This is nothing new. We've been discussing this for a long time. But these charts are new. I am leading a webinar on January 12 and in my preparations for that I made these charts.
I wanted to explain why I don't worry about micronutrients.
I'm going to explain this in words first, and show the charts at the very end. There are two main reasons why I don't worry about micronutrients.
First, the quantity of micronutrients used by the grass, when compared to the amounts of N, K, P, Ca, Mg, and S, is indistinguishable from zero. The grass uses micronutrients in such tiny amounts that it seems the grass can surely get such tiny amounts from the soil.
Second, and this is connected to the first reason, the quantity of micronutrients used by the grass is almost nothing. So there is no excuse for having a deficiency of any micronutrient, because even to apply two or three times as much micronutrients as the grass can use will cost essentially nothing.
Take those two reasons together, and you can't lose. You will probably never have a micronutrient deficiency, And you can spend almost nothing and be sure to prevent one. Sounds easy to me. Which is why I don't worry about it.
Here are three charts to demonstrate what I mean.
First, this is the concentration of elements in turfgrass leaves. You'll notice that the concentration of micronutrients in leaves is indistinguishable from 0.
That's reassuring. The soil can probably supply almost all that the grass can use. But what if the soil can't supply that much?
No problem! The amount the grass uses is so small, it costs almost nothing to supply it.
If you have a 50,000 dollar fertilizer budget, and if all the elements cost the same, you would spend less than 60 dollars for each of the micronutrients. So if the amount used by the grass is so low, it seems easy to apply that much, and to afford that much, as fertilizer.
Of course not everyone has a 50,000 dollar fertilizer budget. What if your fertilizer budget is 700 dollars? Well, the grass won't distinguish between budgets, but it will still use nutrients in the same proportions. In this case, for a 700 dollar fertilizer budget, each of the micronutrients comes in at less than $1.
I hope this makes it clear why I don't worry much about micronutrients. You will probably not be deficient. But if you are worried about it, apply them. It will cost almost nothing.
Of course, if you are spending a lot of money on micronutrients, or are supplying a lot more than the grass can use, it would be prudent to ask yourself "What am I trying to do?"