Spotted lanternflies do not survive the winter as adults, but their resilient egg masses endure the cold months. This invasive insect, originally from parts of China and Vietnam, poses a threat to agriculture and various plant species in introduced areas like the United States. Understanding its life cycle is important for managing its populations.
Life Cycle and Winter Survival
The spotted lanternfly completes one generation each year, with its life cycle closely tied to seasonal changes. Adult lanternflies emerge in July and are active through the fall, engaging in feeding, mating, and egg-laying. Adults begin laying eggs from late September through the onset of winter, often until the first killing frost. Cold winter temperatures cause adult spotted lanternflies to die off.
Despite the demise of adults, the species overwinters in the egg stage. Females lay eggs in masses, covering them with a protective, mud-like substance that helps them withstand harsh winter conditions. These egg masses enter a state of diapause, a period of suspended development. The eggs remain dormant until warmer spring temperatures trigger them to hatch.
Recognizing Egg Masses
Since egg masses are the overwintering stage, identifying them is a practical step in managing spotted lanternfly populations. These masses are about one inch long and contain 30 to 50 eggs. When freshly laid, they appear as a creamy-white or light gray, putty-like substance, which later dries and turns a pinkish-gray or brownish color, resembling a splotch of dried mud or lichen. Over time, the protective covering may crack or wear off, revealing the individual, seed-like eggs beneath.
Spotted lanternflies are not particular about where they lay their eggs, choosing almost any smooth, hard outdoor surface. Common locations include tree trunks, branches, rocks, outdoor furniture, grills, fences, vehicles, firewood, recreational vehicles, and even children’s toys. Identifying these camouflaged masses in late fall, winter, and early spring before they hatch is key for control efforts.
Winter Control Strategies
Winter offers a window of opportunity to manage spotted lanternfly populations by targeting overwintering egg masses. From late fall, after adults have died off, through early spring before eggs hatch, individuals can actively search for and destroy these masses. This intervention can significantly reduce the number of nymphs that emerge in the spring. Reporting sightings of spotted lanternflies or their egg masses to local agricultural or extension services is also encouraged, as this information contributes to broader monitoring and management efforts.
A common method for destroying egg masses involves scraping them off surfaces. A credit card, putty knife, or similar flat, rigid tool can be used to scrape the masses with firm pressure, ensuring the eggs are crushed. After scraping, collect the eggs and place them into a sealed bag or container with rubbing alcohol or hand sanitizer. This ensures the eggs are thoroughly destroyed, and the sealed bag can then be disposed of in regular trash.