Coloured Sticky Traps: Yellow sticky traps are a common method for monitoring many pests, including aphids, whiteflies, and leafminer adults. Use of yellow sticky traps in seedling production areas at the rate of 2 traps / 100 square meters can trap significant numbers of whiteflies. It is observed that yellow sticky traps significantly suppress the population increase of adult and immature whiteflies in greenhouses. Similarly, thrips are highly attracted to bright blue colour; blue sticky traps can be set up every 3 square meter in a greenhouse for effective control. Sticky yellow rectangle traps have been used for many years to capture fruit flies. Traditional sticky yellow traps are coated with a sticky gel that can leave residues on the hands of users. An alternative to this is hot melt pressure sensitive adhesives (HMPSAs), which are not messy. Trasy Enterprises, India, make machine which coat HMPSA on cards and cuts and punches the material to convert it to sticky traps.