Facts, Identification & Control
Thrips are small insects and may or may not have wings. The word thrips is always spelled with a “s” since the word is both singular and plural just like the word species is both singular and plural. Winged thrips have fringed wings; in fact, the name of the order Thysanoptera is derived from the Greek words for fringe ( thysano) and wing ( ptera). More than 5,000 species of thrips have been identified. Thrips vary in size, though most measure between 0.5 to 5 mm in length.
Thrips possess distinctive asymmetrical mouthparts with one mandible longer than the other. Some thrips use their mouthparts to puncture the outer layer of plants, from which they extract sap, while others use them to puncture the skin of animals such as other insects, from which they extract body fluids.
Behavior, Diet & Habits
Plant-feeding thrips are capable of damaging crops. After feeding on plants, thrips leave visible signs of damage such as deformities and blackening of the skin. Thrips may also lay their eggs on fruits and crops, resulting in small discolorations surrounded by white haloes. In addition to marring the appearance of flowers, these thrips can spread a number of plant diseases, such as the tomato spotted wilt virus and the necrotic spot virus.
Common plant-feeding thrips are flower thrips. These thrips are yellow, orange or amber in color. Flower thrips typically grow in population during spring.
Because their feeding habits destroy a number of commercial crops, thrips are considered especially problematic in agricultural communities. They are known to proliferate quickly and swarm heavily in areas with crops. Thrips do invade homes, possibly brought in on potted plants, and some species have been known to bite humans. If thrips populations are not controlled, affected flowering plants may lose their ability to produce.
Female thrips typically lay their eggs in or on plants. Nymphs hatch and undergo a series of molts until they become adults. Prior to becoming adults, late-stage nymphs cease feeding and a find a protected location to molt.
Signs of a Thrips Infestation
Signs depend on the species of thrips. The sightings of thrips are an indication. Plant-feeding species can cause damage to plant tissues like flower buds, fruits or vegetables.