Some soil chemistry revelations

I just read a brief article that was primarily addressing soil pH here in our area and I ran across a couple of unusual points I hadn’t read before.

1) soil pH drops as organic matter breaks down. Okay, that kinda makes sense.
2) soil pH is more stable (better buffered?) the higher the organic matter level.
3) use of legumes can reduce soil pH as root nodules will add H ions to the soil.

So, if you want to amend and build your soil but need to raise the pH as well, raise the pH before dramtically increasing organic matter levels.

They also made the point that the use of no-till practices may decrease soil pH more in only the upper 2-3 inches of soil and that drop may be masked or reduced in your soil test since test samples are usually plugs going down 8-12 inches. Hmmmm.

So the bottom line was, sooner or later the pH is going to drop to where maximum crop production will be a problem. Seemingly as part of what happens to soil when we’re cropping it. So be aware and amend when needed. Unfortuunately, lime is not something the big farmers out here use, so it’s hard to find and apply in any quantity (like 1T/ac).