Sempervivum tectorum

Common Houseleek
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Core eudicots
Order:	Saxifragales
Family:	Crassulaceae
Genus:	Sempervivum
Species:	S. tectorum
Binomial name
Sempervivum tectorum L.

Sempervivum tectorum is a succulent evergreen perennial whose many common names include Common houseleek,^[1] Jove's beard, Jupiter's eye, Thor's beard, St. George's Beard,^[2] and Welcome-home-husband-though-never-so-drunk^[3]—it sometimes shares the last of these names with Sedum acre.^[4] It may also be called, generically, sedum or stonecrop.^[2] Another name it shares with a variety of related species is hen and chicks.^[5]

It is used as an ornamental plant. The succulent evergreen leaves form a basal rosette; they can be green, red, purple or yellow. The flowers, which appear on branched stalks, can be purple, red or pink depending on the cultivar.

Description

Sempervivum tectorum was described in 1753 by Linnaeus, who noted that its leaves are fleshy, evergreen, and cilate, that is, fringed with hairs.^[6]

Flora of North America describes S. tectorum as a perennial herb with a basal rosette of succulent sessile leaves 4–10 cm in diameter. Flowers occur in multiples of 8–16 on erect flat-topped stalks.^[6][7][8] They note, however, that the species is "highly variable," in part because "hundreds of cultivars have been propagated, sold, and traded for nearly 200 years."^[8]

Folklore and herbalism

The plant has been traditionally thought to protect against thunderstorms, and grown on house roofs for that reason,^[9] which is why it is called House Leek.^[2] Many of its popular names in different languages reflect an association with the Roman thunder-god Jupiter, notably the Latin barba Jovis (Jupiter's beard), referred to in the Floridus traditionally attributed to Aemilius Macer,^[10] and its French derivative joubarbe, which has in turn given rise to jubard and jo-barb in English; or with the Norse thunder-god Thor as in German Donnerbart.^[11] It is also called simply thunder-plant.^[12] Anglo-Saxon þunorwyrt^[13][14] may have either meaning. However, the association with Jupiter has also been derived from a resemblance between the flowers and the god's beard; in modern times, it has also been called St. George's beard.^[2]

Other common names, such as Anglo-Saxon singrēne, Modern English sigrim, sil-green, etc. and aye-green,^[12][15] refer to its longevity. William Fernie tells a tale in support of this:

History relates that a botanist tried hard for eighteen months to dry a plant of the House Leek for his herbarium, but failed in this object. He afterwards restored it to its first site when it grew again as if nothing had interfered with its ordinary life.^[2]

It has been believed to protect more generally against decay and against witchcraft.^[2] Jacob Grimm quotes a Provencal troubadour: "e daquel erba tenon pro li vilan sobra lur maiso" — "and that plant they keep against evil atop their house."^[16] In his Capitulare de villis vel curtis imperii, Charlemagne recommended it be grown on top of houses.^[17] In some places, S. tectorum is still traditionally grown on the roofs of houses.^[18][19]

The juice has been used in herbal medicine as an astringent and treatment for skin and eye diseases, including by Galen and Dioscorides, to ease inflammation and, mixed with honey, to treat thrush; however, large doses have an emetic effect.^[20] Pliny also mentions it, and Marcellus Empiricus listed it as a component in external treatments for contusions, nervous disorders, intestinal problems and abdominal pain, and mixed with honey, as part of the antidotum Hadriani (Hadrian's antidote), a broad-spectrum palliative for internal complaints.^[21]

Romans grew the plant in containers in front of windows and associated it with love medicine.^[2]

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  Sempervivum Tectorum "Greenii", Huntington Desert Garden

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  Sempervivum tectorum

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  Sempervivum tectorum boutignyanum in flower

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  Rosette with drops of dew

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  Illustration from Otto Wilhelm Thomé, Flora von Deutschland, Österreich und der Schweiz, 1885

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  Sempervivum tectorum with flowers in Uppsala Botaniska Trädgården

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  Flower of cultivated variety, photographed in Spain

