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aphid

(Encyclopedia)aphid or plant louse, tiny, usually green, soft-bodied, pear-shaped insect injurious to vegetation. It is also called greenfly and blight. Aphids are mostly under 1⁄4 in. (6 mm) long. Some are wingl...

walnut

(Encyclopedia)CE5 Black walnut, Juglans nigra walnut, common name for some members of the Juglandaceae, a family of chiefly deciduous, resinous trees characterized by large and aromatic compound leaves. Species...

wasp

(Encyclopedia)wasp, name applied to many winged insects of the order Hymenoptera, which also includes ants and bees. Most wasps are carnivorous, feeding on insects, grubs, or spiders. They have biting mouthparts, a...

mulberry

(Encyclopedia)CE5 Red mulberry, Morus rubra mulberry, common name for the Moraceae, a family of deciduous or evergreen trees and shrubs, often climbing, mostly of pantropical distribution, and characterized by ...

pesticide

(Encyclopedia)pesticide, biological, physical, or chemical agent used to kill plants or animals that are harmful to people; in practice, the term pesticide is often applied only to chemical agents. Various pesticid...

vineyard

(Encyclopedia)vineyard, land on which cultivation of the grape—known as viticulture—takes place. As many as 40 varieties of grape, Vitis vinifera, are known. The few that grow wild are generally not used; all d...

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 ...

orchid

(Encyclopedia)CE5 Rose pogonia, Pogonia ophioglossoides, a member of the orchid family orchid, popular name for members of the Orchidaceae, a family of perennial herbs widely distributed in both hemispheres. Th...

mass extinction

(Encyclopedia)mass extinction, the extinction of a large percentage of the earth's species, opening ecological niches for other species to fill. There have been at least ten such events. The five greatest were thos...

flight

(Encyclopedia)CE5 Aircraft motions and control surfaces: Yaw, or motion to the left or right, is controlled by the rudder. Pitch, or climbing or dropping, is controlled by the elevators, which move in the same d...