Sunday, March 30, 2008

Soil organisms help ranchers

Intense, low duration grazing builds soil vitality, and increases soil organic matter.

Formulaically, the process described by Manske is very simple; what happens as a result is not.

A rancher chooses three pastures on which to graze the cattle. Starting in the first pasture, the cattle graze for 15 days, and then move on to the next pasture. This is repeated and the cattle find themselves in the third pasture.

Once the cattle leave the first pasture, the soil organisms go to work, converting the organic nitrogen into mineral nitrogen and feeding the plants, building their crude protein.

“Just by changing the management from focusing on dry matter poundage to managing those soil organisms, you can increase the productivity of your land,” Manske said. (Source)

Well observed.

Rhizosperic soil can get awfully puny under long duration grazing. Topsoil pales and topsoil depth is lost, but not to sediment discharge or wind erosion. The in-situ transformation of topsoil to not-topsoil results in the discharge of soil carbon to the atmosphere. The good news is that, unlike wind erosion, water erosion, sheet erosion, or gully erosion erosion, this yet-to-be-named variant of topsoil erosion is reversible.


back40 said...

This ignores the plants and the habits of grazers. Animals should be left in a paddock no longer than 3 days since new growth begins by then. The animals will prefer the tender new growth and so regraze it. This weakens and eventually kills the plants since they exhaust their energy reserves stored in roots to regrow some leaves, but don't get a chance to replenish reserves from photosynthesis by the new leaves.

"Rotation range management of this type was used as far back as the 1870’s in Germany, but United States scientists didn’t start studying the potential benefits of it until 1982."

It has been used since the 1500s. In a sense, nomadic tribes have always used it. It has been studied formally in Europe and the USA since the 1950s, and informally for much longer.

The major issue was paddock construction. The invention of barbed wire made it much cheaper and easier, and light weight electric fences made it even cheaper and easier.

roobaron said...

Interesting research.

I read a book a while back called "Holistic Resource management" Author Allan Savory

There seems to be a whole industry developing around it.

Fencing is an issue, as is management as "set stocking" ala long duration grazing allows people to set and forget rather than active manage their flock or herd.

Blokes I have spoken to who have implemented this have discovered that the stock get into a routine and mill around at the gate to go to the next paddock.