References

1. ^ "Sempervivum tectorum L. common houseleek". USDA. http://plants.usda.gov/java/profile?symbol=SETE5. Retrieved 7 July 2011. 
2. ^ ^{a b c d e f g} William Thomas Fernie, Herbal Simples Approved for Modern Uses of Cure, 3rd enlarged ed. Bristol: Wright, 1914, repr. Teddington: Echo Library, 2008, ISBN 978-1-40687-552-2, p. 189.
3. ^ Watts, Donald (2007). Dictionary of Plant Lore. Elsevier. pp. 202. ISBN 9780123740861. http://books.google.com/books?id=WAagnZNb0cAC. 
4. ^ Fenton, James. "Clare Was Right". NY Review of Books. http://www.nybooks.com/articles/archives/2005/jun/23/clare-was-right/. Retrieved 7 July 2011. 
5. ^ David Beaulieu. "Hens and Chicks". http://landscaping.about.com/od/plantsforsunnydryareas/p/hens_and_chicks.htm. 
6. ^ ^{a b} Linnæus, Carl von (1753), "Sempervivum", Species plantarum, 1, Holmiae, p. 464, http://www.botanicus.org/page/358483, retrieved 6 July 2011 
7. ^ Gen. Pl (5 ed.), 1754, p. 209, http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=130076, retrieved 6 July 2011 
8. ^ ^{a b} Linnaeus (1753). "Species Plantarum". Flora of North America. p. 464. http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=220012387. Retrieved 6 July 2011. 
9. ^ Cockayne, Oswald (1866), "Hamƿyɼꞇ", Leechdoms, Wortcunning, and Starcraft of Early England: Being a Collection of Documents, for the most part never before printed, illustrating the History of Science in this Country Before the Norman Conquest, Rerum Britannicarum Medii Aevi Scriptores or Chronicles and Memorials of Great Britain and Ireland During the Middle Ages [The Rolls Series], 3, London: Longman, p. 329 .
10. ^ In Fernie, p. 189, "Quem sempervivam dicunt quoniam viret omni Tempore—'Barba Jovis' vulgari more vocatur" – "Which they call semperviva because it will live for all time—'beard of Jove' it is called by vulgar custom"" .
11. ^ Grimm, Jacob (1882), Teutonic Mythology, 1, tr. James Steven Stallybrass, London: Bell, p. 183, http://books.google.com/books?id=neQtAAAAIAAJ&pg=PA183&dq=Grimm+Donnerbart&hl=en&ei=qYASTuKJGZCasAO81eSsDg&sa=X&oi=book_result&ct=result&resnum=1&ved=0CCkQ6AEwAA#v=onepage&q&f=false ; however, Grimm (1883), Teutonic Mythology, 4, p. 1672, http://books.google.com/books?id=xMAoAAAAYAAJ&pg=PA1672&dq=Grimm+Donner-bart&hl=en&ei=yLgTTvnfD-bWiALMzuXKDQ&sa=X&oi=book_result&ct=result&resnum=1&ved=0CCkQ6AEwAA#v=onepage&q=donner-bart&f=false  states that Donner-bart is sedum telephium.
12. ^ ^{a b} Britten, James; Holland, Robert (1878), A Dictionary of English Plant-Names, English Dialect Society, London: Trübner, p. 610 and individual listings, http://books.google.com/books?id=nVUJAAAAQAAJ&pg=PA271&dq=Cockayne+sempervivum&hl=en&ei=95kSTq3DO4y6sAOe1s2iDg&sa=X&oi=book_result&ct=result&resnum=3&ved=0CEIQ6AEwAg#v=onepage&q=sempervivum%20tectorum&f=false .
13. ^ Grimm (1883), Teutonic Mythology, 4, p. 1346, http://books.google.com/books?id=xMAoAAAAYAAJ&pg=PA1672&dq=Grimm+Donner-bart&hl=en&ei=yLgTTvnfD-bWiALMzuXKDQ&sa=X&oi=book_result&ct=result&resnum=1&ved=0CCkQ6AEwAA#v=onepage&q=house-leek%20planted%20on%20cottage%20roofs&f=false .
14. ^ Toller, T. Northcote, ed. (1973) [1898], "þunor-wyrt", An Anglo-Saxon Dictionary: Based on the Manuscript Collection of the late Joseph Bosworth, Oxford: Oxford University, http://bosworth.ff.cuni.cz/032243 , glossing it as "Thunder-plant".
15. ^ Cockayne, p. 344 , glosses sinȝrene simply as "sedum"; Bosworth-Toller, "sin-gréne", http://bosworth.ff.cuni.cz/finder/3/singrene , as sempervivum tectorum but notes it is also used of other plants.
16. ^ Grimm, volume 1, p. 183, footnote 3.
17. ^ (in Latin) The Capitulare de Villis, Carolingian Polyptiques, University of Leicester, January 2008, http://www.le.ac.uk/hi/polyptyques/capitulare/latin.html, retrieved 5 July 2011, "Et ille hortulanus habeat super domum suam Iovis barbam"  — English, http://www.le.ac.uk/hi/polyptyques/capitulare/trans.html#70, "And the gardener shall have house-leeks growing on his house." ; however, "Barba Iovis", in August Friedrich von Pauly and Georg Wissowa, Paulys Real-Encyclopädie der classischen Altertumswissenschaft, volume 2, rev. ed. Stuttgart: Metzler, 1896, p. 2818 (German) says he recommended including it in the garden as a domestic remedy.
18. ^ "The Sempervivum Page Linnaeus (1757)". Richard J. Hodgkiss. http://www.succulent-plant.com/families/crassulaceae/sempervivum.html. Retrieved 7 July 2011. 
19. ^ "Pale Green Sempervivum tectorum Hen & Chicks". Paghat. http://www.paghat.com/semptectorum.html. Retrieved 7 July 2011. "In Slavic nations, the tradition of roof-top houseleeks is still practiced." 
20. ^ Fernie, pp. 189–90.
21. ^ Pauly-Wissowa.