Excerpt: "Sugaring" and attraction to artificial light have long been favorite methods of collecting adults of the genus Catocala, and both have been very successful. Each of the many collectors who uses the English method of applying bait to the trunks of trees has his own preferred mixture. Usually molasses is the base, and fragrance is the measure. Feed molasses is widely used in this country, augmented by various combinations of beer, rum, aromatic oils and decaying fruits. Temperature, humidity, wind and amount of moonlight are all well-known factors affecting the success of "bait," whether applied according to the old method or used in the modern variant of bait-traps. The advent of ultra-violet and mercury-vapor light has been a boon to students of this genus. According to the present low level of evidence, certain species would seem to have a preference for either bait or light. Experienced.lepidopterists insist that some species are not attracted to one or the other, but the phenomenon has not at all been carefully studied.
Wilkinson, Ronald S.
"Daylight Collecting of Catocala (Lepidoptera: Nocturidae),"
The Great Lakes Entomologist, vol 4
Available at: https://scholar.valpo.edu/tgle/vol4/iss2/6