Yellow-rattle

Scientific name: Rhinanthus minor

Brush through a wildflower meadow at the height of summer and you'll hear the tiny seeds of yellow-rattle rattling in their brown pods, hence its name.

Top facts

Stats

Height: up to 45cm

Conservation status

Common.

When to see

May to September

About

When the flowers of yellow-rattle fade, the brown calyxes (containing the sepals) in which the tiny seeds ripen can be seen and heard - they give a distinctive 'rattle', hence the common name. Yellow-rattle is an annual that thrives in grasslands, living a semi-parasitic life by feeding off the nutrients in the roots of nearby grasses. For this reason, it was once seen as an indicator of poor grassland by farmers, but is now often used to turn improved grassland back to meadow - by feeding off the vigorous grasses, it eventually allows more delicate, traditional species to push their way through.

What to look for

Yellow-rattle has yellow, tube-like flowers protruding from an inflated, green calyx, which appear May to September. It has serrated leaves with heavy, dark veins, which sprout opposite each other all the way up the stem. Its stems have black spots.