The Ontogeny of Gender of Cupressus sempervirens L.

Abstract

Cupressus sempervirens, known as a monoecious species, is sequentially monoecious. Young trees and new growth are female. Stressed trees are male or show a tendency toward male predominance. Female cone production starts in some plants during year 2 of growth, and male cones are produced in some plants from year 4 on. Monoecy is completed at age 10. Young trees are pollinated only by adults, thus ensuring foreign pollination in the early years of reproduction. Unisexuality in the first years of reproduction reduces the reproductive effort. Under unfavorable conditions, trees are male or show a tendency toward maleness, contributing to the decrease of the reproductive effort.