Back to top

Odontota dorsalis

Locust leafminer egg, larva, pupa, and adult. Photo: Bruce W. Kauffman, Tennessee Department of Agriculture, Bugwood.
Scientific Name: 
Odontota dorsalis
Common Name: 
Locust Leafminer
Growing Degree Days (GDD's): 
298–533 GDD's; again 1029–1388 GDD's, Base 50F, March 1st Start Date (Source: Cornell Cooperative Extension; Robert Childs, UMass Extension.)
Host Plant(s) Common Name (Scientific Name): 
Apple (Malus spp.)
Beech (Fagus spp.) *Adult food.
Birch (Betula spp.)
Black locust (Robinia pseudoacacia) *Preferred hosts of larvae and adults.
Bristly locust (Robinia hispida) *Larval food.
Cherry (Prunus spp.) *Adult food.
Dogwood (Cornus spp.) *Adult food.
Elm (Ulmus spp.) *Adult food.
Golden chain tree (Laburnum anagyroides) *Larval food.
Hawthorn (Crataegus spp.) *Adult food.
Japanese pagoda tree (Styphnolobium japonicum) *Larval food.
Oak (Quercus spp.) *Adult food.
Wisteria (Wisteria spp.) *Adult food.
Insect Description: 

Adult locust leafminers are beetles that are approximately 6 mm long. Adult beetles are the overwintering life stage, often found sheltered beneath the leaf litter nearby host trees. When temperatures warm in the spring, adult beetles emerge from their winter locations and begin feeding on newly developing host plant leaves. Adult females deposit their eggs which are flat and oval in shape on the underside of host plant leaves. Eggs overlap and are cemented together with excrement. Following hatch, the larvae enter the tissues between the top and bottom layer of the leaf, creating a mine as they feed. Mines grow in size as the larvae grow in size and feed. This species preferentially mines the tips of host plant leaflets. Mines are irregular blotches in shape, containing larvae that when fully grown appear flattened and yellowish-white in color. Larvae have black heads, legs, and a black anal shield. Pupation occurs within the mines in the host plant leaves. Beetles will emerge from the pupal cases, at which point the adult beetles will skeletonize the undersides of the host plant leaves. In parts of its range, such as southern Ohio, a second generation of locust leafminers occurs. A second species of leafmining insect (Sumitrosis rosea) occurs in locust and may be found in the same trees as Odontota dorsalis

Damage to Host: 

Foliage of black locust are impacted by the larvae and adult beetles. Larvae create a blotch-shaped leaf mine. Adults will skeletonize the undersides of the host plant leaflets. In high populations the entire tree's foliage can appear fire-swept by late summer. If a tree grows two sets of leaves during a single season, the locust leafminer is capable of damaging both. If this happens during multiple seasons, the tree will perish. 


Monitor for adult beetle emergence as new foliage develops in the spring. Flip leaves over and search for egg masses. Damage from this insect may not be noticed until leaves appear scorched or browned by mid-summer.

Cultural Management: 

Proper planting and practices that maintain tree vigor can help individual trees withstand defoliation if it occurs. This can include adequate watering during drought periods. 

Natural Enemies & Biological Control: 

Several wasp parasitoids of the locust leafminer are reported. Trichogramma odontotae, Spilochalcis odontotae, and Closterocerus tricinctus are three notable species. In the southern portion of the locust leafminer's range, the wheel bug Arilus cristatus is a common predator of the larvae while they are still inside the leaf tissue. Another predator in the Miridae, Lopidea robinae is also known. 

Chemical Management: 

Abamectin (NL)

Acephate (NL)

Azadirachtin (NL)

Beauveria bassiana (NL)

Bifenthrin (NL)

Clothianidin (NL)

Cyantraniliprole (NL)

Diflubenzuron (N)

Dinotefuran (NL)

Emamectin benzoate (L)

Fenpropathrin (NL)

Flonicamid+cyclaniliprole (N)

Gamma-cyhalothrin (adults) (L)

Horticultural oil (L)

Imidacloprid (L)

Insecticidal soap (NL)

Lambda-cyhalothrin (adults) (L)


Neem oil (NL)

Permethrin (L)

Pyrethrin+sulfur (NL)

Spinosad (NL)


Active ingredients that may be applied systemically include: Abamectin (injection), acephate (injection), acetamiprid (injection), azadirachtin (injection, soil drench), clothianidin (soil drench), cyantraniliprole (soil drench, soil injection), diflubenzuron (soil drench), dinotefuran (soil drench), emamectin benzoate (injection), imidacloprid (soil drench), and neem oil (soil drench).

Make insecticide applications after bloom to protect pollinators. Applications at times of the day and temperatures when pollinators are less likely to be active can also reduce the risk of impacting their populations.

Note: Beginning July 1, 2022, neonicotinoid insecticides are classified as state restricted use for use on tree and shrub insect pests in Massachusetts. For more information, visit the MA Department of Agricultural Resources Pesticide Program.

Read and follow all label instructions for safety and proper use. If this guide contradicts language on the label, follow the most up-to-date instructions on the product label. Always confirm that the site you wish to treat and the pest you wish to manage are on the label before using any pesticide. Read the full disclaimer. Active ingredients labeled "L" indicate some products containing the active ingredient are labeled for landscape uses on trees or shrubs. Active ingredients labeled "N" indicate some products containing the active ingredient are labeled for use in nurseries. Always confirm allowable uses on product labels. This active ingredient list is based on what was registered for use in Massachusetts at the time of publication. This information changes rapidly and may not be up to date. If you are viewing this information from another state, check with your local Extension Service and State Pesticide Program for local uses and regulations. Active ingredient lists were last updated: January 2024. To check current product registrations in Massachusetts, please visit: .