Injury

Spotted lanternfly feeds on a wide range of woody plants, including fruit trees, grapevines, hops, shade trees, and ornamental shrubs. More than 70 plant species are known hosts. Both adults and immature stages feed by tapping into the plant’s internal tissues, usually on trunks and stems, and produce a sugary waste called honeydew.

Honeydew can build up on leaves and nearby surfaces, attracting insects such as ants, bees, flies, and wasps. It also encourages the growth of black sooty mold. This buildup can interfere with plant health and create sticky messes on outdoor surfaces like cars, decks, and patio furniture.

Heavy infestations can put significant stress on plants, leading to reduced growth, wilting, dieback, and in some cases plant death. Spotted lanternfly often gathers in large numbers, with hundreds or even thousands of insects feeding on a single tree, which increases both plant damage and nuisance problems in residential and commercial areas.

Grapevines and hops are especially vulnerable, and serious impacts to these crops have been seen in areas where this pest is established. If spotted lanternfly becomes established in Colorado, it could affect specialty crop production as well as urban and ornamental landscapes.

Monitoring

Check yards, landscaped areas, and nearby natural areas for spotted lanternfly from July through November, especially where tree-of-heaven is growing. Although this insect has not been found in Colorado, early detection is important to prevent it from becoming established.

What to look for

Look for all life stages of spotted lanternfly:

• Egg masses (fall through spring)
• Nymphs (spring through early summer)
• Adults (mid-summer through fall)

Tree-of-heaven is a favorite host plant and a good place to focus your search.

Monitoring methods

• Visual checks: look closely at tree trunks, stems, and nearby surfaces for insects or egg masses.
• Sticky bands: wrap sticky bands around tree trunks to catch young insects as they move up and down the tree.
• Circle traps: these funnel-style traps can be placed on tree trunks to help detect both nymph and adult insects.

For best results, place traps about one meter above the ground.

Checking traps

Check traps every 1-2 weeks so that insects can be clearly identified. Waiting too long can cause specimens to break down, making them harder to recognize. Some traps may collect rainwater, which can speed up this process and create unpleasant odors.

Report suspected sightings

If you think you have found spotted lanternfly:

• Take clear photos of the insect or egg mass.
• Note the location with an address or GPS coordinates.
• Report the sighting, with the photos and location, to your local CSU Extension office or the Colorado Department of Agriculture.

Reporting possible sightings helps protect Colorado by allowing experts to respond quickly.

Management

Accurate identification is critical. If you suspect spotted lanternfly, report the sighting before considering treatment. This supports early detection efforts in Colorado. Chemical controls should be used responsibly and in accordance with label instructions as part of an integrated approach. The insecticide information provided here is based on research conducted in eastern states where spotted lanternfly populations are established. 

Non-chemical management approaches include removal of attractive host plants (such as tree-of-heaven, grapes, wild vines, and certain weedy species) and the mechanical destruction of egg masses.

Given its status as a highly destructive emerging pest, research on the chemical management of spotted lanternfly is ongoing. Current efforts are focused on identifying insecticides that are effective against different life stages and provide lasting control under field conditions. Studies to date show that several commonly used insecticides can provide strong initial knockdown of nymphs and adults. These include pyrethroids, neonicotinoids, carbamates, and organophosphates. However, fewer products offer extended residual control. Among the materials evaluated, thiamethoxam and bifenthrin have demonstrated some of the most consistent residual activity, with control of adult spotted lanternfly lasting up to approximately two weeks after application. Dinotefuran has also shown high effectiveness shortly after exposure, particularly against mobile life stages.

For egg masses, the most effective material evaluated in some studies has been the organophosphate chlorpyrifos, which achieved complete egg mortality under experimental conditions, while horticultural oils provided only partial suppression. Organic (OMRI-listed) products tested to date have shown limited effectiveness, suggesting that management in organic systems may be more challenging.

Despite the availability of effective insecticides, management of spotted lanternfly can be difficult due to its wide host range and tendency to move among plants. Treating individual trees is often insufficient when populations are high or widely distributed. For this reason, insecticide use is typically most effective when combined with other strategies such as host plant removal, monitoring, and targeting insecticide applications to vulnerable life stages. Area-wide approaches, including the use of biological control agents such as Beauveria bassiana, have shown some promise in reducing local populations, but these methods are still being evaluated.

References