A Sweet Tradition Worth Protecting: Maple Syrup and Invasive Species

This blog is brought to you by SLELO PRISM’s Pledge to Protect. 

Picture a crisp morning in New York: sunlight streaming through leafless branches, a steaming stack of pancakes on the table, and warm maple syrup slowly cascading down the sides. That rich, familiar sweetness comes from one remarkable tree—the sugar maple. But what if the future of maple syrup wasn’t guaranteed?

What's The Issue?

Invasive pests like the spotted lanternfly, spongy moth, and longhorned beetle can have negative impacts on our natural ecosystems such as reducing the health of the very trees that produce this golden delight. Protecting sugar maples means protecting the future of maple syrup. You can help by learning to identify and report these invasive insects—which helps to ensure that forests can support this sweet tradition for generations to come. 

March is Maple Month, the perfect time to celebrate this beloved treat. During Maple Weekend, held across the last two weekends of March, you can visit sugarhouses throughout New York to see how syrup is made, sample fresh maple products, and bring home the season’s sweetest flavors.

What You Can Do To Help

• Learn to recognize the spotted lanternfly, spongy moth, and the longhorned beetle.
• Watch for signs of infestation when you visit sugarbushes, farms, and encounter sugar maple trees across the state.
• Report observations to NYiMapInvasives.org.

Spotted Lanternfly

The spotted lanternfly (SLF) (Lycorma delicatula) is an invasive insect from Asia that has made its way to New York State, with the highest concentrations found in New York City and the Lower Hudson Valley. This pest spreads easily by hitching rides on vehicles and transported materials, making containment a challenge.

SLF feeds on over 100 plant species, including sugar maples. While it tends to favor silver and red maples, its feeding habits can still threaten the health of sugar maples, potentially impacting maple syrup production.

Identification:

• Adults (July–Cold Weather): About an inch long with greyish forewings, red hindwings, and distinctive black spots. Their upper wings have dark bands with white stripes.
• Nymphs (Spring–Summer): Start as small black insects with white spots, turning red before maturing into winged adults.
• Egg Masses (Fall–Winter): Laid in rows and covered with a white, waxy coating that helps them blend into outdoor surfaces, making them easy to overlook.

Signs of Infestation: 

• Sightings of SLF adults, nymphs, or egg masses.
• Sticky honeydew buildup beneath infested plants, often leading to black sooty mold growth.
• Sap oozing from tree wounds, which may appear wet and give off a foul odor.

What to Do:

• Take clear photos of the insect, egg mass, or infestation. Include a size reference, such as a coin or ruler.
• Capture the SLF and place it in a sealed bag, then freeze it. Alternatively, preserve it in a jar with rubbing alcohol or hand sanitizer. 
• If you find SLF on a vehicle or outdoor gear, scrape off and destroy egg masses before traveling to prevent accidental spread. Crush or dispose of live insects.

Report findings to NYiMapInvasives.org, fill out a Sighting Form, or email spottedlanternfly@agriculture.ny.gov.

Longhorned Beetle

The longhorned beetle (Anoplophora glabripennis) is an invasive wood-boring insect native to Asia that poses a serious threat to hardwood trees, especially maples. While longhorned beetles were detected and eradicated in Brooklyn in the late 1990s, New York’s global trade connections mean there’s always a risk of reintroduction. An infestation could devastate sugar maples, impacting both forests and the maple syrup industry.

Identification:

• Adults (July–Fall): About 1.5 inches long with distinctive black and white striped antennae and shiny black wing casings covered in white spots.
• Larvae: Grow up to 2 inches long, with off-white, segmented bodies and brown heads.

Signs of Infestation:

• Round, ½-inch exit holes in tree trunks and branches, appearing from late July onward.
• Egg-laying sites: Small, round depressions in the bark.
• Oozing sap from egg-laying sites and exit holes.
• Deep exit holes—if you can insert a pencil at least an inch deep, it could from longhorned beetle. 
• Sawdust-like frass accumulating at the base of the tree or on branches.

What to Do:

• Take pictures of the infestation signs as described above (include something for scale such as a coin or ruler)
• Note the location (intersecting roads, landmarks or GPS coordinates)

Email DEC Forest Health at foresthealth@dec.ny.gov, call the tip line at 1-866-702-9938, or report the infestation to iMapInvasives.

Spongy Moth

he spongy moth (Lymantria dispar) is an invasive moth originating from Europe and Asia. Spongy moth was inadvertently introduced to the United States in the late 19th century and has since spread extensively. Although spongy moths don’t target maple trees, outbreaks pose a significant threat to forests and urban landscapes across New York.

Identification:

• Egg Masses: Spongy moths lay egg masses on trees and various flat surfaces. These masses are light brown, covered with fine hairs, and can be found on tree trunks, branches, firewood, and even outdoor furniture. 
• Caterpillars: The larvae are identifiable by their five pairs of blue spots followed by six pairs of red spots along their backs. They are voracious feeders, primarily active in the spring.
• Adults: Male moths are brownish with a wingspan of about 1.5 inches and have feathery antennae. Females are larger, whitish with black markings, and notably, they cannot fly.​

What to Do:

• Scrape found egg masses off using a putty knife or thick plastic card. Extend your reach using telescoping extension poles with attached scrappers (view photos of this technique).
• Dispose of eggs in a container with some dish detergent, hand sanitizer, or rubbing alcohol.

About SLELO PRISM

SLELO PRISM (St. Lawrence–Eastern Lake Ontario Partnership for Regional Invasive Species Management) is part of New York State’s collaborative PRISM network, which works to prevent, detect, and manage invasive species to protect native habitats, biodiversity, and freshwater resources. Hosted by The Nature Conservancy, SLELO focuses its efforts in Oneida, Oswego, Jefferson, Lewis, and St. Lawrence counties.

The statewide PRISM network is funded by the NYS Environmental Protection Fund and coordinated by the NYS Department of Environmental Conservation and partners. Its mission is to provide a unified, statewide approach to invasive species management by coordinating local partners, training volunteers, conducting outreach, and implementing control and restoration efforts across eight regions.

Learn more about SLELO PRISM at www.sleloinvasives.org.