Window screens, designed to keep insects out while allowing air circulation, can inadvertently become sites for insect reproduction. Understanding the types of eggs found on screens, the reasons insects choose these spots, and how to manage them provides practical solutions for homeowners. This article offers insights into identification and appropriate responses.
Identifying Eggs on Your Screens
Recognizing insect eggs on window screens depends on their visual characteristics, including color, size, shape, and arrangement. Green lacewing eggs are distinct, appearing as tiny, oval, white or pale green specks, each perched at the end of a delicate, hair-like filament. These eggs are typically laid in rows or small clusters, with stalks elevating them about an inch above the surface to protect them from predators and cannibalism among newly hatched larvae.
Stink bug eggs present a different appearance, typically laid in clusters of 10 to 30 or more. These eggs are often barrel-shaped, light green or light blue, and are commonly found on the undersides of leaves, though they can also appear on screens. The clusters are usually arranged in neat, geometric patterns.
Praying mantis egg cases, known as oothecae, are larger and more irregular in shape, with a frothy, papery, or foam-like texture that hardens upon drying. These cases are typically tan or brown and can contain hundreds of eggs, though they are less frequently found directly on screen mesh compared to nearby structural elements or plants.
Reasons Insects Lay Eggs on Screens
Insects select window screens to lay eggs for several biological and environmental reasons. The fine mesh offers protection, shielding delicate eggs from direct impact by rain or strong winds, and potentially making them less visible to some predators. This creates a secure and stable environment for their development. Screens also provide an elevated surface that allows for better air circulation around the egg mass. Some nocturnal insects, like certain moths, are drawn to light sources emanating from indoors, and may lay their eggs on screens near windows. Insects may also seek any stable, firm surface in proximity to food sources or suitable temperatures for their offspring.
Managing Screen-Laid Eggs
Managing insect eggs on screens depends on the type of insect. Lacewing eggs, for example, are generally considered beneficial. Their larvae, often called “aphid lions,” are voracious predators that consume garden pests such as aphids, mites, and small caterpillars. If you identify lacewing eggs, leaving them undisturbed can contribute to natural pest control.
Conversely, stink bug eggs are from a pest species known to damage agricultural crops and can become a nuisance when they enter homes. If these eggs are found, remove them by gently brushing or wiping them off the screen using a soft brush or a piece of tape, taking care not to crush them. Afterward, clean the screen with soapy water to eliminate any remaining residue or pheromones that might attract more insects.
To deter insects from laying eggs on screens, maintain clean screens and seal any gaps or tears in the mesh. Additionally, ensure proper weatherstripping around windows.