by Tina Graver
The first signs of the Eastern Tent Caterpillar emerged just last week: small, silk webs in the branch unions of their favorite tree, the black cherry. The silk webs provide a safe place for the caterpillars to hide in the night and digest all of the cherry leaves they have consumed during the day. Over the next month, the caterpillars will diligently feed, sometimes to the point that the host tree is completely defoliated. On a usual year, the cherry trees are able to fully recover from an early defoliation. However, every ten years the Eastern Tent Caterpillar has a heavy population outbreak and will move to other trees such as Peach, plum, witch hazel, beech, birch, willow and poplar. During these outbreaks, these other trees may become weakened or killed.
Now is the time to call your certified arborist if you have any of this caterpillars favorite trees. The earlier an arborist can intervene, the sooner leaf loss can be intercepted. Cultural control includes simply pruning out the tent or by ripping out the tent. The market has several organic chemical control options available to licensed commercial applicators. The sooner in the insects’ life-cycle that the application is made, the greater the chance of control and the lesser the chance of needing to return with a stronger pesticide. At Mead Tree & Turf Care, we prioritize early intervention and use the recommendations of the Maryland Extension Service to carefully time our chemical applications.
For clients that are new to the area, and are not used to dealing with this pest, May can be an alarming time. Once the large, mature caterpillars are finished feeding, they migrate downward, out of the trees. At this time, they can swarm yards, porches and even cars as they search for a place to pupate into a light-brown colored moth. Unfortunately, this really isn’t the time to try and control this caterpillar. Calling an Arborist at this time, however, can ensure an early intervention during the next growing season.