Invasive plants are the opposite of rare. A third of all the vegetation in the northeast, much of it invasive, hails from Asia, according to native plant scientist Dr. Doug Tallamy.
What's rare about invasives? The ability to stop them in their tracks.
There’s a mantra among invasive experts: controlling established invasives is maddeningly tough, but stopping them from becoming established in the first place is often quite possible.
Most invasive plants we battle have been here a century or more. It’s rare we have a chance to catch an invader just getting started. We now have such a chance. We can stop the Spotted Lanternfly from gaining a toehold in Granby and spreading further.
One bad bug
The Spotted Lanternfly (Lycorma delicatula) is “an exotic sap-feeding planthopper that has the potential to severely impact Connecticut's agricultural crops, particularly apples, grapes, and hops, and ornamental trees” says the Connecticut Agricultural Experiment Station (CAES), which issued a statewide quarantine in 2021 and renewed it in January this year. The quarantine attempts to limit SLF by requiring inspection and notification of items in areas of infestation and prohibiting their movement without a “phytosanitary certificate” that documents the absence of SLF. Quarantines have helped slow SLF’s steady spread, but need our help to succeed.
SLF stresses trees by puncturing bark and sucking sap. It also excretes a gooey “honeydew” that encourages sooty mold growth and attracts other insects. Adults can fly, but not far; most movement is via hitchhiking: laying eggs on a surface that is moved, usually by humans.
Spotted Lanternfly is native to China, India and Vietnam. It is thought to have arrived in the US as egg masses on a shipment of stone. Maps show its malignant movement from discovery in 2014 northwest of Philadelphia, radiating outward to 14 states since then, including much of New York. In Connecticut it followed rail lines into Fairfield and New Haven County towns; it’s been found in Massachusetts and in every county in Connecticut except Windham.
What does SLF like to eat? In short, Connecticut.
The babies (nymphs) like Red Maple, Sugar Maple, White Pine, Red Oak and White Oak -- about half the trees in Connecticut forests – and just about everything else as well.
As adults, their tastes become more refined. By late summer, they are focusing on their favorites: Tree of Heaven, grapes, and fruit trees.
A Heavenly Host
SLF’s favorite food is the Tree of Heaven (Ailanthus altissima), a vigorous, very invasive tree that commonly grows in clumps along field edges and in open areas. Its leaves, smooth bark and growth pattern are similar to native sumac, though it grows taller and flowers differently.
There are at least four clusters of Tree of Heaven in field edges at Holcomb Farm, including a massive specimen in the hedgerow across the field east of the farmhouse that was likely planted intentionally many decades ago. There’s a lively debate among local tree lovers about best ways to control Tree of Heaven, a particular challenge because cutting trunks to the ground encourages underground roots to send up a host of new trees 5, 10, 20 feet away.
On the bright side, Tree of Heaven is known among invasive geeks as a rare potential success story. Peter Picone, CT DEEP Wildlife Biologist, described successful control strategies at the CT Invasive Plant Working Group (CIPWG) symposium in November 2022. These included girdling (severing the living material under the bark of a mature tree, all the way around), careful cutting-and-painting with herbicide, and attentive followup with foliar treatment on popups yards away. The best time to girdle and poison appears to be soon after new leaves have emerged, when the roots have expended their resources and they have not yet begun to be replenished.
Control and Report
We can make Spotted Lanternfly an invasive success story rather than an out-of-control disaster.
In April and earlier, look for egg masses on trees, rocks and other smooth-ish surfaces like decks, houses and outdoor furniture -- 30-90 eggs in a wide gray mass, bumpy, a few inches wide and long, covered in a gray waxy coating. TAKE A PICTURE and REPORT your finding using this form. Then crush it to bits and look for more.
When they hatch in May and June, nymphs feed on all kinds of young stems and leaves nearby. Look for feeding nymphs – dozens of small, beetle-like black and, as spring turns to summer, larger and redder nymphs clustering on trees and new shoots. By late summer they are adult, gray and dull with folded wings when feeding but, aflight, easy to identify with spots and colorful rear wings. TAKE A PICTURE and REPORT using this form. Then kill ‘em and look for more.
We are the leaders we’ve been waiting for
If you like wine, or fruit, or trees, or Granby: keep your eyes peeled, report what you find, and take action. If we all work together, we can keep Granby free of the Spotted Lanternfly.
Resources:
Spotted Lanternfly | National Invasive Species Information Center
CT Spotted Lanternfly -- DEEP
Spotted Lanternfly - SLF -- CAES
Survey Status of Spotted lanternfly - Lycorma delicatula (2022)
NOT WANTED: Granby Conservation Commission's campaign to educate about and take action on invasive plants