One loney strip of grass was all it took
By: Neil Grant

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Source: Rural News - 13 July 2007

The 162ha Bay of Plenty farm where David Law sharemilks went under water in July 2004; all except half a hectare, which, fortunately, included the farm houses.  Also luckily, the floodwater came because the Rangitaiki flood protection canal overtopped its banks.  Other farms downstream were covered in silt because the stopbanks burst.

It took about a week to pump the surface water away.  Fearing that the saturated soil would need extensive remedial work, Law was delighted when soil tests showed the microbes had survived the flood, and were still active.  Nonetheless, he decided to put urea on half of the land that had been under water to kick-start pasture regrowth.

His manager wanted to maintain the rotation pattern, so the cows went first to the urea pasture, which was long and lush, and then to the shorter non-urea paddocks.

The intriguing thing was, the non-urea paddocks had more grass left after the cows had been on them than the urea-treated paddocks.

Law's inference was that the cows did not need so much non-urea treated grass to eat because it had more nourishment in it.  "It showed us the urea grass was just crap.  That was the last time we used urea."

Stepping back a few years, Law had been looking for an alternative to urea as a fertiliser.  Metabolic problems, such as eczema, were getting worse, and he believes they emanate from soil problems. 

"I had a friend who was involved with bentonite clay, (known as rumenite), who asked me to trial some on my dairy cows.  The rumenite has properties that include absorbing toxins and attracting moisture.  This was dusted onto the pasture every day at the rate of 100 grams per cow.  The rumenite proved a benefit to animal health, but we also stumbled across something that changed the course of our future. 

"We had an early drought, and noticed a green strip in one paddock where the dusting had been too heavy.  Then we had 20mm of rain, and the paddock all turned green.  Later, when the paddock dried off, (after another month of no rain), the green strip reappeared, but this time the strip was like an oasis.  The grass became green and long, with heaps of clover six meters wide.  The rest of the paddock had no grass.

About the same time, I had been to a seminar on compost and organic fertiliser by a soil scientist, Elaine Ingham.  Among the things we learned was a list of things to do to make good compost. 

"Several groups came to look at our green strip, and one guy, Peter Burton, took out his spade and dug up a sod.  It had worms everywhere.  He talked about a fertiliser he was developing that contained compost.  I said that if he could put the rumenite in, recreate the same results and fertilize only twice a year instead of dusting every day, I would give it a go.  He was making his compost to the letter the way Elaine Ingham suggested."

The fertilizer, which is called "dolozest", is based on dolomite; it has basalt rock, and contains natural minerals and other ingredients, including rumenite, compost, and live beneficial bacteria and fungi.  It holds moisture, and creates a good environment for microbes.  Law spread it on 20ha.  Within two months, he could see changes in the soil.  The improved worm activity encouraged him, and after discussion with his father, the whole farm was treated.

"In three months, we could see increased worm activity.  The worms were mixing up the clay layers with the soil, and the grass roots were going down maybe 22-23cm.  We had been using liquid fertilizer, but this stuff blew it away."

This year, an American soil scientist and agricultural consultant, Arden Anderson, held a field day on Law's farm.

"I didn't realize how important what we are doing is.  I didn't do this for other people's benefit; I did it to satisfy what I wanted.  But there is interest all over the country.  It is impacting on what other people want to do."

The change in the pasture is leading to major change in Law's farming practice. 

"Now we are at the stage where the fertiliser is right, we are growing more grass than we can handle.  So we will have to milk more cows.  Last season, we milked 400, this season we are milking 460, and next season we will milk 500.  And all this is on less support land, because we have cut down on our run-offs.

"We use two 14-a-side herringbone sheds, but have nearly finished building a 54-bail rotary shed to replace them.  It has the latest technology, but we have not decided whether to use the feeding system yet. 

"We will sow a third of the farm in Italian ryegrass for the winter.  That will save buying in winter feed.  Last spring, we made 1800 round bales of silage and fed it out.  But if you have got the right number of cows, you won't have surplus grass to make that silage, because the cows will be eating it." (This depends, of course, on where a farm is, and what the climate is like.)

To determine optimum times for grazing, Law is doing brix test on his grasses to test sugar levels. 

"Herbage analysis lets us find out what's lacking, so that we can put on liquid fertiliser to make sure the nutrition of the feed is perfect.  When we were using urea, we were growing 14 tonnes/ha dry matter per year.  Now we are getting 17 tonnes. 

"I know I'm a renegade.  I do things nobody else does.  Sometimes, Dad says, 'What the hell are you doing now?'

"Looking to the future, we will have a new shed to milk our increased cow numbers efficiently, be working towards a perfect soil without urea, and have perfectly balanced grass to achieve the best possible production at the lowest possible cost.  As far as I can see, this is the 'fertiliser of the future'."

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