Hello Gardeners, I’m Amanda McNulty with Clemson Extension and Making It Grow . All over the country, scientists check for the presence of the invasive and deadly Emerald Ash Borer by placing purple traps in trees. These devices are baited with sex pheromones that entice male beetles to enter the traps from which they can’t escape. The half-inch or so long beetles are not great flyers, they don’t move very quickly by themselves, but have spread quickly to 30 states, mostly in the Eastern half of