The relationship between caste polymorphism and foraging strategy was examined in the Florida harvester ant,Pogonomyrmex badius(Latreille). Foragers ofP. badiuswere offered two sizes of barley seed (4 or 33 mg) at 1, 2, 5, and 10 m from the nest entrance. No consistently significant correlations were found between forager size and the size of seed collected. Distance of seed from the nest was not associated with worker size or seed selection. In this species, it does not appear that polymorphism can be explained by simple models of foraging optimization through the pairing of worker size and seed size.