The southern chinch bug, Blissus insularis Barber, reportedly causes more damage and is more abundant in sunny, open, drought-stressed areas of St. Augustinegrass lawns. However, little is known about the response of St. Augustinegrass to B. insularis feeding and the interaction with irrigation. We sought to quantify St. Augustinegrass growth response to three levels each of irrigation (30, 60, or 100 % saturation) and B. insularis densities (0, 30, or 200 fourth and fifth instars). Grass was cut weekly to a 7.6 cm height, and clippings and root data were collected. Stunted growth from B. insularis feeding was observed from grass clippings collected after 1 wk. Dry weights of grass clippings from treatments containing 30 or 200 B. insularis were lower than treatments containing 0 B. insularis except during weeks two, six, and seven. During this time, grass clipping dry weight was lowest in treatments containing 200 B. insularis. At five weeks, grass clipping dry weight from treatments with different irrigation levels was lowest in treatments receiving low irrigation. At week seven, there was no significant difference between treatments receiving low or medium irrigation. Irrigation did not affect root growth, root weight, or interact with B. insularis density to affect plant growth. Blissus insularis feeding in densities of 30 and 200 reduced leaf blade growth and root weight. In summary, extensive B. insularis damage may look like drought stress, but not be a result thereof. Thus, increased irrigation may not help turf recover physiologically.