We carry yellow sticky cards that are sticky on both sides with peel-off coverings. For monitoring, hang every 250 square feet or, to trap emerging fungus gnats, hang horizontally over pots. Yellow attracts many insects including whitefly, winged aphid, shore fly, fungus gnat, leafminer and thrips. Note counts weekly and keep records to observe trends. Blue sticky cards are also available for attracting thrips and leafminer, especially if beneficials are attracted to yellow cards. Large sticky banners also available.