Nepeta

Catnip
Nepeta cataria
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Asterids
Order:	Lamiales
Family:	Lamiaceae
Genus:	Nepeta
Species
See text.

Nepeta is a genus of about 250 species of flowering plants in the family Lamiaceae. The members of this group are known as catnip or catmint because of their famous effect on cats—nepeta pleasantly stimulates cats' pheromonic receptors, typically resulting in temporary euphoria. According to traditional herb medicine, catnip tends to have a sedative effect on humans.^[1]

The genus is native to Europe, Asia, and Africa. It is now also common in North America.^[2] Most of the species are herbaceous perennial plants, but some are annuals. They have sturdy stems with opposite heart-shaped, green to grayish-green leaves. The flowers are white, blue, pink or lilac and occur in several clusters toward the tip of the stems. The flowers are tubular and spotted with tiny purple dots.

Uses

Oil isolated from catnip by steam distillation is a repellent against insects, in particular mosquitoes, cockroaches and termites.^[3][4] Research suggests that in a test tube, distilled nepetalactone, the active ingredient in catnip, repels mosquitoes ten times more effectively than DEET, the active ingredient in most insect repellents,^[5][6] but that it is not as effective a repellent when used on the skin.^[7] Additionally, catnip and catnip-laced products designed for use with domesticated cats are available to consumers.

Effects on cats

Catnip and catmints are mainly known for the behavioral effects they have on cats, particularly domestics.^[8] When cats sense the bruised leaves or stems of catnip, they may roll over it, paw at it, chew it, lick it, leap about and purr, or heavily salivate. Some will growl, meow, scratch, or bite the hand holding it. Some cats will eat dried catnip. Often, eating too much can cause cats to be overtly aggressive; typically making them hiss.

A domestic cat demonstrating the effects of catnip such as rolling, pawing, and frisking

About two thirds of cats are susceptible to catnip.^[9] The phenomenon is hereditary; for example, most Australian cats do not react to it.^[10] There is some disagreement about the susceptibility of lions and tigers to catnip.^[10]

Catnip has nepetalactone, a terpene. Nepetalactone can be extracted from catnip by steam distillation.^[11] Cats detect it through their olfactory epithelium, not through their vomeronasal organ.^[12] At the olfactory epithelium, the nepetalactone binds to one or more olfactory receptors where it probably mimics a cat pheromone, such as the hypothetical feline facial pheromone or the cat urine odorant MMB.^{[citation needed]}

Other plants that also have this effect on cats include valerian (Valeriana officinalis) and plants that contain actinidine or dihydroactinidiolide (Smith, 2005).

Species

Nepeta curviflora flowers

• Nepeta cataria (Catnip, True Catnip, Catmint or Field Balm) is a 50–100 cm tall perennial herb resembling mint in appearance, with greyish-green leaves; the flowers are white, finely spotted with purple. It has been introduced to many countries, including the United States. A lemon-scented cultivar, N. cataria 'Citriodora', looks exactly like true catnip but has the scent of lemons and can be used like Lemon balm.

• Nepeta grandiflora (Giant Catmint or Caucasus Catmint) is lusher than true catnip and has dark green leaves and dark blue, almost purple flowers.

• Nepeta × faassenii (N. racemosa × N. nepetella; Faassen's Nepeta or Faassen's Catnip) is mostly grown as an ornamental plant. This hybrid is far smaller than either of above and is almost a ground cover. It has greyish-green leaves and light purple flowers.

• Some Dracocephalum, Glechoma and Calamintha species were formerly classified in Nepeta.

• Nepeta species are used as food plants by the larvae of some Lepidoptera (butterfly and moth) species including Coleophora albitarsella.

Selected species

References

Further reading

• Jacobs, Betty E.M. (1981). Growing and Using Herbs Successfully. Pownal, Vermont: Garden Way Publishing. 
• Turner, Ramona (May 29, 2007). "How does catnip work its magic on cats?". Scientific American. http://www.sciam.com/article.cfm?id=experts-how-does-catnip-work-on-cats. Retrieved February 14, 2009. 

External links

Wikimedia Commons has media related to: Nepeta

• Flora Europaea
• Flora of China
• Flora of Nepal
• Catnip Repels Mosquitoes More Effectively Than DEET - reported at the 222nd national meeting of the American Chemical Society
• What is in catnip anyway? Nepetalactone
• How does catnip work? HowStuffWorks, Inc. 1998–2005.
• Smith, L. Catnip. Penmarrie Cornish Rex. 1996–2005.^{[dead link]}
• Catnip Plants