Survival, emergence, and branch girdling by Oncideres pustulata LeConte on huisache, Acacia farnesiana (L.) Willd., and leucaena, Leucaena leucocephala (Lam.) de Wit, the preferred host plants, were compared in field studies in northeastern Mexico during 2003–2005. Most mortality of medium- to large-sized larvae was attributed to predation by birds, while small larvae were killed by cold temperatures (<4 °C) during the winter of 2004. Birds observed preying upon O. pustulata were the bronzed cowbird, Molothrus aeneus (Wagler), and red-winged blackbird, Agelaius phoeniceus L. Predation by birds was two to three times greater on leucaena than huisache, probably because of the softer wood of leucaena. Consequently, emergence of adults from huisache was 50–80% greater than from leucaena. The relationship between cumulative emergence rate and time was sigmoidal (r² = 0.99), with 50% emerging during early October, irrespective of host plant or year. The sex ratio of emerging adults throughout the study was skewed toward females (1.6:1) regardless of host plant or year. The relationship between cumulative rates of branch girdling and time was also sigmoidal (r² ≥ 0.98) with no significant difference between host plants. The number of branches girdled per tree ranged from 4.6 in 2003 to 0.1 in 2005 as a consequence of the impact of subfreezing temperatures during the previous winter. Although the number of branches girdled by O. pustulata was similar in both host plants, the average diameter of girdled twigs was significantly greater in leucaena (2.8 cm) than huisache (2.2 cm), probably because of the softer wood of leucaena. O. pustulata successfully utilized both huisache and leucaena as host plants. However, our results suggested that more O. pustulata survived and emerged on huisache. This probably is because of less predation by birds on larvae in huisache because of its harder wood, as compared to leucaena.