Spotted Lanternfly in Macomb County

Spotted Lanternfly (Lycorma delicatula) is poised to be one of the most concerning invasive pests in recent years. Originally from Asia, this planthopper has rapidly expanded its range in the United States and continues to be a significant nuisance for homeowners in the eastern United States. In Michigan, and specifically in Macomb County, increasing reports of Spotted Lanternfly sightings have heightened awareness among homeowners, landscape professionals, and arborists.

This pest is not a direct feeder on woody tissues like borers or canker pathogens, but its feeding behavior, mobility, and propensity to congregate in large numbers create significant stress for host plants. Furthermore, the sticky honeydew and subsequent sooty mold growth that result from heavy infestations cause additional landscape and property issues.

The ISA Certified Arborists at Owen Tree Service can help property owners identify and understand the risks associated with this invasive insect and formulate a responsible and effective treatment strategy.

What Is Spotted Lanternfly

Spotted Lanternfly (SLF) is an invasive insect that feeds on the sap of a wide range of plants. Adults are striking in appearance, with light gray wings marked by black spots and bold red patches. Nymphs pass through several juvenile stages, starting as small black insects with white spots and later developing red patches before adulthood.

Spotted Lanternfly is highly mobile and tends to congregate in large numbers on favored host plants. Its feeding does not directly bore into wood, but the collective sap extraction can significantly weaken trees and shrubs over time.

These pests excrete a sticky, sugary substance known as honeydew, which encourages fungal growth and creates additional stress for plants.

Why Spotted Lanternfly Is a Concern in Macomb County

Spotted Lanternfly has been confirmed in several Michigan counties, and sightings in Macomb County have increased due to natural spread and accidental human transport. Because SLF feeds on a wide variety of host plants, its presence has implications for urban and suburban landscapes, natural areas, and orchards.

Common host plants of Spotted Lanternfly include:

• Tree-of-heaven (Ailanthus altissima)

• Maples

• Willow

• Birch

• Apple and other fruit trees

• Grapevines

• Black walnut

• Poplar

• Birch

Although not all susceptible hosts are equally preferred, the sheer diversity of plants on this list means that landscapes, woodlots, and nurseries in Macomb County are all at risk.

How Spotted Lanternfly Causes Damage

Spotted Lanternfly feeds by piercing the plant’s vascular tissue and extracting sap. When infestations are heavy, this continuous feeding can reduce the tree’s ability to produce food, weaken structural integrity, and lead to reduced vigor over time.

Some key effects of SLF feeding include:

• Stress from repeated sap loss

• Reduced growth and canopy density

• Increased susceptibility to other pests and pathogens

• Production of honeydew

• Growth of sooty mold on leaves and stems

• Sticky residues on outdoor surfaces, vehicles, decks, and structures

Honeydew buildup can be especially problematic in high traffic areas, creating nuisance conditions for homeowners and businesses alike.

Identifying Spotted Lanternfly Signs and Life Stages

Accurate identification is often the first step in effective management. Recognizing life stages helps determine appropriate timing for monitoring and treatment.

Nymph stages (first to third instars):

• Small black insects with distinct white spots.

Nymph stages(later instars):

• Red patches begin to appear along with white spots.

Adult stage:

• Wings are gray with black spots.

• Wing tips are checkered black and white.

• Hind wings are red with black spots and a white band.

Egg masses:

• Brownish-gray, often deposited on tree bark, rocks, or outdoor objects.

• Look like smudges of putty or mud, approximately one to two inches long.

Identifying these signs on or near susceptible host plants helps differentiate SLF infestation from other insect pressure.

A current-year egg mass beneath an old egg mass on tree of heaven. | Emelie Swackhamer, Penn State Univ., Bugwood.org

Monitoring and Early Detection

Routine monitoring is essential for early detection. Property owners should inspect:

• Preferred host tree trunks

• Stems and branches of large shrubs

• Leaf undersides

• Outdoor furniture, patios, and equipment (egg masses can be on nearly any surface)

Because SLF adults are strong jumpers and can fly short distances, sightings in one location often lead to discoveries on nearby plants. Early detection allows for quicker intervention before populations become large.

