Oak tree insects - Ask Extension
I have two oak saplings about 5 or 6 feet tall. They are infested with small black insects with spotted backs that look like large ticks. They are e...
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Oak tree insects #872044
Asked June 07, 2024, 11:37 AM EDT
I have two oak saplings about 5 or 6 feet tall. They are infested with small black insects with spotted backs that look like large ticks. They are eating the leaves on my trees. Please identify these bugs and tell me how to treat my trees.
Baltimore County Maryland
Expert Response
The insects pictured are Spotted Lanternfly nymphs (juveniles), and we have seen other submissions from your county and surrounding areas with similar population levels. The insect has been in Maryland for several years now, with populations highest in your corner of the state. You can learn more about the insect on the page linked above. Treatment is not needed and they will not harm the tree.
Lanternfly can only suck plant sap with a straw-like mouth; they are incapable of chewing because they don't have jaws, so if leaf holes or tears are appearing, another organism responsible. Oaks are very valuable to local wildlife and a wide variety of caterpillars and other insects can chew their leaves, which in turn make great bird food as they hunt for insects to feed their nestlings. Because of that, use of an insecticide is not encouraged, and rarely would it be needed. There is no insecticide specific to lanternfly; anything used has the potential to harm beneficial insects as well.
A tree as young as yours is easier to see leaf damage on, but even old trees have lots of leaf injury and suffer no harmful consequences. You can share photos with us of any concerning leaf damage and we will try to determine what was responsible based on how it looks, but sometimes it's hard to tell since chewing damage can look alike when the culprit isn't visible. Beetles, for example, often feed at night and hide elsewhere during the day, and many caterpillars are well-camouflaged (or their chewing damage is older and the insect was already eaten by a bird by the time the holes were noticed).
Fortunately, trees, even when young, can afford to lose some leaf tissue to insects, storms, and disease, and usually recover just fine without intervention. Keep an eye on its watering needs as we move into drier weather patterns, but we expect it will be fine, which we can help confirm once we see photos.
Miri
Lanternfly can only suck plant sap with a straw-like mouth; they are incapable of chewing because they don't have jaws, so if leaf holes or tears are appearing, another organism responsible. Oaks are very valuable to local wildlife and a wide variety of caterpillars and other insects can chew their leaves, which in turn make great bird food as they hunt for insects to feed their nestlings. Because of that, use of an insecticide is not encouraged, and rarely would it be needed. There is no insecticide specific to lanternfly; anything used has the potential to harm beneficial insects as well.
A tree as young as yours is easier to see leaf damage on, but even old trees have lots of leaf injury and suffer no harmful consequences. You can share photos with us of any concerning leaf damage and we will try to determine what was responsible based on how it looks, but sometimes it's hard to tell since chewing damage can look alike when the culprit isn't visible. Beetles, for example, often feed at night and hide elsewhere during the day, and many caterpillars are well-camouflaged (or their chewing damage is older and the insect was already eaten by a bird by the time the holes were noticed).
Fortunately, trees, even when young, can afford to lose some leaf tissue to insects, storms, and disease, and usually recover just fine without intervention. Keep an eye on its watering needs as we move into drier weather patterns, but we expect it will be fine, which we can help confirm once we see photos.
Miri
