Row spacing studies were conducted in Georgia comparing 30" and 36" at plains and Tifton and 30" and 38" at Athens. Tests were conducted at Plains for five years and Tifton and Athens for 2 years. These location represent growing conditions and soil types in the cotton producing areas in the state. Entries were selected to represent a range of plant types from vigorous to semi-determinate or short season types.

DPL 90, Coker 208, McNair 220 and Ga 146 were planted at Plains for three years and Tifcot 56 and Stoneville 506 were include for two years. The 30" row significantly different. The three year average yield for the four varieties was 6% higher for the six varieties. There were significant variety differences within row spacings, but there was no significant variety x row spacing interaction.

In 1990 tests were planted at Athens Plains and Tifton with five entries at Plains and Athens and six at Tifton.DPL 90 and Tifcot 56 represented vigorous types and semi-determined or short season types were Ga 342, Ga 348, Ga 31 and Ga 256. There were variety differences within row spacings. There were no differences due to row spacing nor was there a significant variety x row spacing interaction. The 30" rows resulted in a yield reduction of 8, 3, and 5 percent at Plains, Tifton and Athens, respectively.

Tests were planted at Athens, Plains and Tifton again in 1991 with a change in varieties. DPL 77, DPL 90, Ga 256, Ga 342, Georgia King and Tifcot 56 were planted at Athens and Tifton and DES 119 was included at Plains. There was no significant difference to due row spacing at Athens and Tifton. The 30" rows were significantly better at Plains with an 8% increase. There were differences between varieties within row spacing, but there was no significant variety x row spacing interaction at any location.

Row spacing did not significantly influence lint percent, boll size or fiber properties.

These data show a range of plant types performed equally in 30, 36 and 38 inch rows.