What are Poplar Weevils?
Poplar weevils are small, black-brown weevils that reach about 3/16 inch (5 mm.) long. Like other weevils, they have long snouts, but because of their small size, you may not notice that or the deep groove in their wing covers. Many people simply identify them as “flying fleas” due to their size and shape. Yellow poplar weevil damage is distinctive, often appearing as holes in leaves or buds the same size and shape as a curved grain of rice. Sadly, that’s not where yellow poplar weevil damage ends. Their offspring are leaf miners that burrow into the leaf tissue and create blotch mines between the layers. On the outside of the leaf, this appears as a large brown spot that starts on a leaf margin. As these tiny pests feed, they grow and then pupate inside the mine. Adults emerge in June or July to start the cycle over again.
Managing Yellow Poplar Weevils
Unless your tulip tree is very young or your weevil problem severe, there’s no reason to attempt yellow poplar weevil control. The damage they cause to established trees is strictly ornamental and successfully killing them requires a great deal of patience and precision. Since these weevils spend the majority of their lives inside the leaf tissue, you can’t simply spray the surfaces in hopes that the poison will seep through. Successful yellow poplar weevil control comes down to timing. If you wait until about 10 percent of the branches of your tree show damage, you may be able to kill off the majority of the adults feeding on your tree with acephate, carbaryl, or chlorpyrifos. However, poison your weevils with caution, since you’ll also kill the natural enemies that would have destroyed many of them without your intervention.
