Pollination, flowers, and seeds
Sexual reproduction
Tree reproduction in the guide begins with seed production and pollination.
Trees can be monoecious, with male and female flowers on the same plant, or dioecious, with separate male and female plants.
Pollination moves pollen from anther to stigma. In the UK this mainly relies on wind and insects. Trees have evolved ways to reduce self-pollination and increase genetic mixing.
Monoecious and dioecious
Monoecious
Male and female flowers on the same tree.
Examples in the guide: oak, pine, birch, hornbeam.
Dioecious
Male and female flowers on separate trees.
Examples in the guide: willow, cedar, yew, mulberry.
Wind pollination strategies
- Producing very large amounts of pollen
- Using dangling catkins that shake pollen loose easily
- Flowering before the leaves emerge so pollen can travel more freely
Key takeaway
Pollination is not random chaos. Trees use timing, flower structure, and release strategies to improve success.
Knowledge check
What is the difference between monoecious and dioecious trees?
Monoecious trees have male and female flowers on the same plant. Dioecious trees have male or female flowers on separate plants.