These jewelled beetles, gleam with burnished colours: gold, jade, copper, ruby, depending on how the light falls. Head, thorax and abdomen seem patinated in precious metals and gemstones. Though the beetles lay their eggs mainly on docks, they can also be found on bloody sorrel and  rhubarb.
A female dock beetle clambers across the undulations of a leaf, her abdomen so swollen with eggs that her wing cases are displaced. This doesn’t stop a smaller male trying to mate; her notched antennae twitch as she drags him around with her. She can lay 1,000 eggs, tiny rugby balls that start pale and turn orange when about to hatch. It’s the larvae’s second instar stage that does so much damage to the leaves.
Try to catch a dock beetle and it will curl up its legs and drop instantly, falling to the ground or rolling like a pea into the centre of a leaf. An organic gardener would pick them off; an organic farmer sees them as an ally. Docks are not wanted in hay meadows, their stalks tough and stringy, their seeds plentiful. By shredding dock leaves before the plant flowers, the beetles act as a form of biological control.
