Farming on the edge with strip tillage
After seeing large-scale direct drill in North Carolina I flew up to Denver and had a (long) drive to Kansas. My host Gabriele asked me if I knew what the national tree was in Kansas: I thought he was joking when he said it was a telegraph pole. But it proved to be pretty true as there wasn’t much along the route apart from isolated farms and a few gas stations.
The temperature certainly ramped up, and while I was there with it hitting 95 degrees – boy does it get hot out there! I visited Kriss, who farms his land on behalf of IFC, a company which owns 150,000 acres across nine states but leases the land back to local growers.
Above: With Kriss, Val from Pioneer seeds & Mike Thompson IFC local agronomist
Kriss had moved to strip-till some years back after what he described as deep ripping to 5-6” and then finding that they had to use their pivot irrigation system to replace the moisture lost through cultivation. This sounded like a recurring nightmare.
Their strip-till approach involves going through with the deep tine system and placing fertiliser some time ahead of the planter, which is always a separate operation. Kriss has been really pleased with his results, but trash management is still crucial and I was once again surprised at the level of tillage that was used.
I saw on his and a couple of other farms that vertical tillage discs were used down to 3” depth to help warm the soil and redistribute trash better; this still left all the trash on top and the discs are straight as opposed to scalloped so there is no inversion. Retaining the surface residue was vital to help reduce the effects of wind erosion and evaporation, but after some recent 70mph winds, even this had blown some corn trash back over the rows and it was staggering to see how much this affected the crop emergence. It illustrated that with no-tillage you need to work with residue, and managing it is crucial.
Below: The effect of wind-blown trash on crop emergence
Without pivot irrigation, farming would be nearly impossible out here and I saw several fields of wheat that were not worth combining. Compared to the UK where getting a good crop canopy early in wheat is more desirable, Kriss said the crop had grown too much in the autumn and had taken out too much moisture ahead of the growing season.
I then visited Mike in Texas who had been really unlucky to be on the receiving end of a hailstorm the night before. The damage was horrendous in some spots, with an estimated 30% of the crop lost to the hailstones. It was just like someone had taken a strimmer to them and Mike was left pondering whether what he had left would make 180 bushels when he would expect to target 260, or be faced with the prospect of re-planting. As he pointedly described “we are farming on the edge out here” and you could easily see the quality of the crops he was producing and how devastating these effects could be. But Mike had also found that using strip-tillage had resulted in a steady improvement in yields on an annual basis and that some of the machines were better than others for creating the channel ahead of seeding.
I was also intrigued to see the amount of crop dusters that were used in the US. They were extremely popular in Kansas and Texas and a lot of growers seem fairly happy with their accuracy, although seeing how important we consider boom height in the UK, I struggled to get my head round it whilst watching one in full flow!
Below: A crop duster in full flight
After the searing temperatures in the mid-west I headed up to North Dakota and thought that there must have been something wrong with my car temperature as it only read 68 compared to the mid-90s that I was used to, but it was true: there was a definite change in temperature.
I travelled the path of many a scholar before me and visited Dwayne Beck in Pierre, South Dakota. Although his findings will have been reported before, for anyone studying no-tillage, it is certainly an essential visit to understand the wider picture.
I spent a terrific day with Dwayne looking at how he was using cover crops and adopting a wide rotation to balance carbon within the soil, and we also looked at some excellent no-tillage crops along the way. Dwayne highlighted the relevance of the historical landscape in determining which crops can be grown successfully. He maintains that carbon should be treated like phosphate and that any removal should be replaced. There should be a balance, so if you have a low carbon returning crop it should be followed with a high carbon returning crop. Conversely, two consecutive high carbon crops have their issues.
There was also some great research illustrating that 97% of weed seeds left on the surface had disappeared within three years under no-tillage, but with cultivation the figure was nowhere near this. This correlated with some data I saw in Australia which showed higher weed levels in year two, but a significant drop-off in the subsequent years.
There were so many things we discussed that made it a great day and one of the last things we talked about was the difference between high and low disturbance drills and the amount of diversity they have. Tine drills possibly help guarantee good emergence but come at a price with increased weed emergence, whereas a low disturbance drill will potentially result in less weed emergence but may have lower diversity. He also mentioned the importance of placing starter fertiliser in a band to the side of the seed channel.
I met with a local grower, Kent, who had been doing long-term no tillage, and progressed from tine through to a disc based system. A varied rotation was at the heart of his success, but Kent was also innovative. Frustrated that he couldn’t purchase a 60ft seeder for planting corn with the specification he wanted, he decided to build his own with the best components from different manufacturers.
Above: Kent’s home-built 60 foot seeder.
Not only was his machine on tracks, it was surrounded by a multitude of different tanks for seed and fertiliser etc. When he was discussing the planter Kent thought they had achieved their best establishment with the new machine, the only problem was having enough memory space to run all the screens. How things have changed over the years!
The intriguing thing about the picture above, taken when we went to look at the seeder, was that it had been raining hard all morning and many of the surrounding fields had surface water sitting on them. Kent’s field, though obviously wet, had no surface pooling and showed that improved infiltration rates under no-tillage was not a myth.
If harvest provides a break I will hopefully get a chance to sum up my US trip in the next blog.