There is a lure but Spectracide is pretty vague about what is actually in the lure, probably to keep people from reproducing the lure. This is from the Spectracide website. www.spectracide.com/products/insect-killers/japanese-beetle-control/spectracide-bag-a-bug-japanese-beetle-trap2-replacement-lure.aspx "Spectracide® Bag-A-Bug® Japanese Beetle Trap2 Replacement Lure is designed to be used with Spectracide Bag-A-Bug Japanese Beetle Trap2 (sold separately). The dual lure draws Japanese beetles away from valuable ornamentals, flowers and shrubs, helping to protect roses, grapes, fruit trees and vegetables. This lure contains natural pheromones, together with a proven floral lure, to attract two to five times as many beetles as the commonly available floral lure alone. Under normal conditions, one lure is effective for about 12 weeks; replace it after this period or when its floral aroma is no longer noticeable."
