Ash flowers in March – with all images and text taken from the book Field Guide to the Trees of Britain and Europe published by Reed New Holland in 2017, author Alan Birkett and ISBN 9781921517839. The Common Ash tree produces flowers in March before the leaves. 

Common Ash tree male flowers
Common Ash tree male/female flowers

The first photo shows male flowers in March, before the leaves. Ash flowers have no petals. Some trees have only male flowers, some only female and some have flowers that have male and female parts. This photo of a male flower cluster shows the purple anthers that split open to release pollen onto the wind. The second photo shows flowers that have male and female parts. It shows the female styles and stigmas sticking up above the male anthers. When (male) pollen falls on the (female) stigmas, fertilisation takes place and fruit formation begins. Stigmas on the flower are not receptive to pollen when it is being released by the same flower. This avoids self-fertilisation.

Comon Ash tree female flowers
Common Ash tree fruit

The first photo shows fertilised female flowers in April. The purple fruits are just starting to form and the leaves are just coming out. The second photo shows how the Ash fruits, known as keys, hang down in bunches in July. Each fruit is technically called a samara. The word refers to any dry fruit which has flattened wings attached to it to help in its wind dispersion.