Red-brown pasture moth

Systematic position. The red-brown pasture moth (Oncopera rufobrunnea) is a member of the Lepidoptera order and the Hepialidae family. It is a specialized pest known for its cryptic behavior, with larvae spending the majority of their lifecycle underground in tunnels, which makes it a challenging pest to monitor and control in agricultural settings.

Crops damaged. The primary targets of this pest are grasses and pasture plants. It causes significant damage to permanent pastures, hay fields, and perennial forage crops. In some instances, when populations surge, the larvae can encroach upon nearby grain fields, causing localized damage to seedling stages.

Biology and lifecycle. The lifecycle consists of eggs, larvae, pupae, and adults. The adult moths are short-lived and do not feed, focusing entirely on reproduction. After mating, eggs are laid in or near the soil. Upon hatching, larvae construct vertical burrows in the soil, which serve as their base of operations for feeding on the surrounding vegetation during the night.

Nature of damage and economic importance. Larvae emerge from their tunnels at night to feed on the foliage and stems of grass. They typically cut the plants at the base, leading to patches of bare soil within the pasture. Significant infestations result in severe degradation of the ground cover, reduced biomass production, and a decrease in the overall quality and carrying capacity of the land.

Protection measures. Effective control requires an integrated approach. Cultural management, such as intensive grazing at specific times, can help destroy eggs and inhibit larval survival. Chemical control using insecticides is sometimes necessary; however, application timing is critical and must coincide with the larvae's emergence on the surface. Natural biological control agents, including entomopathogenic fungi, also help maintain balance in the ecosystem.