Gypsy Moth Caterpillar Spotted in Westchester

Screen Shot 2018-04-13 at 2.35.01 PM

What is the Gypsy Moth?

An invasive bug native to Eurasia that is well known for the damage that is causes to trees. They prefer Oak Trees, Birch Trees and Willow Trees, but will also prey on a number of different shrubs and trees that are in close proximity.

A female Gypsy moth cannot fly; she will lay clusters of eggs on bark, rocks, or really any surface that is convenient.  Each cluster she lays can contain anywhere from 100-1000 eggs. In the springtime, larvae hatch from the eggs and hang out near the cluster until heavy winds come and carry them away. From there, they find their way to a host tree and feed on the leaves causing defoliation to occur.

History of Outbreaks

The gypsy moth was introduced to North America in 1868, and was first spotted in Connecticut in 1905.  While there is a known population in the forests of Southern New England, it typically remains contained and outbreaks are small and manageable.

There was however, one very notable outbreak that lasted nearly 20 years in Connecticut from 1960-1980. At the peak of the Connecticut outbreak, defoliation had occurred in 1.5 million acres of trees, which is nearly 80% of the state’s forestland!

Recent Siting

Our arborists here at Emerald Tree and Shrub Care were recently called to a property in Cortlandt Manor where a population of “caterpillars” had invaded last summer.  Upon inspection, we identified countless egg hatches throughout the oak and willow trees on the property. While we treated this specific property, it’s very possible that Northern Westchester could experience an outbreak this Spring.  Please keep your eyes peeled for eggs masses that look like this:


And call us immediately (914-725-0441) for help identifying and treating the issue before they become a major outbreak.

Spotted Lanternfly Poses Huge Threat

Screen Shot 2018-04-12 at 3.11.49 PM

Native to Asia, this sap-sucking insect was found for the first time in New York State on November 29, 2017. These insects change their appearance with each life stage, but adults are about 1 inch long.  Their outer wings are a muted gray color with black spots, very inconspicuous until they hop or fly and expose their bright reddish/orange inner wings. While their wings are their main distinguishing feature, the lanternfly is actually more likely to hop from surface to surface as opposed to fly.

Why is the Spotted Lanternfly so dangerous?

  • They have a very powerful ability to reproduce in mass quantities. Females lay between 30-50 eggs at a time, in what looks like a disgusting gray goop. With an average of two hatches per season, that means each female is creating roughly 100 new spotted lantern flies each year!
  • They are not picky about their host.  While their preferred host plant is the Ailanthus altissima, (Which is an invasive itself known as the tree of heaven) they will also feed on over 70 other plant species including grapes, hops and fruit trees. Not only can they hop around easily, they pose a threat to a variety of different industries.
  • As they suck the sap of a plant’s stems, leaves or trunk, they excrete a sweet honeydew secretion that coats the host plant and is a catalyst for the growth of sooty mold.
  • There are no known predators. Birds do not seem to like to eat them and no other predator has been identified, keeping their population relatively stable for the time being.

The USDA has recognized the serious threat that this insect poses, and in February 2018, they announced their commitment of $17.5 million to stop the spread of the Spotted Lanternfly.

What can you do to help?

  • Avoid quarantined areas where the insect has been spotted. Eggs are very easily transported on wood, plants, nursery stock, cars, furniture and waste.
  • If you see a Spotted Lanternfly in an area where it’s not known to exist, try and capture it in a closed container and report it to the department of agriculture.
  • Regularly check known host plants, like Ailanthus altissima trees, for egg masses and actual insects. Dusk is the perfect time to do this, because they tend to cluster on trunks of their host trees around this time.

For more information on the Spotted Lanternfly, read the USDA’s fact sheet,