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Hawaii ranchers identified reducing input costs as a priority for research and education. Cost of ranch inputs such as herbicides are high owing to lengthy transportation distance to Hawaii. Incorporating different types of livestock in a grazing system to exploit inherent differences in their foraging behavior has successfully replaced herbicides for managing certain weeds. Despite these successes, some plants remain problematic as livestock avoid them altogether or do not eat enough to check their increase in pasture. A promising method developed on the U.S. mainland to train livestock to eat unfamiliar plants, still under development, has not been systematically pilot-tested and demonstrated across pasture types in the tropics. By experience and in consultation with collaborating ranchers, we identified the following species as weeds to target: Asclepias physocarpa, Elephantopus mollis, Leonotis nepetifolia, Schizachyrium condensatum, and Sphagneticola trilobata. The training attempts to create positive associations with unfamiliar feeds with the goal of increasing intake of target weeds. Over the course of 5-7 days, twice daily we offered small amounts of unfamiliar but high quality feeds such as corn, oats, timothy hay, and others to cattle, sheep, and goats that had lived entirely on pasture. On the last two days of training, the morning feedings were skipped to increase interest and the target weeds were introduced. While the preference conditioning was successful for all target plants except A. physocarpa in that animals initially ate them to various degrees, pasture monitoring did not reveal trends in overall weed control. One exception was a notable reduction of E. mollis in sheep grazed pasture. This pilot study indicates that conditioned preference training holds potential for some tropical weeds, but that further steps such as increasing animal density or attenuating plant toxins with supplements may be necessary to augment this approach for better control.