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Catnip oil is obtained from Nepeta cataria L. The genus Nepeta comprises annual or perennial herbs or shrubs which are mainly distributed in temperate Eurasia and North Africa. Although no members of this genus are native to North America, a few can be found as garden escapes. The three species of Nepeta that have been found in North America are Nepeta cataria L. (including var. citriodora Beck), N. grandiflora Bieb. and N. racemosa La. (syn. N. mussini Spreng.).
Nepeta cataria L., or catnip as it is more commonly known, is an herbaceous perennial plant which is native to Europe and Asia. Nevertheless, catnip is completely naturalized in North America where it can be found commonly occurring as a weed in waste land and along roadsides. In Canada, it ranges from British Columbia to Nova Scotia while in the United States it can be found southwards from Canada to Oregon, Georgia, Kansas and Utah (Gill, 1971), although it is found in abundance in the vicinity of the Great Lakes.
A number of years ago, McElvain et al. (1941/1942) examined the essential oil of catnip and identified nepetalactone and a number of its degradation products.