Effective resource advertisement and discovery (Ad/D) are particularly important in mobile ad hoc networks (MANETs), due to network dynamics and resource constraints of wireless nodes. In this paper, we propose an adaptive and scalable resource Ad/D technique for MANETs. Based on a variable zone size, it combines push-based Ad/D with a pull-based Ad/D that uses a modified bordercasting resolution protocol. The scheme avoids redundant flooding and reduces system overhead by piggybacking resource information on the routing-layer packet, and adapts locally to changing conditions, such as mobility and popularity levels, in a MANET. Simulation results verify that our scheme can track a changing network environment while reducing the resource Ad/D network overheads, thereby saving resources, decreasing latency and being scalable to large MANETs.