A network device stores in its nonvolatile memory, in response to detecting a power outage in a tree-based network, an identifier for a preferred parent and a distance identifier for the network device within the network. In response to power restoration, the network device starts a trickle timer based on the ring identifier, for determining whether a beacon request from a transmitting node and destined for the preferred parent is detected during the waiting interval. In response to the network device detecting the beacon request during the waiting interval, the network device sets its channel hopping schedule to the corresponding channel hopping schedule of the transmitting node in response to determining the beacon request is destined for the preferred parent, enabling rejoining with the preferred parent in response to detecting a beacon from the preferred parent to the transmitting node via the corresponding channel hopping schedule of the transmitting node.