Methods, apparatuses, and computer program products for collective operation management in a parallel computer are provided. Embodiments include a parallel computer having a first compute node operatively coupled for data communications over a tree data communications network with a plurality of child compute nodes. Embodiments also include each child compute node performing a first collective operation. The first compute rode, for each child compute node, receives from the child compute node, a result of the first collective operation performed by the child compute node. For each result received from a child compute node, the first compute node stores a timestamp indicating a time that the child compute node completed the first collective operation. The first compute node also manages, based on the stored timestamps, execution of a second collective operation over the tree data communications network.