Earthworms are not just great for fishing bait, but also an indication of soil health.
Or is that actually true?
The origin of this topic popped into my head as I travelled across the Prairies last week shooting agronomic videos. At a couple stops the farmers referenced earthworm populations as an indication of soil health. “Look at the amount of worms on that shovel. That’s some healthy soil,” said one farmer, while another noted there were no worms before they started farming their land.
I asked Peter Johnson on RealAg Radio about this and he replied, “Probably, yes, but you have to be really careful because you can have awesome soil without earthworms.”
In the interview found below, Peter emphasizes that they are not the only sign of soil health, but their presence generally indicates that something’s going right.
Much like an extravagant party with picky guests, if one’s playing host to earthworms, there ought to be an enticing spread of organic matter. A tantalizing buffet of crop residue is what keeps these earthworms coming back for more.
Earthworms, quite understandably, loathe the idea of their food supply dwindling. Therefore, tillage methods that strip the soil of their meals may need a re-look if earthworm populations are important to you.
“If your earthworm populations are declining, you had to do some some management that was not really good long term for soil health,” notes Johnson. “If you change the management and the earthworms come back, the earthworms are telling you that you’re doing a better job to support their population. But it’s the management change that really is the key there, and not the earthworms.”
So, the next time you see earthworms in a field, remember – it’s not just about them. It’s about a shift in management practices that is leading to a change in populations.
Listen to Peter Johnson and Shaun Haney discuss the meaning of earthworm populations