At this time of year it's worth looking closely at deciduous trees, including our native trees, which are producing the flowers which later turn into seeds, nuts or fruit. Most are not flamboyant and some are scarcely noticeable.
Oak trees produce male flowers as dangling catkins which appear at the same time as the new leaves start to develop. The female flowers are on the same tree as the male and appear on the tip of the shoot, but are tiny and inconspicuous with red stigmas.
Autumn fruit: acorns.
Hazel catkins (left) are well-known and are the male flower. The female flower is again a very inconspicuous little red flower which opens more or less as the catkins are shedding their pollen.
Autumn fruit: nuts.
Ash trees (right) have flowers without petals or sepals, which open in April before the leaves.
Autumn fruit: ash keys
Holly (left), an evergreen tree, has flowers which appear in bunches in the leaf axils, quite crowded together. they are purplish white and the male and female flowers occur on different trees.
Autumn fruit: red berries.
Maples (Acer family) right, have flowers which hang down in long-stalked bunches before the leaves appear, and are much more obvious than any of those mentioned above.
If you start looking closely at the trees in the spring you might be surprised by what you see.