Abstract: Management of corn (Zea mays) row spacings and populations has been used for many years to increase corn productivity. In 1998 and 1999, nonirrigated corn was grown in 38-, 56-, and 76-cm row spacings at populations averaging 59,300, 72,900, and 83,900 plants/ha in Michigan. Glufosinate at 0.29 kg/ha was applied to common lambsquarters (Chenopodium album L.) averaging 5 cm in height in each plot. Corn population and row spacing did not influence weed emergence following application of glufosinate. Common lambsquarters biomass and seed production were reduced when grown under canopies of corn planted in populations exceeding 72,900 plants/ha. Common lambsquarters biomass was reduced as corn row spacings were reduced from 76 to 38 cm. Early-season interception of photosynthetic active radiation (PAR) by corn canopies increased as row spacings decreased, but differences were not apparent later in the season. Interception of PAR was similar throughout the season when corn populations exceeded 72,900 plants/ha. Corn yields were not affected by row spacing, but they were increased with corn populations of 72,900 plants/ha or higher.
Nomenclature: Glufosinate; common lambsquarters, Chenopodium album L,. #3 CHEAL; corn, Zea mays L. ‘DK 493GR’.
Additional index words: Crop density, herbicide-tolerant crops, narrow-row corn.
Abbreviation: PAR, photosynthetic active radiation.