Luhman: If You are Hot, Your Soil Probably Is, Too

The last couple months have been some hot ones, as temperatures have often been in the 90s with heat indexes over 100 degrees. Weather like this is hard on everybody, and I have been grateful for this job and an excuse to spend a more time in the air-conditioned office.

Weather like this is also extremely hard on livestock and soil biology. Many of you may move your cattle to a pasture with trees for shade, or perhaps you have a portable shade tool to reduce stress on your cattle. But how often do you think about offering shade to your soil biology?

Like people, soil prefers a temperature right around 70 degrees so it can use 100 percent of moisture for plant growth. At 100 degrees I will do whatever I can to get back into the AC as quickly as possible. Soil is the same, and at 100 degrees soil can only use 15 percent of moisture for plant growth – the rest is lost to evaporation.

Now, if it’s 130 degrees, all moisture in the soil would be lost, leaving zero moisture for plant growth. And, at 140 degrees, soil biology is killed and people probably would be pretty close to dead as well.

Further, soil temperature can actually be quite higher than air temperature, and this is why cover on the soil is so incredibly important. Soil left uncovered will be baked by the sun and its biology will die.

Soil biology should be thought of as our livestock below the ground and it is just as important as the livestock above ground. It is the key to healthy functioning soils that can infiltrate and store water, cycle carbon and other nutrients, and produce nutrient-dense forage for our livestock above the ground.

I will share creative ways to keep soil covered in the next Connect newsletter. But for today, remember that when you are struggling in the heat, your soil biology probably is, too.