The United States, Europe and China are growing “sentinel trees” in strategic locations around the world to receive advance warnings of destructive pests that could destroy native plantings. According to a study published in Plos One, “Sentinel nurseries represent one potential mechanism to address the current lack of knowledge about pests in the countries from where live plants are shipped and the threats they represent to native flora and crops in importing countries.” As global trade intensifies, the risk for accidental importing of and exposure to new invasive pests is a constant worry for entomologists and arborists, stimulating a search for new tactics to prevent future losses.