| archive-url=https://web.archive.org/web/20160816033833/http://www.cal-ipc.org/ip/management/plant_profiles/Ilex_aquifolium.php| archive-date=2016-08-16}}
During the Cenozoic Era, the Mediterranean region, Europe, and northwest Africa had a wetter climate and were largely covered by laurel forests. Holly was a typical representative species of this biome, where many current species of the genus Ilex were present. With the drying of the Mediterranean Basin during the Pliocene, the laurel forests gradually retreated, replaced by more drought-tolerant sclerophyll plant communities. The modern Ilex aquifolium resulted from this change.{{clarify|reason=does this refer to the modern distribution or the modern species?|date=February 2017}}{{citation needed|date=February 2017}} Most of the last remaining laurel forests around the Mediterranean are believed to have died out approximately 10,000 years ago at the end of the Pleistocene.
Ecology
File:Holly thicket, Holly Hurst, Sutton Park - geograph.org.uk - 1859863.jpg in the West midlands, England.]]
Holly is a rugged pioneer species that prefers relatively moist areas, and tolerates frost as well as summer drought. The plant is common in the garrigue and maquis and is also found in deciduous forest and oak forest.
Pure stands of hollies can grow into a labyrinth of vaults in which thrushes and deer take refuge, while smaller birds are protected among their spiny leaves. After the first frost of the season, holly fruits become soft and fall to the ground serving as important food in its native regions for winter birds at a time of scarce resources.
The flowers are attractive as nectar sources for insects such as bees, wasps, flies, and small butterflies. The commonly-encountered pale patches on leaves are due to the leaf-mine insect Phytomyza ilicis.
It is an invasive species on the West Coast of Canada and the United States as well as in Hawaii.{{cite web| url=http://www.kingcounty.gov/environment/animalsAndPlants/noxious-weeds/weed-identification/english-holly.aspx| title=English Holly - Ilex aquifolium| publisher=King County, Washington| access-date=2011-01-30| archive-date=2011-02-27| archive-url=https://web.archive.org/web/20110227202332/http://www.kingcounty.gov/environment/animalsAndPlants/noxious-weeds/weed-identification/english-holly.aspx| url-status=dead}}
Epigenetics
Holly is well known in epigenetics. Some cultivars have smooth leaf edges, or both smooth and prickly leaf edges on the same plant. In response to stress these cultivars can produce leaves with more prickles.{{cite web | url=https://www.phipps.conservatory.org/blog/detail/biopgh-blog-to-prickle-or-not-to-prickle-holly-leaves-and-epigenetics | title=#bioPGH blog – to Prickle or Not to Prickle: Holly Leaves and Epigenetics | Phipps Conservatory and Botanical Gardens | Pittsburgh PA }}
Cultivation
Ilex aquifolium is widely grown in parks and gardens in temperate regions.{{cite book|title=RHS A-Z encyclopedia of garden plants|year=2008|publisher=Dorling Kindersley|location=United Kingdom|isbn=978-1405332965|page=1136}} Hollies are often used for hedges; the spiny leaves make them difficult to penetrate, and they take well to pruning and shaping.Northumbria Police: [http://ww2.northumbria.police.uk/ePolicing/Web/WMS.nsf/CrimeReductionContentDocs/CRD000301 Security starts at the Garden Gate] {{Webarchive|url=http://webarchive.nationalarchives.gov.uk/20081108035234/http://ww2.northumbria.police.uk/ePolicing/Web/WMS.nsf/CrimeReductionContentDocs/CRD000301 |date=2008-11-08 }}
=AGM cultivars=
Numerous cultivars have been selected,Huxley, A., ed. (1992). New RHS Dictionary of Gardening. Macmillan {{ISBN|0-333-47494-5}}. of which the following have gained the Royal Horticultural Society's Award of Garden Merit:{{cite web | url= https://www.rhs.org.uk/plants/pdfs/agm-lists/agm-ornamentals.pdf | title = AGM Plants - Ornamental | date = July 2017 | page = 43 | publisher = Royal Horticultural Society | access-date = 3 March 2018}}
{{div col|colwidth=15em}}
- I. aquifolium{{cite web|url=https://www.rhs.org.uk/Plants/9087/Ilex-aquifolium/Details |title=RHS Plant Selector Ilex aquifolium AGM / RHS Gardening |publisher=Apps.rhs.org.uk |access-date=2020-07-04}}
- 'Amber' (female){{cite web|url=https://www.rhs.org.uk/Plants/97772/Ilex-aquifolium-Amber-(f)/Details |title=RHS Plant Selector Ilex aquifolium 'Amber' (f) AGM / RHS Gardening |publisher=Apps.rhs.org.uk |access-date=2020-07-04}}
- 'Argentea Marginata'{{cite web|url=https://www.rhs.org.uk/Plants/91514/Ilex-aquifolium-Argentea-Marginata-(f-v)/Details |title=RHS Plant Selector Ilex aquifolium 'Argentea Marginata' (f/v) AGM / RHS Gardening |publisher=Apps.rhs.org.uk |access-date=2020-07-04}}
