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Burbank, Luther

(Encyclopedia)Burbank, Luther bûrˈbănk [key], 1849–1926, American plant breeder, b. Lancaster, Mass. He experimented with thousands of plant varieties and developed many new ones, including new varieties of pr...

Three Mile Island

(Encyclopedia)Three Mile Island, site of a nuclear power plant 10 mi (16 km) south of Harrisburg, Pa. On Mar. 28, 1979, failure of the cooling system of the No. 2 nuclear reactor led to overheating and partial melt...

bittersweet

(Encyclopedia)bittersweet, name for two unrelated plants, belonging to different families, both fall-fruiting woody vines sometimes cultivated for their decorative scarlet berries. One, called also woody nightshade...

cycad

(Encyclopedia)cycad sīˈkăd [key], any plant of the order Cycadales, tropical and subtropical palmlike evergreens. The cycads, ginkgoes, and conifers comprise the three major orders of gymnosperms, or cone-bearin...

grafting

(Encyclopedia)CE5 Two methods of grafting grafting, horticultural practice of uniting parts of two plants so that they grow as one. The scion, or cion, the part grafted onto the stock or rooted part, may be a s...

fungicide

(Encyclopedia)fungicide fŭnˈjəsīdˌ, fŭngˈgə– [key], any substance used to destroy fungi. Some fungi are extremely damaging to crops (see diseases of plants), and others cause diseases in humans and other ...

nitrogen cycle

(Encyclopedia)CE5 Nitrogen cycle nitrogen cycle, the continuous flow of nitrogen through the biosphere by the processes of nitrogen fixation, ammonification (decay), nitrification, and denitrification. Nitrogen...

soil

(Encyclopedia)soil, surface layer of the earth, composed of fine rock material disintegrated by geological processes; and humus, the organic remains of decomposed vegetation. In agriculture, soil is the medium that...

loganberry

(Encyclopedia)loganberry, blackberrylike plant of the genus Rubus of the family Rosaceae (rose family). See bramble. ...

Parker Dam

(Encyclopedia)Parker Dam, at the Ariz.–Calif. line, on the Colorado River; completed 1938. It is 320 ft (98 m) high and 856 ft (261 m) long. The dam impounds water for Los Angeles and other coastal cities, has a ...