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Dairy manure contains an appreciable amount of NH3‐N, and if left exposed on the soil surface, it is easily lost by ammonia volatilization. Two methods of row applied liquid manure were made on corn (Zea maysL.) during the early stages of the growing season to identify the yield response to NH3conservation. From 1975 to 1977, the manure treatments consisted of a control, topdressing, and soil injection as a side‐dress application. The control received side‐dressed fertilizer N at 0 and 112 kg/ha. In 1978, rates of side‐dressed fertilizer N (0, 56, 112, and 224 kg/ha) were superimposed on the control and topdressed manure treatments to further quantify the fertilizer N equivalent of the two methods of manure application. The soil was a Minoa fine sandy loam (Aquic Duptric Eutrochrept, coarse loamy, mixed, mesic). The use of manure significantly increased yield in comparison to no manure. There was a positive response to NH3conservation in 2 out of 4 years. Atypical weather patterns in 1975 and 1976 erased the influence of the method of manure application. Grain and silage yields were significantly increased in 1977 by 1.60 and 1.88 metric tons/ha, respectively for injected vs. top‐dressed manure. Yields from manure injected plots were equivalent to the control receiving 112 kg/ha of fertilizer N. The greatest response to NH3conservation occurred in 1978. The yield advantages of injection vs. topdressing was 1.92 and 2.82 metric tons/ha for grain and silage, respectively. The data showed that in terms of yield, a 40 metric tons/ha application of manure had a fertilizer N equivalent of 30 and 90 kg N/ha (0.78 kg N/metric ton and 2.3 kg N/metric ton) for top‐dressed and injected manure, respectively.