Treatment Approaches in Macomb County Landscapes

Managing Spotted Lanternfly typically involves a combination of physical, chemical, and habitat based techniques. No single method eliminates all individuals, but an integrated approach reduces populations and minimizes stress on plants.

Physical and Mechanical Controls

Physical removal is often a good place to start:

• Scrape or remove egg masses from trunks, stones, outdoor furniture, and other surfaces

• Use sticky bands on tree trunks to capture moving nymphs and adults (monitor regularly to prevent unintended capture of wildlife)

Egg mass scraping is especially important in fall and winter, when egg cases remain visible even after adults have died off.

Foliar and Trunk Spray Applications

Foliar sprays and trunk sprays target active feeding stages of Spotted Lanternfly, especially from late spring and into the fall. These sprays interfere with insect nervous systems or feeding behavior and reduce local impact when populations are concentrated on host plants.

Spraying for Spotted Lanternfly is most effective when applied by trained professionals who understand:

• Proper timing

• Coverage requirements

• Environmental safety considerations

• Non-target plant species and beneficial insect protection

Timing and product selection are critical, as SLF mobility and life stage timing vary with weather conditions and the time of year.

  Spotted Lanternfly nymphs. | Lawrence Barringer, PA Dept. of Ag., Bugwood.org

Why Timing Is Never Exact in Michigan

Weather in Macomb County is unpredictable and temperature fluctuations, extended rain events, drought periods, and early or late seasonal transitions all affect the timing of Spotted Lanternfly development.

Because of this, timing treatments based on strict calendar dates is unreliable. Monitoring insect development, host plant activity, and weather patterns creates more accurate treatment windows and reduces unnecessary applications.

Cultural and Landscape Best Practices

Reducing the impact of Spotted Lanternfly also involves habitat management:

• Managing or removing tree of heaven (a highly favored host) when feasible

• Improving overall plant health through proper watering and soil care

• Avoiding plant stress that makes hosts more attractive to SLF

• Encouraging natural predators and beneficial insects when possible

A healthy landscape is less susceptible to major outbreaks and better able to tolerate pest pressure.

Realistic Expectations for Control

Complete eradication of Spotted Lanternfly from a landscape is unlikely once populations are established. The goal of treatment is to reduce feeding pressure, protect high value trees and shrubs, and improve quality of life for people and pets in the area. Results of SLF treatments will vary based on:

• Scale of infestation

• Timing of detection

• Environmental conditions

• Host plant species

• Treatment methods and monitoring

A realistic approach focuses on reducing numbers, protecting plants, and preventing severe decline rather than expecting total elimination.

Why Professional Support Matters

Proper identification, monitoring, and treatment selection are essential for successful management. Misidentifying insect pressure can lead to ineffective treatments and wasted resources.

Our ISA Certified Arborists will assess plant species, site conditions, pest presence, and environmental factors before recommending treatment options that align with plant health and property goals.

Professional treatment plans are designed to minimize risk to non-target insects, children, and pets while protecting the plants being attacked by Spotted Lanternfly.

Conclusion

Spotted Lanternfly is a growing concern in Macomb County landscapes due to its wide host range, mobility, and potential for significant feeding pressure. While it is unlikely that any single method will eliminate every individual from a property, integrated strategies involving physical removal, foliar sprays and healthy landscape practices can reduce SLF numbers and protect high value plants.

Early detection, monitoring, and professional management help reduce stress on host plants like maple, birch, apple, and others. By combining science-based treatments with practical expectations and long-term plant care, property owners can protect their landscapes and enhance plant health even in the face of this emerging invasive pest.

Our ISA Certified Arborists can develop a customized plan that addresses Spotted Lanternfly and other landscape threats based on plant needs, site conditions, and long-term goals. To set up an inspection of your property send us a message or give us a call at 800-724-6680.