1. Nepeta cataria L. (catnip, catmint)
Pl. 438 e, f;
Map 1974
Plants
perennial, with taproots or occasionally branched rootstocks. Stems 30–100 cm
long, erect or ascending, bluntly to sharply 4-angled, branched, densely
pubescent with felted or somewhat woolly, sometimes matted, short, white to
grayish-tinged hairs. Leaves opposite, mostly short- to more commonly
long-petiolate, the petioles unwinged or winged only at the very tip, with a
pungent odor when bruised or crushed. Leaf blades 2–8 cm long, ovate to
ovate-triangular, unlobed, the margins mostly coarsely toothed (sometimes
deeply so on larger leaves), truncate to shallowly cordate at the base, angled
to a bluntly or sharply pointed tip, the upper surface green and sparsely to
moderately pubescent with short, curved hairs, the undersurface usually pale,
densely pubescent with felted or somewhat woolly, sometimes somewhat matted,
short, white to grayish-tinged hairs, also with conspicuous sessile glands,
these sometimes obscured by the hairs. Inflorescences terminal, often appearing
as short, dense, headlike clusters when young, usually elongating into dense,
but often interrupted, spikelike racemes, these sometimes with short branches
(then paniculate), the flowers numerous per node, some sessile, others
short-stalked. Bracts 6–30 mm long, often absent from the upper inflorescence
nodes, extending past the flowers or not, narrowly ovate to lanceolate, sharply
pointed but not spinescent; bractlets inconspicuous, minute, mostly linear.
Calyces 5–7 mm long at flowering, zygomorphic, lacking a lateral projection,
usually slightly pouched on 1 side at the base, more or less tubular (often
slightly curved), the tube strongly 15-nerved (-ribbed), densely pubescent with
short, fine, mostly spreading hairs on the outer surface, also with relatively
dense, sessile glands, densely hairy in the mouth, the lips shorter than the
tube, loosely ascending, the upper lip 3-lobed, longer than the 2-lobed lower lip,
the lobes all similar, narrowly triangular, tapered to sharply pointed, but not
spinescent tips, becoming papery but not enlarged at fruiting. Corollas 7–12 mm
long, zygomorphic, 2-lipped, dull white to light cream-colored, the lower lip
with pink to purple spots or mottling, the outer surface densely short-hairy,
the tube funnelform, hairy in the throat, the lips shorter than to about as
long as the tube, the upper lip shorter than the lower lip, entire or shallowly
notched, slightly concave to more or less hooded, the lower lip spreading to
arched, 3-lobed with a large central lobe and 2 small lateral lobes, the
central lobe somewhat scoop-shaped, notched or more commonly with several small
teeth at the broadly rounded to truncate tip. Stamens 4, short-exserted (more
or less ascending under the upper corolla lip), the upper pair slightly longer
than the lower pair, the anthers small, the connective short, the pollen sacs
2, spreading, purple. Ovary deeply lobed, the style appearing more or less
basal from a deep apical notch. Style short-exserted, with 2 equal branches at
the tip. Fruits dry schizocarps, separating into usually 4 nutlets, these
1.3–2.0 mm long, mostly oblong-obovoid, rounded at the tip, the surface reddish
brown to dark brown, smooth or with few to several faint, longitudinal lines or
grooves, glabrous. 2n=32, 34, 36. June–September.
Introduced,
scattered, mostly in the northern and western halves of the state (native of
Asia; introduced widely, including nearly throughout the U.S. [including
Alsaka], Canada). Mesic upland forests, banks of streams, and bases of bluffs;
also fallow fields, old fields, pastures, fencerows, old homesites, railroads,
roadsides, and disturbed areas.
Nepeta
cataria has been used
medicinally in teas for its mild sedative properties. However, it is best known
for evoking the well-known catnip response in many different species of
felines, which was reviewed in detail by Tucker and Tucker (1988). This
psychosexual response (intoxication) apparently is under the control of a
single dominent gene (thus some cats are not susceptible) and does not become
active until the cat is about three months old. It is caused by nepetalactone,
a cyclopentanoid monoterpene, present in the plant’s essential oil. More
recently, nepetalactone from catnip has shown promise as an insect repellent
(C. J. Peterson et al., 2002; C. J. Peterson and Ems-Wilson, 2003),
particularly of cockroaches, mosquitos, and termites.
20. Ocimum L.
About 150
species, widespread in tropical and warm-temperate regions, most diverse in
South America and Africa.