Studies using Oecophylla smaragdina colonies to control cashew insect pests showed that the introduction of a partial ant colony was more permanent with a reproductive queen than without a queen. Thus, a technique to locate queens was needed. The nests of twelve established O. smaragdina colonies were examined. Each comprised many nests, but only one contained queens, and it commonly had multiple queens. The tree with queen ants had (1) the most ant trails connecting it to other trees included in the colony, and (2) more nests than the other trees in the colony. The nests with queen ants were near the top of the tree canopy and were of medium-size. Using these criteria, the average success rate of finding the queen nest in a colony was 95%. The queens apparently stay in one nest from which eggs are distributed to the other nests in the colony.