F E B R U A R Y 2 0 1 8 12 POTATO GROWER Controlling weeds without damag- ing potato plants is highly desirable. We are constantly evaluating prod- ucts and mixtures to best fit produc- tion practices in North Dakota and Minnesota, but these results could be used in other areas based on approved labels. The NDSU Extension Service does not endorse commercial products or companies even though reference may be made to tradenames, trademarks or serv- ice names. This study was completed in 2017 near Park Rapids, Minnesota to eval- uate the effects of Sonalan (ethalflu- ralin) tank mixtures in Russet Burbank potato production. Planting occurred on May 5, 2017 in plots measuring 12 ft wide x 25 ft long. Soil characteristics were 76% sand, 18% silt, 8% clay with 1.6% organic matter and a pH of 6.4. Treatments were applied on May 24 as a preemergence treatment with shoots approximately 3 to 4 inches below the top of the hill. All treat- ments were applied to the center of the plots with a 9-ft-wide boom equipped with XR11002 flat fan nozzles calibrated to deliver 15 gal- lons per acre. Potatoes emerged on May 30, 2017. Plots were rated for crop injury and weed control at 1 and 4 weeks after emergence. Harvest occurred on September 29, 2017. The experiment was a ran- domized complete block design with five treatments receiving rat- ing during the season and four treatments harvested. Crop injury was slight, except for Boundary at 1 week after emergence (Table 1). Dual (metolachlor) liked caused some injury because of the cool and wet conditions. Weed con- trol was relatively good with most treatments. Compared to the non- treated check, herbicides improved total yield of all treatments (Table 2). Andy’s Advice: Effect Of Tank Mixtures With Sonalan (Ethalfluralin) On Russet Burbank Potato Production By Andy Robinson, Extension Potato Agronomist, NDSU/UMN