Subject: Bug on sunflowers
Location: Southern Nevada
May 19, 2013 10:19 pm
I have a bunch of these bugs showing up on my sunflowers in my garden. I live in Boulder City Nevada, which sits right on the border of Arizona and Nevada, about 30 miles south of Las Vegas. They appeared about a week ago, so the middle of May. I just want to know if they are harmful, helpful or neutral to my garden.
Your sunflower has Lace Bugs in the family Tingidae. Lace Bugs are True Bugs and they do not bite nor chew leaves, but rather they use their piercing and sucking mouthparts to draw nourishment from the plant fluids. Normally we don’t attempt to identify Lace Bugs to the species level, and your photo is lacking in the type of essential detail for such an identification, however, since you provided a food plant, we gave it a shot and we believe you have Chrysanthemum Lace Bugs, Corythucha marmorata, which according to BugGuide commenter L. T. Miller are: “Common in many composite flowers.” According to the University of Illinois College of Agricultural, Consumer and Environmental Sciences (ACES) website: “Chrysanthemum lace bugs feed on asters, sunflowers, and goldenrods, injuring the plant by their piercing and sucking. The excrement is strategically placed along the vein and secures the eggs to the leaf. They prefer the underside of the leaf but will also colonize the upper side when the population is high. Nymphs are small and shiny brown, and they suck sap. Young nymphs congregate on the underside of the leaves. In dry weather, high populations can cause particularly severe damage. Hover-fly larvae, lady beetles, and lace-wing larvae will prey on these garden pests. Daily water sprays can be highly effective at reducing the population. U of I Extension suggests treating plants with horticulture oil, insecticidal soap, neem oil, or imidacloprid.”