Every Term,
Defined.

Warning coloration that signals danger to predators. SLF adults display bright red hindwings when threatened to deter birds. The vivid scarlet-and-black pattern communicates "I taste bad" — though research on SLF palatability is still ongoing. This flash-display behavior is a key identification clue: a dull gray moth that suddenly reveals red underneath is almost certainly a spotted lanternfly.

A unit of accumulated heat used to predict insect development. For SLF, development models use a base temperature of 37.4°F (3°C) for nymph emergence and 50°F for adult activity. As temperatures accumulate above the base threshold each day, development progresses predictably. GDD models help researchers forecast when egg masses will hatch and when adult populations will peak — useful for timing control actions.

A sugar-rich liquid excretion produced when SLF feeds on plant phloem. As SLF extract sap, they process far more sugar than they can metabolize — the excess is expelled as honeydew that drips onto surfaces below. It coats leaves, decks, cars, and furniture with a sticky residue, and provides the food source that allows sooty mold to grow. A strong honeydew smell near a tree in late summer is a reliable indicator of active SLF feeding.

A developmental stage between molts in insects. SLF passes through four nymph instars before reaching adulthood. Each instar is larger than the last and is separated by a molt (shedding of the exoskeleton). The 1st through 3rd instars are black with white spots; the 4th instar is the dramatic red stage. After the 4th molt, the adult emerges with wings.

The immature form of SLF before adult wings develop. SLF nymphs go through four instars, emerging from eggs in April–May and reaching adulthood by July–August. 1st through 3rd instar nymphs are jet black with bright white spots; 4th instar nymphs are vivid red with white spots and black markings. Nymphs can jump several inches when disturbed and do not yet fly.

The process of egg-laying. SLF females typically lay 1–2 egg masses per season, depositing them on hard surfaces from September through November. A single egg mass contains 30–50 eggs arranged in rows beneath a mud-like waxy coating. Females will oviposit on almost any hard surface: tree bark, stone, metal, vinyl siding, outdoor furniture, and vehicles — which is a primary vector for human-assisted spread.

The plant vascular tissue that transports sugars produced by photosynthesis from leaves to the rest of the plant. SLF feeds by inserting piercing mouthparts into the phloem of stems and branches. This sap-feeding stresses the plant, depletes its energy reserves, and produces the honeydew that drips below. Repeated heavy feeding over multiple seasons can weaken or kill vines and young trees.

A black fungal growth (several species, including Capnodium and Fumago) that colonizes honeydew deposits left by SLF feeding. The mold itself does not infect plant tissue — it grows on the surface of leaves and stems, using honeydew as a food source. Heavy sooty mold coating blocks sunlight from reaching leaf surfaces, reducing photosynthesis and further weakening plants already stressed by SLF sap-feeding. It is often the most visible early sign of SLF infestation.

A method of applying systemic insecticide solution directly to the lower 12–18 inches of a tree's bark using a pump sprayer. The insecticide (typically dinotefuran mixed with a penetrant like Pentra-Bark) is absorbed through the outer bark and enters the tree's vascular system. Less precise than injection but useful for treating multiple trees efficiently. Effectiveness depends on bark thickness and moisture conditions.

A funnel-shaped trap that wraps around tree trunks to intercept SLF climbing upward. SLF nymphs and adults aggregate on tree trunks and travel vertically — circle traps exploit this behavior by channeling insects into a collection container. They are non-toxic, reusable, and effective during active season, but require monitoring and emptying. Positioning matters: install below the lowest branch and remove by late fall to avoid trapping beneficial wildlife.

A fast-acting systemic neonicotinoid insecticide used for SLF tree treatment. Available under brand names Safari and OptiSol, it is the preferred choice for active-season treatment because it translocates through tree tissue within 1–2 weeks — much faster than imidacloprid. Applied via soil drench, basal bark spray, or trunk injection. Use during active feeding season (May–October) for best results. Avoid applications near water or bloom-period flowering plants due to pollinator risk.

A widely-used systemic neonicotinoid insecticide available under brand names Merit, Bayer Tree & Shrub, and others. Slower to translocate than dinotefuran (4–6 weeks to reach effective levels), but provides long residual protection — up to a full season. Most commonly applied as a soil drench around the base of the tree. Best applied in spring before SLF activity peaks so the chemical has time to distribute throughout the tree. The most common tool used by arborists for SLF management.

