Chrysanthemum lace bug

The Chrysanthemum lace bug (Corythucha marmorata) is a member of the Tingidae family within the order Hemiptera. This pest is named after the intricate, lace-like appearance of its wing covers. These minute insects are significant pests in ornamental horticulture, characterized by their ability to cause extensive damage to foliage by feeding on plant sap.

This species primarily targets plants in the Asteraceae family, including chrysanthemums, asters, sunflowers, and ragweed. Because of its polyphagous nature, the lace bug is a constant threat in both greenhouse and outdoor environments. Once established, they can spread rapidly through a garden or nursery, often going unnoticed until the symptoms of damage become severe.

The lifecycle of the insect follows a process of incomplete metamorphosis, consisting of egg, nymph, and adult stages. Females lay clusters of eggs on the underside of leaves, often covering them with a brownish secretion. Development from egg to adult takes only a few weeks under warm temperatures, allowing for multiple overlapping generations throughout the growing season.

Damage caused by the Chrysanthemum lace bug is distinct. They feed by inserting their piercing-sucking mouthparts into the leaf tissue, which results in characteristic stippling or bleaching of the leaves. Heavy infestations result in premature leaf drop, stunted plant development, and a general decline in the plant's health. Their dark, varnish-like excrement on the underside of leaves is a diagnostic sign of their presence.

Effective management strategies rely on a combination of cultural and chemical interventions. Cultural practices such as removing infested plant debris and controlling host weeds help reduce population numbers significantly. For chemical control, applications of systemic insecticides are generally recommended when nymphs are present. It is crucial to ensure thorough coverage, particularly on the undersides of the leaves, to achieve the best results in pest suppression.