Caliche—A rocklike deposit of calcium carbonate (lime) beneath the soil surface. This condition is found in the dry areas of the Southwest.
Cambium—A thin layer of tissue-producing cells between the bark and the sapwood of a woody plant.
Caterpillars and worms—Pests that come in hundreds of varieties. Most are moth and butterfly larvae that feed on foliage.
Chlorosis—The yellowing of leaves (especially between the leaf veins) caused by the lack of iron or other nutrients.
Complete fertilizer—A plant food containing the three primary elements: nitrogen, phosphorus, and potassium.
Compost—Organic matter that has been decomposed by a process of fermentation. An excellent soil conditioner, compost is also a mild fertilizer. The most important organic tool.
Conifer—A plant that produces seeds in cones and is usually evergreen. Their leaves may be needlelike (e.g., pines) or scale like (e.g., junipers).
Cool season grasses—Grasses that natively grow in cool climates, used here in shade areas and for winter over seeding (e.g., ryegrass, bent, fescue, Poa trivialis).
Corm—Like a bulb; thickened underground vertical stem which produces roots, leaves, and flowers during the growing season. It differs from a bulb in that food is stored in the solid center tissue, whereas food is stored in scales of bulbs.
Crown gall—A bacterial disease causing deformation at the base of plants at the ground line; especially prevalent on conifers and members of the rose family.
Cultivar—A horticultural variety that has originated under cultivation. Cultivar names are now formed from not more than three words and usually distinguished typographically by the use of single quotation marks, e.g., ‘Early Black.’
Cultivate—(1) To grow or plant domestically. (2) To hoe or dig around a live plant for the purpose of eliminating weeds and breaking up crusty soil.
Cutworm—Night-feeding worm that is particularly destructive to tender bedding plants.