Leptocorisa oratorius(F.) adults preferredEchinochloa cruz-galli(L.) over rice,Oriza sativaL., var. IR 36, for resting sites, whereas rice was preferred overEleusine indica(L.),Echinochloa colona(L.),Brachiaria mutica(Forsk.),Paspalum conjugatumBerg.,P. paspalodesL., andDigitaria ciliaris(Retz.).L. oratoriusoviposited on all plant species, but those confined for 8 d on flowering rice laid more eggs than those confined on weeds. Females began oviposition 2 wk after molting, and fecundity was consistent for 5 wk. Nymphs completed their development only onE. cruz-galli,E. colona,D. ciliaris, or rice after panicle emergence. Results indicate that weed control is an important factor inL. oratoriusmanagement programs.