Abstract: The absorber plant method of geobotanical prospecting was tested systematically over the bench formed by the Jurassic Todilto limestone on the south flank of Haystack Butte, McKinley County, N. Mex. This portion of the bench includes the largest known uranium ore body in limestone and most has been extensively drilled by private enterprise. Geobotanical prospecting was accomplished to provide control data. Comparison of the geobotanical anomalies with the available drill hole information from the mining companies and Atomic Energy Commission geologists have shown that the known ore occurrences would have been outlined by the results of the tree sampling. In addition some geobotanical anomalies are indicated in drilled areas in which ore was not reported and in areas not physically explored at the time of sampling. These anomalies may represent mineralized ground below ore grade or new ore deposits.