The following trees are at highest risk for Spotted Lanternfly (SLF) attack: Maples (especially Red and Silver), Willows, Walnuts, Japanese Snowbells, Birch, Locust, Grapevines and several varieties of fruit trees. With SLF attracted to such a wide variety of trees, Giroud recommends protecting only high-risk trees that are most valuable to your landscape. Tree of Heaven (Ailanthus), an invasive weedy tree from China, is also a favorite host for Spotted Lanternfly. Ailanthus attracts SLF like a magnet and should be destroyed if it is on or near your property.
Spotted Lanternfly (SLF) damage trees primarily in the later stages of its life.
Damage in Nymph Stage: May-July
SLF Nymphs are mobile and tend to go after plants instead of trees. That’s because their mouth parts can’t pierce tree bark. As a result, they spread all over the yard searching for plant stems and leaves that they can easily feed on. Nymphs get progressively more harmful as they evolve through 4 Instar stages.
– 1st and 2nd Stage Instars can damage perennials, like Salvia, when they are present in high numbers and don’t move on. However, most plants recover quickly.
– 3rd and 4th Stage Instars begin feeding on leaf petioles and heavier twigs. By the 4th stage, Instars are 3 times bigger and high populations can start causing permanent damage. These larger Nymphs feed more heavily which can cause yellowing leaves, twig die-back and loss of critical plant nutrients.
Damage in Adult Stage: July-November
Tree damage from Spotted Lanternfly adults can range from oozing sap, wilting, leaf curling, defoliation and even tree death. Winged adults can attack a single tree in swarms. With so many feeding at once, the droppings (aka “Honeydew”) can look like rain pouring down on everything under the tree. Once there, black, sooty mold begins to grow and creates a sour stench. Even worse, the odor attracts stinging wasps.
See Spotted Lanternfly damage for more information.
Spotted Lanternfly (SLF) requires different controls at each stage of its 3-stage life cycle. Giroud has been working closely with Penn State, the PA Department of Agriculture and the USDA to determine the best treatments and timing for control.
a) Control in Nymph Stage: May-July
The challenge with Nymph control is that the pests are very mobile and don’t stay in one place very long. That’s why, research has determined that the best time to control Spotted Lanternfly is at the adult stage.
However, there is an exception. Nymph control may be warranted if the population is high enough to cause feeding damage (wilting stems). Or, if Nymphs are focusing heavily on individual plants.
Here are two “Do It Yourself” (DIY) Options for the Nymph Stage:
– Spot Treatments: Use a quick knockdown product like Neem Oil or insecticidal soap. Follow label directions carefully. Spray the oil or soap directly on the Nymphs. It will kill the pests on contact. Spot treatments will not have a significant impact on the larger SLF population.
– Traps: As an alternative to chemical controls, use Circle Traps or Sticky Bands to catch the nymphs as they climb up and down the tree.
It’s important to note that Nymphs are your early warning sign that the Adults are coming. By the Adult stage, professional treatment will be needed to protect high risk trees and avoid the mess created by SLF droppings.
When swarms of Adult SLF invade our yards in July/August, demand for control is going to surge. We expect the need for treatments will far exceed our capacity. To ensure you get on our treatment schedule, call now to have your Giroud Arborist evaluate your situation and determine the best way to control SLF on your property.
See “Controlling Spotted Lanternfly in the Nymph Stages” for more information,
b) Control in Adult Stage: July-November
SLF is most vulnerable to chemical control at this stage.
– July-September: A Giroud PA Certified Plant Healthcare Technician will spray Dinotefuran to the trunk of the tree. The treatment is absorbed up into the branches and crown within 1-3 weeks. It kills the adult SLF when they feed on the tree. The treatment lasts about 60 days.
– September-November: A Giroud PA Certified Plant Healthcare Technician will spray Bifenthrin around the top canopy of the tree. This treatment kills the adult SLF on contact as they climb higher into the tree’s branches for mating and feed on treated areas. The treatment lasts about 30 days.
c) Control in Egg Mass Stage: November-April
Adult females lay eggs in the fall. Eggs are laid on tree trunks or just about any flat surface. Adult females cover the eggs in a secretion that that looks like dirt or clay and protects them from predators over the winter months. This protection also makes it difficult to treat and kill the eggs chemically. If you find egg masses on your trees, destroy them by scraping the masses into a bag with rubbing alcohol or hand sanitizer. Also, this is an early warning sign that SLF is on your property. Schedule a free evaluation with your Giroud ISA Certified Arborist. He will set up a plan to kill the SLF on your trees when they are in the adult stage.
See this Giroud blog post on destroying egg masses for more information.
d) Ailanthus Tree Removal: Year-round
How do I remove Tree of Heaven (Ailanthus)?
If there are any Tree of Heaven on or near your property, they will attract SLF. Giroud has the special PA permit required to destroy these trees. We recommend removing the tree and grinding the stump down as deeply as possible. After removing the Ailanthus tree and stump, sprouts may still pop up on your property. To remove them, you can simply grab the shoot by its base and pull upward gently to remove the sprout and all of its roots. If the sprouts are too numerous, Giroud can apply an herbicide treatment to kill them.
e) Fertilization: Spring or Fall
SLF feeding can wound and deplete vital nutrients from your trees. Fertilizing replaces lost nutrients to promote healing and build strength.
See Spotted Lanternfly Control for more information.
The cost of Spotted Lanternfly treatments is directly related to how many trees need treatment and the size of each tree. These two factors determine the amount of insecticide needed to protect each tree and the amount of time required to do the treatments.
Ailanthus Tree removal cost can vary dramatically. The ISA Certified Arborists at Giroud Tree and Lawn explain the top 5 factors that can affect the price for tree removal:
1. Tree Size
2. Proximity to electrical hazards: Is the tree growing near electrical wires or other hazards?
3. Ease of Access: Is the tree located where equipment can be staged near the tree?
4. Equipment Required: Is special equipment such as a crane or bucket truck needed to complete the job safely?
5. Property Safety: Is the tree close to a house or other valuable structure that may require special rigging to remove the tree safely without damage to your property?
All Spotted Lanternfly applications are safe for children & pets. Giroud recommends that no children or pets be allowed in the application area during or for an hour after the application is made. This ensures that the application dries and adheres to the target areas.
Spotted Lanternfly is a leafhopper insect that feeds on trees, causes damage to properties, and attracts dangerous, stinging wasps.
Spotted Lanternfly was first discovered in the US in 2014 in Berks County, PA. It is thought that this insect was accidentally brought over to the US on shipping materials from Asia.
Since Spotted Lanternfly is not native to the United States, it has no known predators here to kill it and limit the population.
Spotted Lanternfly feeds in swarms and has a voracious appetite. Feeding in such large numbers damages trees. As it feeds, SLF shoots out sour smelling droppings called “honeydew.” The Honeydew can fall like rain and land on anything under the trees including cars, hardscapes, pools and play equipment. Additionally, these droppings turn into black, sooty mold that attracts stinging wasps, hornets and bees. To make the situation even worse, SLF multiplies rapidly. One adult female can lay up to 100 eggs. See Facts about Spotted Lanternfly for more information,