Why use rockdust in agriculture?

Question

http://www.remineralize.org has the details ... well, some of them.

Answer 1

I'm going to answer this in simplified, layman terms.  I'm a small permaculture farmer, by the way.

Basically knowledge of what plants, animals, and humans need in their diet/nutritional needs has really grown over the years.  

Farmers a long time ago use to do things, because the crops grew best that way, or the livestock was healthiest that way.  They didn't know ALL of the in's and out's...they just knew it worked.

Then after World War II, along came the chemical age in farming.  It was really a great time in science and for farmers.  Vaccines, antibiotics came along.  Chemical fertilizers, and chemical insecticides.  This new chemical age became the hope of mankind.  Scientists, and others honestly thought man would be able to totally control nature, via the correct application of chemicals.

It turns out mother nature really does know best.  You can grow corn with giant applications of chemical nitrogen fertilizer, and alternate it with soy beans, with lime applications, but over time, the soil is stripped.  The trace minerals are all sucked out of the soil.  

The soil will no longer support microscopic life.  It (the soil) becomes virtually sterile and dead.

One of the ways of returning life to the soil is with the application of rockdust.  All kinds of trace minerals are returned to the soil.

I can see the difference on my farm.  This spring will be my fourth year here (Idaho).  My In-Laws owned this farm, before my husband purchased the farm from his parents.  They were from the great chemical generation.  

For years, my Father-in-law applied chemical fertilizers.  He grew up a farm boy, actually farming with draft horses, when he first started farming.  Of course his daddy, and granddaddy had also been farmers.  But he was the first of the chemical generation.

When I arrived four years ago, the soil was grey, loose, dry, powder.  For years hay had been taken from the land, and cattle grazed her part of the summer, but never over wintered.  The land had been stripped since the mid 1970's when the house was built.

I arrived as the brand new daughter-in-law with goats, and horses in tow, and outrageous ideas.  

I fed the minerals to the goats (four different types of mineral blocks) and horses.  The manure from the livestock was applied to the pastures and fields.  The livestock lived here year around.  Their manure stayed here, along with the hay, which of course was returned as manure.  

Nothing left the farm in other words.  Just rich manure, filled with minerals.  In three short years, I have turned the soil around.  It is now dark brown, holds moisture, and clumps when you squeeze it.  The amount of fodder (grass) the pasture is able to produce grows every single year.  The crops continue to improve.

Soil, plants, animals, and humans need the trace minerals just as much as they need sunshine and water.  It just takes longer for the damage of loosing the trace minerals to show up.

The foods that we grow, be it the flesh of animals, or the vegtables from the garden are bursting with vitamins.  The food we produce is truely GOOD for you.

Putting rockdust on the soil, is the same as people taking needed vitamins.  Your giving "vitamins" (trace minerals) back to the soil.  If you put enough trace minerals back into the soil, so that there is some to spare for the plants and animals, the food that is produced from that land will not only taste better, grow better, look better, but it actually WILL be better for you to eat!

~Garnet

Homesteading/Farming over 20 years

P.S.  I forgot to mention the importance of returning minerals to the soil is one of the reasons I put things "your not supose to" in our compost heaps.  Like bones...returns a lot to the soil.  Minerals that were used to build up the animal and help it grow are returned to the soil on our permaculture farm.  We do not strip/rob the soil....we continue to build it up.

Answer 2

The reference you give is pretty straight foward. They recommend dust from glacial rock which would be a mix of many different types of rocks (or minerals). Next choice is mixing seashore and/or river rock dust. In short any mix of rock types would give you a good mix of minerals to the soil. These minerals are the building blocks of soil. I think their best suggestion is adding the rock dust to the compost pile. My personal feelings are that the rock would be a reasonable addition to the soil, but I would doubt the value to the soil would justify the cost of the rock dust unless you were talking about soil for the vegetable garden or flower beds.  The main type of rock dust used on a large farming system is the dust of limestone used to correct the pH of the soil.

Answer 3

Let us be careful to observe that using rock dust is not universally appropriate. For example, our soil is a thin smear of lacustrian soil over glacial till. In our case the extensive mixture of rock fragments from a wide area brought here by  glaciers makes rock dust a moot point.

In an area that gets soil laden flood water, rock dust is unlikely to accomplish anything.

If the available rodk dust is mostly limestone, and your soil pH is high, based on limestone, you would avoid that particular rock dust.

In many places, use of a deep-tillage cultivator can bring up all the rock dust you want. In my own land, it also brings up a lot of rock fragments too.

Answer 4

many many reasons, First to adjust the soil PH(acidity) in the case of lime materials.

Also many types of roocks have been used in the past to add the macro and micro nutrients needed for plant growth like P,K, Ca, Mg, S, Mn,Fe, Cu. These are still used by some farmers now.

Also rock dust could be used to amend soild qualities like pore space and erosion factors

Answer 5

as a source of minerals.  We used limestone on our fields in NC as a source of calcium.  It also added alkalinity to the soil, which is what some crops need.  Like one of the answers above stated, crops need different things to grow, so it would all depend on the plants' needs as to what you put on the soil.

Answer 6

Rock Dust adds minerals to the soil that crops need to grow better and stronger.

Answer 7

it is the same principle as volcanic ash used in farm lands