Pollination: Buds, Flowers and Fruit
In Eucalypts in the sequence of development from bud to mature flower the sepals and petals have been replaced by a cap called an operculum.
At flowering time the operculum lifts away revealing the sometimes brightly coloured stamens to which insects and birds are attracted.
Following fertilisation of the egg (deep inside the ovary of the flower) by the sperm from the pollen grain, an embryo develops.
This embryo is housed within a developing seed, and at the same time the ovary develops into a fruit.
In eucalypts this fruit is woody and is termed a capsule.
This capsule protects seeds from predation and prevents overheating of the seeds in the event of a bushfire.
Top: Inflorescences (flowers in threes) of Eucalyptus pulverulenta
in bud stage showing outer (withered and brown) and inner cone-shaped opercula.
Bottom: The sequence of floral and fruit development in eucalypts.
