Presenting at the On-Farm Research Summit, University of Minnesota soil scientist Dan Kaiser updated attendees on the potassium fertility guidelines for corn. Potassium fertility is a complex discussion. “If you look at a lot of our historical trials, many have been in areas we’ve typically seen potassium responses. Being able to get trials in the northwest is advantageous, at least for us, to get a better look at data. Not all soils are the same.” Fertility guidelines are a work in progress. “I’m considering how we divide our recommendations up and how we look at moving forward,” said Kaiser. “Looking at high-clay soils with 200 part per million critical level, if you’re above that, there’s typically a low probability of a yield increase. There’s been questions about 150 to 200 and it depends on your soil type. I am recommending potash at that given soil test for corn and soybeans.”
