Lygus Bugs
Pest Common Name
- Lygus bug, Tarnished plant bug (Lygus hesperus, L. lineolaris, others)
- Crops: alfalfa, canola and other seed crops
- Vegetables and fruit: legumes, potato, tomato, carrot, berries, lettuce and others
- Weeds: chickweed, redroot pigweed dock, fleabane, goldenrod, vetch and others
Adult lygus are about 1/5 inch (6 mm) in length, and can range in color from pale green, to brown or black. Adults have yellow, black and red markings, with a distinctive yellow or green “V” on the upper center of the back. Lygus adults can sometimes be mistaken for other plant bugs and the beneficial big-eyed bug, but their characteristic markings and the clear, membranous ends of the wings of lygus can help distinguish them.
Nymphs are similar to adults in shape but are slightly more rounded and smaller. In fact, nymphs are often small enough to be mistaken for aphids but can be distinguished by their lack of cornicles (narrow, backward facing tubs found on the abdomen of aphids), and more rapid movements. Nymphs also have five black dots on the back and lack the wings of the adult form (Figure 1).
Lygus bug eggs are individually inserted into plant tissues or at the base of leaf blades. They are whiteish, slightly curved, and develop a flattened top when nymphs emerge.
