By Harold Watters, Ohio State University Extension agronomist
I have friends in ag retail who sell you stuff. Their job is to sell you stuff. Your job is to determine the value and whether or not you need this stuff. At OSU we try to give you guidance on what stuff you need. Make sense?
And the quote “drives me nuts” is from a farmer friend who tried to tell his retailer that he doesn’t want the extra juice that they insist is “just $5 an acre.”
Micro-mixes — Do we need to add micronutrients?
Our soil tests are most reliable for pH, phosphorus and potassium and can work reasonably well for zinc, and with a high pH we can predict a Manganese tie up. We usually use a combination of soil and tissue tests to determine micronutrient deficiencies.
Typically we will see deficiencies occur in small isolated areas of a field first. When these are noted, pull both a soil and a tissue sample out of the “good” area and out of the “poor” area — compare the results. Also check a recent yield map for losses in that area. Nutrient deficiencies I saw last year and the year before are potassium from early dry conditions and occasionally sulfur — neither of these are micronutrients however.
Are we short on sulfur yet? Maybe, in some low organic matter soils — but generally probably not. In trials I have conducted over the past 6 to 8 years, I have seen an increase in yield from the addition of sulfur one time — but this year again I put out my plots just to check. State-wide I have seen the results of perhaps 70 trials, and only 3 or 4 that showed a response.
Magic-mixes — Do we need to add humic acid, bacteria, seaweed, or growth regulators?
What about that other “stuff” that costs just $5 an acre? I regularly check out those advertisements, and listen to the sales pitch at farm shows but usually walk away without making a purchase. I recently had a farmer tell me about a product that was absolutely the “best ever, and guaranteed to boost yield.” I asked him why I never heard of it? Because if it’s that good, there would be 25 university tests showing how great it is… and we (university agronomists) would be telling everyone about it.