Category Archives: Tillage

Take More Care of Soil at Harvest

As printed in Grower February 2011

James Powrie and Dan Bloomer LandWISE Inc.

In November LandWISE, FAR and Horticulture NZ held combined field visits to 7 cropping farms.  Visual soil assessments were performed at a range of sites and discussions held about what was seen.

Each farm is experiencing common challenges with soil quality.  All of the farmers visited want more soil quality because of what it means for the future of their operation…and almost all are getting less.  When we say less… digging soil from under a fence shows where the soil has come from, or its natural state.  When this is compared to the cropped soil, there is always a difference.  Often compaction damage is seen as big hard lumps with plant roots growing around their edges. Virtual rocks.

Farmers wanting to move their soil back toward this state have a range of options.
Reduce the use of powered implements –  Powered implements use PTO power to turn a tool at speed.  Soil structure is shattered at point of impact, rather than a natural line, worms and other life are destroyed and the natural flow pathways and porosity are interrupted. Depending on severity, full destruction of soil structure can result.  Often the progressively damaged structure requires increasing use of powered implements to create tilth.

Reduced traffic – Any practical mechanised system involves field traffic and compaction of soil, usually by wheels. Wheels cause soil damage, but this can be limited to a small proportion of field area by restricting all heavy wheels to permanent traffic lanes. Adoption in NZ and other countries has demonstrated the effectiveness and practicability of Controlled Traffic Farming (CTF) systems in very different cropping environments.  Less trafficking means less remedial tillage is required to remove compaction and this can mean fuel savings and fewer operations.

Comparisons between CTF and conventional “random traffic” cropping systems in NZ are also showing improvements in soil quality, crop performance, time savings and a range of other gains.  Data from extensive grain production systems in Australia indicate that CTF could provide a major reduction in cropping emissions and massive improvements in hydrology.  CTF can improve productivity, and all measures of sustainability; it also overcomes some important constraints to the adoption of conservation agriculture.

As precise guidance becomes progressively cheaper, machine system width compatibility remains the only real barrier to a significant improvement in food security and the environmental footprint of cropping.  Imagined barriers can include tradition, stubbornness or resistance to change.

If soil is recognised as a primary asset on the farm and improvement a goal, then the cost is justified as an investment in the future.  It may be easier to make changes than you expect.  Some changes can create immediate improvements and savings.  With the urgency of better soil care becoming clear, be sure its not rocks in your head causing the rocks in your paddocks.

For more information on how farmers in NZ are making these changes and support with yours, talk to James Powrie (LandWISE) or Dan Bloomer.. Funding for this work has come from the Sustainable Farming Fund ‘Advanced Farming Systems’ and ‘Holding it Together’ programs.

Rocks we make in our soil – field sessions on soil care and reducing costs

Last week LandWISE completed a national round of field discussions in conjunction with HortNZ and FAR. The round started at Lawson’s Organic Farms in Hastings and finished at Peter and Emma McCracken’s farm at Rangiora where they grow onions, cauliflower, pumpkins, lucerne and maize.

Discussions were focused on soil care and cost reductions with reference to managing traffic and cultivation options. Over 100 farmers participated in the sessions from Pukekohe to Canterbury and looking at systems ranging from potatoes and onions, to maize, market gardens, and arable crops.

Visual Soil Assessment was used to observe cropped soils and then to compare them with uncultivated soil from under the nearest fenceline. It is always sobering to see the effects of cropping, particularly when it is continuous. Farmers were able to see the difference between dusty, compacted, platy or grey cropped soils vs the same soil type in its darker, porous, nutty, native state from nearby.

In some instances compaction from traffic and cultivation pans is creating virtual ‘rocks’ in the soil, these are so dense they don’t allow for storage of water or exploration by roots. In each case, after looking at soils, discussions turned to managing traffic and reducing powered tillage and how changes in practises are improving soil condition and farm profitability around the world.

The visits were supplemented with the expertise of a Nuffield scholar, James Peck from PX Farms in Cambridgeshire, and Dr Bruce Ball, a visiting soil scientist from Scotland. Bruce has practised and encouraged reduced cultivation and better traffic management since the 1980s, because it is a solution to many of today’s cropping challenges. As he concludes his Nuffield tour, James commented that he is seeing improved management of traffic create dramatic soil improvements and cost savings at all scales, in Europe and Australasia.

