Sawdust could save soil

With regards to nitrogen runoff from farms practicing intensive dairy.

Firstly, most farmed New Zealand soils are silt or silt life, given all the mechanical damage caused by pugging the use of chemicals to control weeds.

Bigger cows and more efficient cows and no fallow being plausible.

What will be the long-term prospects for the soil? Science is so deductive and focused on productivity, would it consider such a complex thing as soil building if it’s not some product to be sold?

I’ve tried filling sacks with sawdust, placing the sacks strategically where runoff might be considered to concentrate and enter riparian areas.

I postulate that the secure environment of the sack will provide a stable environment for denitrogenase bacteria to assimilate the soluable nitrogen.

Sawdust is granulated and porous, over time the bacteria will use the sawdust, nitrogen and other elements to produce humus.

By being such a convoluted path through particles of sawdust/ carbon, the bacteria will have time to process the runoff.

Does it work? It looks like it does. This doesn’t take up much space though the sack does start to disintegrate.

We have a large foresty industry here. They could supply the sawdust. The bigger cost would be the labour.

Better soils would help aeration warming the micro organisms. It would mitigate the negatives of drying and water logging.

Some research on optimising and evaluating such an idea would help the river and the land. Kevin Wells

Palmerston North