This hour of Let's Garden is a fascinating conversation about plant galls, a common issue in many gardens, and the box tree moth, a non-native insect causing trouble in Ohio. The speaker is joined by Chris Stone, Director of Horticulture at Boone County Arboretum, and Brian, Director of Horticulture at Spring Grove Cemetery and Arboretum, as they delve into the world of arthropods and the impact of the box tree moth on local ecosystems.

The conversation starts with a discussion about plant galls, which are swellings on stems or leaves that can be caused by various arthropods, including wasps and mites. The speaker shares a personal anecdote about receiving an email from a gardener in Northwest Virginia who is concerned about a gall outbreak on their oak tree. Chris and Brian explain that most galls cause no harm to trees and that the speaker's email is likely a case of mistaken identity, with the tree's poor health being caused by environmental factors rather than the galls.

The conversation then shifts to the box tree moth, a non-native insect that is causing problems in Ohio. Brian shares that the moth is originally from Asia and was accidentally introduced to Europe, where it has caused significant damage to boxwood trees. The speaker notes that boxwoods are not native to North America and that the moth's presence is a concern for local ecosystems. Chris and Brian discuss the importance of monitoring for the caterpillars and using organic insecticides, such as spinosad, to control the population.