The underside of a leaf of a hybrid garden lily, with eggs of the lily beetle (Lilioceris lilii). The picture shows (centre) a group of ten eggs, and below to their right, a newly hatched larva. The dark patches on the leaf are areas where the epidermis has been damaged as the larvae begin to feed. Later, the larvae will cause extensive damage to the plant's foliage, camouflaging themselves against predators with their own frass (faeces), so as to resemble bird droppings (top, to right). Lily beetles are a serious pest; the adults will eat both foliage and flower tissues, and the larvae can defoliate plants.The larvae pupate in the soil, and adults over-winter at ground level in plant debris. One effective, non-chemical control is hand-picking of the very conspicuous adults as soon as they appear in early Spring. A Japanese species, L. lilii was first found breeding in the UK in 1942. |