P is the owner of Corson County Feeders, Inc. P sued D alleging its agronomist incorrectly prescribed a herbicide that P sprayed on his 2014 sunflower crop. The herbicide was not labeled for use on all of P's sunflowers, and 1,200 acres were destroyed. D provides a variety of agronomy services for growers. The services include recommending chemicals, seed varieties, and fertilizers that D sells. The services also include directions on what herbicides to use on what crops. To properly provide those services, D performs field scouting and soil testing. It also maintains field lists and aerial maps of its customers' crops. P farms 12,000 acres of land and started to grow sunflowers with advice from two D employees: Craig Maher, the D agronomy manager, and Jason Fees, the D agronomist. Each year D provided P with a large binder that contained the plans for what he would plant in each field. The plans were based on soil testing and P's previous year's crop. The plans also included D's recommendation for herbicide applications in each field. P testified that over the years, he had asked D agronomists for direction on what herbicides to use on his crops and that he followed those directions 'a hundred percent.' A mistaken use of a herbicide called 'Beyond' on P's 'non-Clearfield' variety of sunflowers resulted in a loss of 1200 acres of the crop. The Clearfield and non-Clearfield varieties are not distinguishable when growing, but the proper herbicide to be used is dependent on the variety. 'TapOut' is a herbicide designed for use on non-Clearfield sunflowers. The herbicide Beyond is specifically designated for Clearfield sunflowers because that variety has been genetically modified to tolerate Beyond. Non-Clearfield sunflowers do not tolerate Beyond. D sells both of these sunflower varieties and herbicides at its facility. On December 2013, Fees developed a written plan for the 2014 crop of around 3,200 acres of sunflowers. The plan included ordering both TapOut and Beyond. Fees intended P to plant both Clearfield and non-Clearfield sunflowers. Fees testified that around January 24, 2014, P told Fees that P had changed his plan and was only going to plant the Clearfield variety. P denied the conversation occurred. P claims he neither knew what Clearfield sunflowers were nor the difference between the Clearfield and non-Clearfield varieties. Ultimately P planted both Clearfield and non-Clearfield varieties. P contacted Fees for a herbicide prescription. Fees prescribed and furnished Beyond even though P had planted an incompatible, non-Clearfield variety. Applying Beyond killed 1,200 acres of the non-Clearfield variety. P sued D for negligence, breach of contract, and breach of warranty. D moved for summary judgment, claiming assumption of the risk and contributorily negligence. P was a licensed spray applicator in the State of South Dakota and was responsible for reading the labels on the chemicals he sprayed. P admitted he did not read the Beyond label, which indicated it could only be used on the Clearfield variety; and that both P's and D's experts agreed that a reasonable grower should know which fields were planted with Clearfield and non-Clearfield sunflowers. The circuit court granted D summary judgment on an assumption of the risk. The court held that P didn't read the label. As a licensed applicator, he's required to follow the label. P appealed contending that he did not have actual knowledge of the risk; he did not have constructive knowledge of the risk; and even as a licensed spray applicator, he should not be charged with knowledge of the risk.