Holly plant, showing the red berries © Rosie McPherson
How is holly dispersed?
All five thrush species found in Britain in winter love holly berries, dispersing the stone fruit through their droppings. Mistle thrushes are often highly protective of their tree, noisily guarding its berries against other birds.
How does it reproduce?
Holly is a diocecious plant – which means that it has separate male and female plants. Only the female plants produce berries, known as drupes. Botanically speaking, the fruit is the hard ‘stone’ at the centre, the exocarp is the red outer skin and the mesocarp is the fleshy orange layer in between.
What’s the difference between males and females?
The male has four prominent, pollen-bearing stamens that splay out in an ‘X’ shape, seen in spring and summer, from May. The female has a fat green ‘boss’ in the middle. This is the ovary, which forms the base of the yellowish stigma. There are also four stamens, but these don’t produce pollen. The flowering season is the same as the male.
Anything special about the leaves?
Holly leaves are evergreen. New low growth has more spines as it is within the browsing zone of deer – leaves that are above 2–3m are smoother-edged. Fallen holly leaves decay very slowly – look out for their paper-thin skeletons on the ground.
Who eats it?
Holly is a key foodplant for about 30 species of invertebrate, including the caterpillars of lovely insects such as the holly blue butterfly and privet hawkmoth.