Restoring the Soil - Canadian Foodgrains Bank

78Annex 1: Glossary of Agricultural TermsLegume: A plant with seeds that grow inside an elongated pod. These plants areparticularly important in agriculture since, through a natural process, they takenitrogen out of the air and make it available to other plantsMonocrop: A crop that is grown alone in a field at a given timeNitrogen: A crop nutrient that is probably the greatest limiting factor to soil productivityaround the world. It is becoming a more and more expensive part of chemicalfertilizer because of the increasing price of energy around the worldOpportunity cost: The money or time you lose (that is, the “cost”) by choosing oneoption that eliminates the possibility (the “opportunity”) of taking advantage ofanother optionOrganic matter: Anything that, in its previous form, was part of a living organism,such as parts of dead plants, bodies of dead animals, urine and manurePerennial: A plant whose natural lifetime is two years or morepH: A measure of acidity or alkalinity. A soils’ pH will affect almost all plants’ growth,especially if the soil is either extremely acidic or extremely alkalineRelay crop: A crop that is planted in a field where another crop is growing within amonth or two of the initial crop’s being harvestedRhizobium: A microorganism that often grows on the roots of legumes and fixesnitrogen. It takes nitrogen out of the air and puts it in the soil in a form that plantscan accessRotation: A cropping system in which one crop is followed by another, or severalothers, in a systematic way. The crop sequence usually being designed to maintain soilfertility and reduce insect pests and diseasesSynchronization: The timing of the application of nutrients to the soil so they willprovide the amount and kind of nutrients a crop will need at any given stage of itsgrowth