Cerambycid beetles are abundant and diverse in forests, but much about their host relationships and adult behavior remains unknown. Generic blends of synthetic pheromones were used as lures in traps, to assess the species richness, and phenology of cerambycids in forest fragments in northern Delaware. More than 15,000 cerambycid beetles of 69 species were trapped over 2yr. Activity periods were similar to those found in previous studies, but many species were active 1–3 wk earlier in 2012 than in 2013, probably owing to warmer spring temperatures that year. In 2012, the blends were tested with and without ethanol, a host plant volatile produced by stressed trees. Of cerambycid species trapped in sufficient numbers for statistical analysis, ethanol synergized pheromone trap catches for seven species, but had no effect on attraction to pheromone for six species. One species was attracted only by ethanol. The generic pheromone blend, especially when combined with ethanol, was an effective tool for assessing the species richness and adult phenology of many cerambycid species, including nocturnal, crepuscular, and cryptic species that are otherwise difficult to find.