Sunfish ponds were fertilized 11 times during the growing season with liquid ammonium polyphosphate (N-P2O3-K2O:13–38-0) at 5.6, 11.2, or 22.4 kg/hectare per application. Net production of sunfish averaged 310, 315, and 418 kg/hectare in the low, medium, and high treatments, respectively. Net production of sunfish in the high treatment differed from net sunfish production of the other treatments (P < 0.1). These findings suggest that 5.6 kg/hectare per application of liquid ammonium polyphosphate (13–38-0) is suitable fertilization for woodland ponds with low to moderate fishing. A rate of 22.4 kg/hectare per application is adequate in woodland ponds with heavy fishing. Uniform surface application was the most effective technique of applying liquid ammonium polyphosphate. Liquid ammonium polyphosphate fertilization would generally be cheaper than fertilization with conventional granular fertilizers.