A method, comprising: planning , with a computer, a flight path for an unmanned aerial system comprising an imaging system ; operating the unmanned aerial system; collecting , with the unmanned aerial system , aerial imagery of a subject area; receiving , at the computer, the aerial imagery collected by the unmanned aerial system ; producing , at the computer, a first feature data set by analyzing the aerial imagery photogrammetrically; combining the first feature data set with a second feature data set to produce a combined feature data set, the second feature data set comprising data about a portion of the subject area that is obscured from overhead views of the imaging system of the unmanned aerial system said second feature data set being collected by one or more terrestrial survey instruments generating , at the computer, a land survey of at least a portion of the subject area, based at least in part on the combined feature data set; wherein combining the first feature data set with a second feature data set comprises: identifying one or more tie points in the second feature data set, each of the one or more tie points having a known position in a reference coordinate system; identifying a pixel coordinate, in the aerial imagery, of each of the one or more tie points; and correlating each pixel coordinate of one of the tie points in the aerial imagery with a corresponding known position on the reference coordinate system; and orienting the aerial imagery based on the correlated pixel coordinate of each of the one or more tie points. planning , with a computer, a flight path for an unmanned aerial system comprising an imaging system ; operating the unmanned aerial system; collecting , with the unmanned aerial system , aerial imagery of a subject area; receiving , at the computer, the aerial imagery collected by the unmanned aerial system ; producing , at the computer, a first feature data set by analyzing the aerial imagery photogrammetrically; combining the first feature data set with a second feature data set to produce a combined feature data set, the second feature data set comprising data about a portion of the subject area that is obscured from overhead views of the imaging system of the unmanned aerial system said second feature data set being collected by one or more terrestrial survey instruments generating , at the computer, a land survey of at least a portion of the subject area, based at least in part on the combined feature data set; wherein combining the first feature data set with a second feature data set comprises: identifying one or more tie points in the second feature data set, each of the one or more tie points having a known position in a reference coordinate system; identifying a pixel coordinate, in the aerial imagery, of each of the one or more tie points; and correlating each pixel coordinate of one of the tie points in the aerial imagery with a corresponding known position on the reference coordinate system; and orienting the aerial imagery based on the correlated pixel coordinate of each of the one or more tie points. identifying one or more tie points in the second feature data set, each of the one or more tie points having a known position in a reference coordinate system; identifying a pixel coordinate, in the aerial imagery, of each of the one or more tie points; and correlating each pixel coordinate of one of the tie points in the aerial imagery with a corresponding known position on the reference coordinate system; and orienting the aerial imagery based on the correlated pixel coordinate of each of the one or more tie points. <EOS>