Alternate Bearing:
Sequence of a high yield in one year followed by a low yield in the subsequent year. In woody perennials alternate bearing can be evident at different levels (branch, tree, orchard); its occurrence increases with plant age. Although the causes and regulation are endogenous to the plant, climatic events (frost, drought) often trigger the onset of alternate bearing. Typical alternate bearing species are apple, citrus, olive, pecan and pistachio.