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defoliant

(Encyclopedia)defoliant, any one of several chemical compounds that, when applied to plants, can alter their metabolism, causing the leaves to drop off. In agriculture defoliants are used to eliminate the leaves of...

corn borer

(Encyclopedia)corn borer or European corn borer, common name for the larva of a moth of the family Pyralidae, introduced from S Europe into the Boston area in 1917. The corn borer, Ostrinia nubilalis, has steadily ...

eukaryote

(Encyclopedia)eukaryote yo͞okârˈē-ōtˌ [key], a cell or organism composed of cells that have a membrane-bound nucleus and organelles (mitochondria, chloroplasts; see cell, in biology) and genetic material orga...

eutrophication

(Encyclopedia)eutrophication yo͞otrōˌfĭkāˈshən [key], aging of a lake by biological enrichment of its water. In a young lake the water is cold and clear, supporting little life. With time, streams draining i...

peyote

(Encyclopedia)peyote pāōˈtē [key], spineless cactus (Lophophora williamsii), ingested by indigenous people in Mexico and the United States to produce visions. The plant is native to the SW United States, partic...

Mendel, Gregor Johann

(Encyclopedia)Mendel, Gregor Johann grāˈgôr yōˈhän mĕnˈdəl [key], 1822–84, Austrian monk noted for his experimental work on heredity. He entered the Augustinian monastery in Brno in 1843, taught at a loc...

cactus

(Encyclopedia)cactus, any plant of the family Cactaceae, a large group of succulents found almost entirely in the New World. A cactus plant is conspicuous for its fleshy green stem, which performs the functions of ...

La Verne

(Encyclopedia)La Verne lə vûrn [key], city (1990 pop. 30,897), Los Angeles co., S Calif., a suburb of Los Angeles; inc. 1906. La Verne, which began as a citrus-processing center, now has varied manufacturing, inc...

menthol

(Encyclopedia)menthol, white crystalline substance with a characteristic pungent odor. It is derived from the oil of the peppermint plant, Mentha piperita (see mint), or prepared synthetically from coal tar. An alc...

mare's-tail

(Encyclopedia)mare's-tail, any plant of the genus Hippuris, perennial, submerged aquatic herbs of temperate and frigid regions. Mare's-tails have an erect stem bearing whorls of small leaves, so they resemble some ...