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A common name used loosely to designate the true clovers, sweet clovers, and other members of the plant family Fabaceae (Leguminosae). This article discusses true clovers (genus Trifolium), sweet clovers (genus Melilotus), and clover diseases. True…

The major alkaloid obtained from the seed capsules, corms, and bulbs of the meadow saffron (autumn crocus; Colchicum autumnale). Colchicine is a fairly abundant alkaloid in the dried corms (fleshy underground stems) [0.3–0.8%] and seeds (0.6–0.9%)…

Unharvested crops grown to improve soil quality or enhance pest management. Increasing numbers of farmers plant cover crops as a means of conserving soil, enhancing production, and reducing off-farm inputs. The sustainable agriculture movement has…

Much of coastal and southern California has a Mediterranean climate, which is characterized by cooler, wetter winters and hotter, drier summers. Only drought-resistant plant species can survive without irrigation in this type of climate. Turf…

Plants grown and harvested for food, feed, or industrial purposes. Farm crops may be roughly classified as follows: (1) food crops—the bread grains [wheat (see illustration) and rye], rice, sugar crops (sugarbeets and sugarcane), potatoes, and dry…

Plants grown for their fibrous material, which is used for many commercial purposes and for home industry. Many plants are grown as fiber crops because of their content or yield of fibrous material, which is used in the manufacture of textiles,…

An erect annual plant, Linum usitatissimum, cultivated as a source of flaxseed and fiber. The flax plant (Linum usitatissimum) [Fig. 1] is the source of two products: flaxseed for linseed oil and fiber for linen products. Plants with two distinct…

Grasses and legumes that make up grasslands and are consumed by grazing livestock. The grasslands represent an ancient renewable natural resource. They form 25% of the world's vegetation and occupy the largest area of any single plant type. They…

Any edible fruit borne on a tree. Tree fruits include temperate, subtropical, and tropical zone species. Most temperate-zone fruit trees are deciduous, that is, they lose their leaves in the autumn. They are grown principally in regions protected…

Two varieties of apples that have been genetically engineered not to turn brown when cut or bruised were cleared in February and March of 2015 for growth and sale in Canada by the Canadian Food Inspection Agency (CFIA) and Health Canada (HC) and in…

Crop plants that belong to the grass family (Poaceae or Gra­mineae), generally grown for their edible starchy seeds. Grain crops also are referred to as cereal crops and include wheat, rice, corn (maize), barley (see illustration), rye, oats,…

Members of the family Poaceae (Gramineae) cultivated as forage and grain for consumption. The grasses are the most useful of all the plants that cover the Earth. The cereal grass crops [wheat (Fig. 1), rice, corn (maize), rye, barley, oats,…

Intensively managed plants cultivated for food or for esthetic purposes. Plant agriculture is divided traditionally into the fields of agronomy (herbaceous field crops, mainly grains, forages, oilseeds, and fiber crops), forestry (forest trees and…

The use of certain insects to attack and destroy pests—predominantly other insects—is an intriguing and increasingly popular natural method of biological insect control. In particular, the ichneumon wasp is employed for this purpose to control pest…

Grasses that were once almost exclusively for pasture and meadow and now furnish ground cover for lawns, sports fields, industrial parks, and roadsides. Lawn and turf grasses have functional and esthetic purposes. The acreage of mowed turf grass…

A widely used cloth made from flax fibers. Linen is noted for its evenness of thread, fineness, and density. Its uses include garments, tablecloths, sheeting, towels, and thread.The flax plant (Linum usitatissimum) that supplies the fiber needs a…

The hard-shelled seed obtained from the fruit of a tropical evergreen tree, genus Macadamia, native to Queensland and New South Wales in Australia. Macadamia trees grow to 15 m (49 ft) in height and have a dense foliage of glossy, leathery leaves.…

The cultivation of plants, primarily trees, that produce nuts. The term nut is used loosely. In general, a nut is defined as any edible fruit or seed enclosed in a hard shell. Botanically, a nut is a hard, indehiscent, one-seeded (nut), pericarp…

An agricultural crop of the genus Avena grown for its grain and straw in most countries of the temperate zones of the world. Oats (Fig. 1) belong to the order Poales (Cyperales), family Poaceae (Gramineae), and genus Avena. The most important crop…

Carica papaya, a semiwoody, usually single-stemmed, herbaceous plant cultivated for its fruit in tropical and subtropical regions. The papaya plant (Fig. 1) originated along the Caribbean lowlands of Mesoamerica and is now extensively and…

Chenopodium quinoa, an indigenous pseudocereal of the Andean region of South America. Quinoa (Fig. 1) was one of the first plants to be domesticated in South America, and it is now recognized agronomically as an important crop. It has received…

An annual cereal grass plant, Oryza sativa (family Poaceae), cultivated for its carbohydrate-rich grain. Rice is the major source of food for nearly one-half of the world's population. In China, Japan, Korea, the Philippines, India, and other…

A winter-hardy and drought-resistant cereal plant, Secale cereale, belonging to the grass family [Poaceae (Gramineae)], that is cultivated for its grain. Rye (Fig. 1) resembles wheat, with which it intercrosses to a limited extent. Rye is…

The plant Crocus sativus, which is a member of the iris family (Iridaceae) in the order Asparagales, and the spice derived from it. Originally a native of Greece and Asia Minor, saffron is now cultivated in various parts of Europe, India, and…

Members of the genus Ovis in the family Bovidae [order Artiodactyla (the even-toed, hoofed mammals)]. Sheep were possibly the first animals to be domesticated about 11,000 years ago in southwestern Asia. At that time, they were closely associated…

