Box Tree Moth Wreaks Havoc on Metro Detroit Boxwood Shrubs
Homeowners in Metro Detroit are being warned about the growing threats to their boxwood shrubs. Boxwoods are one of the most common plants found in yards throughout the region, but they're facing a number of challenges including diseases, pests, harsh weather, and a newer invasive pest that can cause rapid damage.
According to Chris Ellison, a garden pharmacist with English Gardens, boxwoods are abundant in neighborhoods around Metro Detroit. However, many homeowners have noticed their once-green boxwoods turning brown due to various factors such as harsh winters, droughts, diseases like boxwood blight, and pests including the boxwood psyllids, spider mites, and the boxwood leafminer.
A newer threat to boxwoods is the box tree moth, which exclusively feeds on boxwoods. The pest is native to East Asia and arrived in Michigan in 2022. It does its most damage in its caterpillar stage and is currently under quarantine in 13 counties in the southeastern portion of the state.
Experts say early detection is critical to protecting boxwoods from the moth, which can cause rapid defoliation. Ellison recommends spraying an organic insecticide known as BT to kill the pest, and using the right fertilizer to promote new growth in affected shrubs.