- 'Ferox Argentea'{{cite web|url= https://www.rhs.org.uk/Plants/97146/Ilex-aquifolium-Ferox-Argentea-(m-v)/Details |title=RHS Plant Selector Ilex aquifolium 'Ferox Argentea' (m/v) AGM / RHS Gardening |publisher=Apps.rhs.org.uk |access-date=2020-09-10}}
- 'Golden Queen'{{cite web|url= https://www.rhs.org.uk/Plants/93164/Ilex-aquifolium-Golden-Queen-(m-v)/Details |title=RHS Plant Selector Ilex aquifolium 'Golden Queen' (m/v) AGM / RHS Gardening |publisher=Apps.rhs.org.uk |access-date= 2020-09-16}}
- 'Handsworth New Silver'{{cite web|url= https://www.rhs.org.uk/Plants/89248/Ilex-aquifolium-Handsworth-New-Silver-(f-v)/Details |title=RHS Plant Selector Ilex aquifolium 'Handsworth New Silver' (f/v) AGM / RHS Gardening |publisher=Apps.rhs.org.uk |access-date=2020-09-16}}
- 'J.C. van Tol'{{cite web|url= https://www.rhs.org.uk/Plants/75559/Ilex-aquifolium-J-C-van-Tol-(f)/Details |title=RHS Plant Selector Ilex aquifolium 'J.C. van Tol' (f) AGM / RHS Gardening |publisher=Apps.rhs.org.uk |access-date=2020-09-16}}
- 'Madame Briot'{{cite web|url= https://www.rhs.org.uk/Plants/96613/Ilex-aquifolium-Madame-Briot-(f-v)/Details |title=RHS Plant Selector Ilex aquifolium 'Madame Briot' (f/v) AGM / RHS Gardening |publisher=Apps.rhs.org.uk |access-date=2020-09-16}}
- 'Pyramidalis'{{cite web|url= https://www.rhs.org.uk/Plants/95739/Ilex-aquifolium-Pyramidalis-(f)/Details |title=RHS Plant Selector Ilex aquifolium 'Pyramidalis' (f) AGM / RHS Gardening |publisher=Apps.rhs.org.uk |access-date=2020-09-16}}
- 'Silver Queen'{{cite web|url= https://www.rhs.org.uk/Plants/89342/Ilex-aquifolium-Silver-Queen-(m-v)/Details |title=RHS Plant Selector Ilex aquifolium 'Silver Queen' (m/v) AGM / RHS Gardening |publisher=Apps.rhs.org.uk |access-date=2020-09-16}}
{{div col end}}
=''Ilex'' × ''altaclerensis''=
The hybrid Ilex × altaclerensis was developed at Highclere Castle in Hampshire, England, in 1835, a cross between I. aquifolium and the tender species I. perado. The following cultivars have gained the RHS AGM:
{{div col|colwidth=30em}}
- 'Belgica Aurea'{{cite web|url= https://www.rhs.org.uk/Plants/96268/Ilex-x-altaclerensis-Belgica-Aurea-(f-v)/Details |title=RHS Plant Selector Ilex × altaclerensis 'Belgica Aurea' (f/v) AGM / RHS Gardening |publisher=Apps.rhs.org.uk |access-date=2020-09-16}}
- 'Camelliifolia'{{cite web|url= https://www.rhs.org.uk/Plants/99033/Ilex-x-altaclerensis-Camelliifolia-(f)/Details |title=RHS Plant Selector Ilex × altaclerensis 'Camelliifolia' (f) AGM / RHS Gardening |publisher=Apps.rhs.org.uk |access-date=2020-09-16}}
- 'Golden King'{{cite web|url= https://www.rhs.org.uk/Plants/95564/Ilex-x-altaclerensis-Golden-King-(f-v)/Details |title=RHS Plant Selector Ilex × altaclerensis 'Golden King' (f/v) AGM / RHS Gardening |publisher=Apps.rhs.org.uk |access-date=2020-09-16}}
- 'Lawsoniana'{{cite web|url= https://www.rhs.org.uk/Plants/94113/Ilex-x-altaclerensis-Lawsoniana-(f-v)/Details |title=RHS Plant Selector Ilex × altaclerensis 'Lawsoniana' (f/v) AGM / RHS Gardening |publisher=Apps.rhs.org.uk |access-date=2020-09-16}}
{{div col end}}
Chemistry and toxicity
Holly berries contain alkaloids, theobromine, saponins, caffeic acid, and a yellow pigment, ilixanthin.{{cite book
|last = Leikin
|first = Jerrold Blair
|author2=Frank P. Paloucek
|title = Poisoning & Toxicology Handbook, Third Edition
|publisher = Lexi-Comp Inc.
|location = Hudson, Ohio USA
|year = 2002
|page = 80
|isbn = 978-1-930598-77-5
|url = https://books.google.com/books?id=iXVqAAAAMAAJ
}}
{{cite book
|last = Turner
|first = Nancy J.
|author2=P. von Aderkas
|title = The North American Guide to Common Poisonous Plants and Mushrooms
|publisher = Timberpress
|year = 2009
|page = 210
|isbn = 978-0-88192-929-4
|url = https://books.google.com/books?id=bmGY5APFfFQC&pg=RA1-PA210
}}
The berries are generally regarded as toxic to humans.
Uses
Between the thirteenth and eighteenth centuries, before the introduction of turnips, Ilex aquifolium was cultivated for use as winter fodder for cattle and sheep. Less spiny varieties of holly were preferred, and in practice the leaves growing near the top of the tree have far fewer spines, making them more suitable for fodder.
Ilex aquifolium was once among the traditional woods for Great Highland bagpipes before tastes turned to imported dense tropical woods such as cocuswood, ebony, and African blackwood.
References
External links
- [http://www.euforgen.org/species/ilex-aquifolium/ Ilex aquifolium] - information, genetic conservation units and related resources. European Forest Genetic Resources Programme (EUFORGEN)
{{Taxonbar|from=Q192190}}
Category:Trees of mild maritime climate
Category:Medicinal plants of Africa
Category:Medicinal plants of Asia
Category:Medicinal plants of Europe
Category:Garden plants of Asia
Category:Garden plants of Europe