There was a bit of a drive today, heading south down the coast, just past Timaru.
This farm is a bit different to those I have been seeing in Mid Canterbury for the last few days. It is out of the prime dairy area, and as such land sells for about NZ$20,000/ha, half the price of that found further north. The climate here is not dissimilar to East Anglia, with 550ml or rain per year, although it is generally hotter – a limiting factor on the wheat yields they can achieve.Michael Porter farms 400ha of cropping land, and a further 80ha in permanent pasture. It is all unirrigated. He runs a flock of 1,000 breeding ewes, and finishes all the lambs himself – along with a few hundred more that are brought in each winter. Almost all his meat is taken by Waitrose in the UK, who like the fact he can provide full traceability from birth to plate. This pays a 10-15% premium, which seems pretty handy to me.The sudden removal of subsidies back in 1984 had a big effect on this farm, and Michael says they are only really starting to get out of its shadow now. One of the results of this was a lack of funds to invest in machinery – hence the 40 year old tractor and 30 year old combine that are still in use today. Michael was pretty excited that a new combine was going to be coming for next season, as a lot of the farm is on steep slopes of up to 37%, and these old combine sieves lose a lot of grain at those sort of angles. You can tell he farms somewhere steep; he is the first person to tell me “I know from experience that my sprayer tips over at 27 degrees”.
Rotations here are broadly similar to what we grow in the UK, but he does still have access to the lucrative and soil-improving ryegrass seed market. Wheats yield an average of 8-9t/ha, OSR around 3.5t/ha, and a typical rotation would go Winter Wheat -> Winter Barley -> Ryegrass -> OSR/Peas. Perhaps unsurprisingly, Michael says his biggest problem is with grass weeds! For the last decade he has been using a Cross Slot, having given up the plough. He uses starter fertilisers on all the crops, and to satisfy some (one) of my readers I shall now list these more precisely. Please feel free to skip ahead.
- Ryegrass has 90-100kg/ha of DAP, depending on soils
- Wheat and barley has 80-90kg/ha of DAP, depending on soils
- Brassicas have 150kg/ha of DAP, plus 90kg/ha of SOP, and small quantities of boron
- Peas have a blend called Cropcare 15, which I cannot find the precise analysis for. It is an NPK blend (Michael thought maybe 20-10-10), plus sulphur and trace elements [Edit: It is called Cropmaster 15 and is 15-10-10 + 7.7S. That’s elemental P,K,S by the way]
When we dug some holes in the OSR field (pictured above), there was an incredible population of worms – perhaps even more than in David Ward’s field on Day Eight.
Once again I was lucky enough to be able to compare a long term no-till soil to a min-tilled (some sort of Lemken disc cultivator) one literally just over a fence. The cultivated land had been growing peas, and so had been untouched since the spring, the no-till had been growing wheat. Predictably, the no-tilled was much more crumbly, particularly in the top two inches. The cultivated soil would compress into a plasticine-like ball, which was not possible over the fence. Most noticeable though were the worms. Each small shovel full from the no-till had maybe 4-5 easily findable (less though than in the OSR field earlier), but in around 10 holes next door we saw two worms in total.
Against my expectations, the no-till soul was actually lighter coloured than the cultivated – it would be interesting to measure the organic matter levels in each of them. It is fairly clear in the picture above though that the texture is significantly different between the two samples. there are many more little roots present on the left, but I suspect this is probably because of the wheat crop that was growing in it.
I asked Michael if his soils had improved much since he started no-till. He answered “Yes, but not as much as I thought they were going to”. This is not the answer I was expecting, and he explained that some of the fields had been on a gradual decline for years, which he had expected no-till to turn around. when it did not, he had to look elsewhere for answers. One particular field yielded 40% less than its neighbour, and had soil that stuck tightly together, making biennial subsoiling necessary. Having run out of ideas, he got in a local fertiliser firm that uses the Albrecht method. The test results are shown above.
I won’t go through them in detail as I am not clever enough, but the basic problem seemed to be a lack of Magnesium and Potassium. The recommendation for this field cost NZ$1,000/ha to apply, but they went ahead anyway. Michael’s attitude is that if he is going to try something (and there are lots of little experiments happening all over the place), he will do it with 100% commitment, “otherwise if it goes wrong, I will always wonder what could have been”. In the first year there was no yield effect. In the second year things started to improve, and after the third year yields were no different to the other fields around it. I don’t know how long the payback period for that NZ$1,000 was, but with a 40% yield increase it cannot have been very long. He now takes his two worst fields each year, and runs them through this sort of program. Fair to say Michael is a believer in the system.
Just going back to yesterday for a second – Ben Tait said that on some of his land “the stones hold hands”. I thought this was an exaggeration until I was out for a walk today and came across this field with what looks like a new crop of ryegrass. No wonder the drills wear out.