Glossary for agroforestry

Compiled and edited by Peter Huxley and Helen van Houten, International Centre for Research in Agroforestry - 1997

yield

Plant part harvested and the quantity of it. In agriculture, necessarily related to a specified crop or crops or to a group of animals or to an area, and to a period of time. For multipurpose trees, the amount of each specified part harvested. See also production

yield class

1. The potential or actual yield of a forest, calculated as the total volume of wood produced divided by the age when maximum mean annual increment is achieved. Usually expressed as cubic metres per hectare per year.

2. A way of expressing the productivity of a particular tree crop on a particular site. It is signifiedby a number that represents the annual production of timber averaged over its economic lifetime or, more correctly, to the age at which the 'mean annual increment' culminates. Thus a crop of 'yield class 10' produces 10 cubic metres of timber per year on average. See also current annual increment, mean annual increment, site class