Synopsis: Six corn hybrids tolerant and 5 hybrids intolerant of high populations were tested for their response to a shade environment under conditions of adequate soil moisture and fertility. In shade, the grain yield of the tolerant hybrids as a group was significantly higher than that of the intolerant hybrids. Ear barrenness contributed more to the differential yield response of the tolerant and intolerant hybrids than did reduction in ear weight.