The lustrous protein fiber produced by silkworms (larvae of the silkworm moth); also the thread or cloth made from such fiber. Silk is a highly prized commodity by the consumer, even though certain manufactured fabrics now have some qualities that…

Any of a variety of widely cultivated grasses, especially Sorghum bicolor, grown for grain and herbage. Sorghum (Fig. 1) includes many widely grown grasses having a variety of names. Sorghum is known as guinea corn in West Africa, kafir corn in…

Glycine max, an erect annual legume native to China that is widely cultivated for forage and for its seed, which is a major source of vegetable protein and oil for human and animal consumption and for industrial usage. Introduced from China into…

Crops produced as major sources of sugar, syrup, and other sugar substances. Sugar crops include sugarbeet (also spelled sugar beet), sugarcane, sweet sorghum, sugar maple, sugar palm, honey, corn, and chicory. Sugar is a broad term applied to a…

The science of breeding, raising, and marketing swine. Any domesticated member of the genus Sus in the family Suidae is known as a swine (also hog or pig) [Fig. 1]. The agricultural enterprise of swine production is usually located in proximity to…

Any plant of the genus Nicotiana cultivated for its leaves, and the dried leaves of the plant. Most often, tobacco means a leaf product derived from the plant genus Nicotiana containing 1–3% of the alkaloid nicotine, which produces a narcotic…

Pathological conditions affecting shade and forest trees. Diseases of both shade and forest trees are caused by the same pathogens, but the trees differ in value, aesthetics, and utility. In forests, disease is significant only when large numbers…

The common name applied to about a dozen species of large deciduous trees in the genus Juglans, and the edible nut of these trees. Walnut trees are widely distributed over temperate North America and South America, southeastern Europe, and central…

A textile fiber made of the soft undercoat of sheep and various other animals, including angoras, goats, camels, alpacas, llamas, and vicunas. Wool is the most widely used animal fiber in the world. In addition, wool provides warmth and physical…

All buildings used on the farm for housing livestock and the farm family and for storing grain, livestock feed, and farm machinery. In the United States, today's farms are larger, more specialized, and more mechanized than those of the past, and…

A branch of meteorology that examines the effects and impacts of weather and climate on crops, rangeland, livestock, and various agricultural operations. The branch of agricultural meteorology dealing with atmospheric-biospheric processes occurring…

A branch of horticulture concerned with the selection, planting, and care of woody perennial plants. Knowing the potential form and size of plants is essential to effective landscape planning as well as to the care needed for plants. Arborists are…

A tree or shrub, sometimes called the tree of life, belonging to the genus Thuja of the order Pinales. Arborvitae is characterized by flattened branchlets with two types of scalelike leaves. At the edges of the branchlets, the leaves may be keeled…

Cynara scolymus (alternatively Cynara cardunculus var. scolymus), a herbaceous perennial plant, in the family Compositae (order Asterales), whose flower head is edible. The artichoke, also called the globe artichoke, has its origin in the…

A genus, Fraxinus, of deciduous trees of the olive family Oleaceae, order Lamiales. Ash trees have opposite, pinnate leaflets (see illustration), except in one species, F. anomala, which has only a single leaflet. About 65 species are found in the…

A dioecious perennial monocot (Asparagus officinalis) of Mediterranean origin belonging to the plant order Asparagales. Asparagus is grown for its young shoots or spears, which are canned, frozen, or cooked fresh as a vegetable. These aerial stems…

A tropical and subtropical evergreen tree, Persea americana, in the Lauraceae family (containing also the laurel of antiquity and the trees that yield commercial cinnamon and camphor), which bears a pulpy pear-shaped edible fruit. The avocado…

The common name of various perennial, ornamental grasses in the family Gramineae (Poaceae). There are approximately 90 genera of bamboo, with more than 1200 species. They have a wide distribution, but occur mainly in tropical and subtropical parts…

A large tropical plant of the genus Musa and its edible fruit. The banana belongs to the family Musaceae. The banana of commerce (Musa acuminata), which is believed to have originated in the Asian tropics, was one of the earliest cultivated fruits.…

An important grass plant of the genus Hordeum that is cultivated as a grain crop and whose seed is used as a cereal and to manufacture malt beverages. Barley (Fig. 1) is grown in nearly all cultivated areas of the temperate parts of the world and…

An annual herb (Ocimum basilicum) of the mint family (Lamiaceae; also known as Labiatae), grown from seed for its highly scented leaves. Basil is sold fresh or dried, and its essential oil is used in pharmaceuticals and flavoring. The genus Ocimum…

A member of the linden tree family (Tiliaceae) in the order Malvales. One species is known as the American linden or basswood (Tilia americana) [see illustration]. Basswood is a timber tree of the northeastern quarter of the United States and the…

A genus, Fagus, of deciduous trees of the family Fagaceae in the order Fagales. Beech trees can be distinguished by their long (often more than 1 in. or 2.5 cm), slender, scaly winter buds; their thin, gray bark, which is smooth even in old trees;…

Beta vulgaris, a cool-season biennial of Mediterranean origin belonging to the plant order Caryophyllales (Centrospermales). The red or garden beet (see illustration), also known as the beetroot, is grown primarily for its fleshy root; in…

The drug as well as the plant known as deadly nightshade (Atropa belladonna, which belongs to the nightshade family, Solanaceae). The belladonna plant (see illustration) is a coarse and poisonous perennial herb native to the Mediterranean regions…