ABSTRACT: Female Oncideres pustulatus LeConte girdle Acacia farnesiana (L.) Willd. branches to provide a suitable host for their progeny. After girdling a branch, eggs are laid in the girdled section where the hatching larvae feed beneath the bark. Girdled branches were 13-55 mm in diameter and up to 4.01 m in length. Females contained as many as 63 mature eggs, but oviposition averaged 312 eggs per branch; a maximum of 2,898 eggs was laid on a single branch. A multiple regression analysis indicated that branch volume, number variation in egg numbers per branch (r2, 0.806). Larvae consumed an average of 9.3 cm of wood from the girdled branches, but high oviposition densities within a branch forces larvae to compete for the limited resource. When one female begins girdling a branch, other females oviposit on the branch without assisting in the girdling. Potential reproductive strategies by girdling and nongirdling females are discussed.