How do people plan ahead when searching for rewards? Weinvestigate planning in a foraging task in which participantssearch for rewards on an infinite two-dimensional grid. Ourresults show that their search is best-described by a modelwhich searches at least 3 steps ahead. Furthermore, partici-pants do not seem to update their beliefs during planning, butrather treat their initial beliefs as given, a strategy similar to aheuristic called root-sampling. This planning algorithm corre-sponds well with participants’ behavior in test problems withrestricted movement and varying degrees of information, out-performing more complex models. These results enrich ourunderstanding of adaptive planning in complex environments