Evaluation of Wheat Planted on 15‐Inch Row Spacing in Eastern Kansas

Producers in eastern Kansas are beginning to use planters with 15‐inch row spacing to plant hard red winter wheat (Triticum aestivum L.) vs. traditional 7‐ to 10‐inch drill equipment. The objectives of this study were to evaluate weed emergence and wheat yield effects when sowing wheat with a 15‐inch row planter vs. 7.5‐inch row drill equipment at a seeding rate of 1.0 and 1.2 million seeds/acre. The experiments were duplicated each year, one with an herbicide application and one without herbicide. Henbit (Lamium amplexicaule L.), Carolina foxtail (Alopecurus carolinianus Walt.), smallflowered bittercress (Cardamine parviflora L.), and common chickweed [Stellaria media (L.) Vill.] emergence was greater in the 15‐inch planter rows vs. the 7.5‐inch drill rows. Wheat sown in the 15‐inch planter rows in the herbicide‐treated experiment yielded 17.4 bu/acre less than wheat sown with the 7.5‐inch drill rows. Wheat sown with the 15‐inch planter in the untreated herbicide experiment yielded 15.1 bu/acre less than wheat sown with the 7.5‐inch drill. Yield losses for wheat in 15‐inch planter rows in both experiments are attributed to too wide of a row spacing to maximize yields.