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EC IL | One thing I never understood until the last few years is that crops uptake WATER at an unlimited rate until they get sufficient quantity of the 1 nutrient that is at the lowest level in the plant. An "under-fertilized" spot in the field in one spot may be low on sulfur, the next spot zinc, the next spot potash, etc., so the plants in each location all use soil water at different rates. Because every plant runs into something limiting (such as sunlight or a nutrient) vegetative growth and reproductive growth plateau.
I would not go against the printed recommendations on the pictured tests unless you have solid proof that specific nutrients are not your limiting factor in 90+% of your fields. Those fertility recommendations appear to be established guidelines for your area. You don't ever want to find out the hard way you got bad information on the internet and have lodged crops that slow harvest to a crawl and drop yields to below profitability. Fertility recommendations need a lot of soil tests too.
Let's say you do an absolutely excellent job of applying cattle manure. Even the best tillage practices after solid manure application do not mix soil well enough to scatter manure to 100% of the root zone, so I would bet 2/3 of each spring crop's root structure will be working off of soil-held nutrients and 1/3 will have 3x more than needed because of manure itself. If you agree with these assumptions, then you actually need to have 3 years-worth of nutrients available for each crop year so the 2/3 of the plants not touching the new manure in their root zones are not yield-limited.
Nitrogen is really the only macro or micro or macro nutrient that will move far in the root zone. Everything else just sits still until a root finds it.
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Do I need fertilizer?