An evidence-based approach to pest control that combines biological, cultural, mechanical, and chemical controls to minimize pest impact while reducing environmental harm. Applied to SLF, IPM might mean removing Tree of Heaven (cultural), deploying circle traps (mechanical), encouraging natural predators (biological), and using targeted systemic treatments only on high-value plants (chemical). IPM prioritizes efficacy and proportionality rather than defaulting to maximum chemical application.

An OMRI-listed physical deterrent applied as a fine particle spray to plant surfaces. When applied to stems and leaves, it creates an irritating, abrasive coating that deters SLF from landing and feeding. It is not toxic — it works mechanically, not chemically. Requires reapplication after rain. Particularly useful for grapevines and fruit trees where chemical residue is a concern. Brand name: Surround WP.

A small pressurized capsule used for DIY tree micro-injection of systemic insecticides. The capsule is inserted into a small drilled hole in the tree trunk and uses internal pressure to force the insecticide directly into the tree's vascular system. More targeted than soil drenches and bypasses potential uptake issues with compacted or dry soil. Commonly used with imidacloprid. The Mauget system is designed for homeowner use without specialized injection equipment.

Certified by the Organic Materials Review Institute (OMRI) as acceptable for use in certified organic production under USDA NOP standards. OMRI-listed SLF products include spinosad, Beauveria bassiana, kaolin clay, and some neem-based products. OMRI listing does not mean non-toxic — some OMRI-listed pesticides are still hazardous to pollinators or aquatic organisms. Always read label instructions regardless of organic certification.

An OMRI-listed insecticide derived from the fermentation of Saccharopolyspora spinosa, a soil bacterium. Spinosad is effective against SLF nymphs and has moderate effect on adults. It disrupts the insect's nervous system. Available in products like Monterey Garden Insect Spray and Entrust SC. Important caveat: spinosad is toxic to bees when wet but breaks down quickly once dry. Apply in the evening after bee activity ceases to minimize pollinator risk.

A pesticide that is absorbed by the plant and distributed through its vascular tissue (xylem and phloem), rather than remaining on the surface. When SLF feeds on a plant treated with a systemic insecticide, it ingests the chemical and dies. Systemics provide protection from the inside out, reaching parts of the plant that spray coverage cannot. The trade-off: systemics can be present in pollen and nectar, potentially affecting pollinators.

A parasitoid wasp native to Asia that lays its eggs inside SLF egg masses, killing the developing nymphs. Currently under USDA APHIS quarantine evaluation as a potential biological control agent. In its native range (China, South Korea), it parasitizes a significant proportion of SLF eggs. Before any biocontrol organism can be released in the US, USDA requires extensive testing to ensure it will not harm non-target native species.

An entomopathogenic (insect-killing) fungus that occurs naturally in soil. When spores contact an insect's cuticle, they germinate, penetrate the exoskeleton, and colonize the insect from within, killing it. Available commercially as BotaniGard ES, BotaniGard 22WP, and Mycotrol. OMRI-listed and effective against SLF nymphs and adults when applied directly. Less effective as a preventive systemic; best used as a contact spray during active infestation.

A geographic area under state or federal regulation that restricts the movement of SLF and potential host material — including nursery plants, cut wood, outdoor equipment, vehicles, and RVs that may harbor egg masses. Quarantine zones are established by USDA APHIS and/or state departments of agriculture when SLF is confirmed. Moving regulated materials out of a quarantine zone without inspection can spread SLF to new areas and may be subject to penalties.

The iNaturalist species identifier for Lycorma delicatula (spotted lanternfly). Using this ID in iNaturalist's observation URL lets you search all confirmed SLF sightings globally: inaturalist.org/observations?taxon_id=324726. With hundreds of thousands of citizen-science observations, this dataset is one of the most detailed range maps available for any invasive species. Researchers, land managers, and curious citizens all use it to track spread in near real time.

An invasive deciduous tree native to China, widely established across the eastern US, and SLF's preferred reproductive host. SLF will feed on dozens of host species, but returns to Tree of Heaven to breed and overwinter. Removal of Tree of Heaven is considered the highest-impact long-term management strategy — a neighborhood without Tree of Heaven can significantly reduce SLF population density even if SLF is present nearby. However, improper removal (cutting without treatment) causes aggressive sprouting from the stump and roots.

The United States Department of Agriculture Animal and Plant Health Inspection Service — the lead federal agency responsible for SLF quarantine regulations, interstate movement restrictions, and oversight of biocontrol research. APHIS coordinates with state departments of agriculture to establish and enforce quarantine zones, funds research programs, and manages the approval process for potential biological control agents like Anastatus orientalis. APHIS provides the legal framework within which state-level SLF programs operate.