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cultivation

(Encyclopedia)cultivation, tilling or manipulation of the soil, done primarily to eliminate weeds that compete with crops for water and nutrients. Cultivation may be used in crusted soils to increase soil aeration ...

broom rape

(Encyclopedia)broom rape, common name for plants of the Orobanchaceae, the broom rape family. They are parasitic on the roots of other plants; they have small leaves and little or no green color. In some species th...

lignin

(Encyclopedia)lignin lĭgˈnĭn [key], a highly polymerized and complex chemical compound especially common in woody plants. The cellulose walls of the wood become impregnated with lignin, a process called lignific...

coleus

(Encyclopedia)coleus kōˈlēəs [key], common name for a genus of plants with large colorful leaves native to tropical Asia and Africa. Several species are grown as ornamentals. Plants of the genus Coleus are in t...

Nuttall, George Henry Falkiner

(Encyclopedia)Nuttall, George Henry Falkiner nŭtˈôl [key], 1862–1937, American-British bacteriologist, b. San Francisco, M.D. Univ. of California, 1884, Ph.D. Univ. of Göttingen, 1890. In 1899 he became assoc...

Hench, Philip Showalter

(Encyclopedia)Hench, Philip Showalter, 1896–1965, American physician, b. Pittsburgh, M.D. Univ. of Pittsburgh, 1920. Associated with the Mayo Foundation of the Univ. of Minnesota school of medicine after 1921, he...

pitcher plant

(Encyclopedia)pitcher plant, any of several insectivorous plants with leaves adapted for trapping insects. Each leaf forms a “pitcher,” a somewhat trumpet-shaped enclosure, usually containing a liquid. An insec...

climbing plant

(Encyclopedia)climbing plant, any plant that in growing to its full height requires some support. Climbing plants may clamber over a support (climbing rose), twine up a slender support (hop, honeysuckle), or grasp ...

trench mouth

(Encyclopedia)trench mouth, common term for Vincent's infection, an ulcerative membranous infection of the gums and mouth, by noncontagious infection, associated with a fusiform bacillus and a spirochete. Poor oral...

Jacobi, Abraham

(Encyclopedia)Jacobi, Abraham jəkōˈbē [key], 1830–1919, American pediatrician, founder of pediatrics in the United States, b. Westphalia, Germany, M.D. Bonn, 1851. He was imprisoned for participating in the R...