Black rats ( Rattus rattus) cause extensive damage in Hawaiian macadamia ( Macadamia integrifolia) orchards. Many growers apply rodenticides to reduce rat populations in orchards, but improper placement of bait may reduce the effectiveness of many baiting programs. We evaluated the optimum placement of bait in macadamia orchards among the three locations specified on current rodenticide labels. We placed a non-toxic oat bait treated with 0.75% tetracycline hydrochloride, an antibiotic that chelates with calcium in growing bones and teeth and fluoresces under UV light, in burrows, on the ground and in trees in separate orchard sections. We consistently captured the greatest percentage of marked rats (53–91%) in sections where we placed the bait in trees and the lowest percentage of marked rats (0–36%) where we broadcast bait on the ground. Placement of bait in burrows produced intermediate results (40–70%). These results suggest that broadcasting bait on the orchard floor reduces the effectiveness of rat control programs. Placing baits in trees targets rats that not only are most likely to eat the poison bait, but also are most likely to damage developing nuts.