It has been said that farmers make their money with the top 6 inches…. of their head. It is interesting that many innovative farmers reflect on changes they have made and note that many perceived barriers turned out to be imaginary – rocks in their heads….

As new technology offers the chance to take better care of soil, it’s a good time to check for ‘rocks’ in our soil, and in our heads…, and then to explore new and proven options for better care of cropping soils.

Talk to LandWISE if you would like to discuss your options or have us help you meet a farmer who has overcome similar challenges to yours.  Someone surely has.

Contact James for more information on 06 6504531 – 0272 757757 – james@landwise.org.nz

Reduced tillage corn expert from Ohio hosted by FAR

In February Ed Winkle was hosted by FAR to talk to Farmers about reduced tillage in corn and soybeans in the USA. Ed spoke at the FAR Maize day and then visited farmers around the North Island to look at maize and corn planters and discuss planter setup options.

He visited 3 LandWISE farmers while in NZ, David Clark, Hugh Ritchie and Hew Dalrymple, where he saw how some innovative NZ farmers and contractors are setting up their gear.  Ed has modified planters for himself and other farmers in the US and believes that similar methods would work well in New Zealand conditions.

How Ed’s cropping system works

Ed buys farms and works on drainage first, retiling and draining as required. He then works on pH and soil fertility to eliminate any limiting factors.

His grandfather planted over 4 months but Ed targets the best 5 planting days. Timing of planting is aimed at catching plenty of sun on the longest day.Timing is right for Ed if his best yield comes from his second or third paddock planted. Emergence within a 48 hour range shows that he has achieved even establishment.

Soil resilience has improved quickly with minimum tillage. Water infiltration, drought resistance, earthworm numbers and recovery from adverse events are better. Ed saw very compacted soils on many of the farms he visited in NZ. “If you aren’t already getting some serious soil problems, you’ve got them coming, your soil needs less passes”, he said.

Nitrogen rates are comparable to those in NZ and are set using models based on projected yields. Ammonium sulphate is applied at 100kg/ha which Ed believes aids the microbial breakdown of slash, which is rarely mulched.

Less P and K are being applied to Ed’s farm now than when he started in 2004, and he knows some min till farmers who have applied none in 20yrs. 17 nutrients are monitored in his soil tests and each is held at satisfactory levels with targeted fertilising to ensure yields are not compromised.

Setting up a planter for reduced tillage

The only cultivation done is by the planter itself. It is set up to achieve consistent tilth, cultivation depth, soil cover, seed depth and firming in a single pass. Setup is critical, says Ed. “The planter units should ‘float’ along. If you are working with pressure, you are working against yourself.” And he carries this philosophy through a lot of what he says.

The planter uses 500mm disc to cut trash and soil surface and residue managers clear trash from a 6 inch strip for soil warming and planter performance. Ed uses Keaton seed firmers to ensure each seed is correctly set in the planting slot. Planter performance is monitored carefully with results checked in every paddock.

Pre season maintenance includes measuring disc diameters and any play in moving parts. Out of spec discs are discarded and any loose joints are shimmed or rebushed to ensure consistent results.

Cover crops

Ed sees cultivation as a catastrophic event for a soil. Cover cropping is seen as offering multiple benefits and protecting the soil. It gives something back to the system. Radish is used as a cover crop to provide soil aeration, reduce compaction and capture and store nutrients. It also provides bio fumigation against weeds and pests. In Iowa it only grows for 60 days or so before it is killed by snow. But Ed is an advocate as he sees the significant gains being well worth the cost and effort of planting.

The Benefits

Reduced tillage corn provides great erosion control and improvements in soil properties, but is done primarily for economic reasons. Yield is king and drives profit.

Costs are reduced by fewer passes. Environmental benefits ‘come along for the ride’.

Ed believes many reduced tillage disappointments are simply a result of using the wrong gear and/or setting it up wrong.  The system he is using has been successful across a range of soil types across the US. Corn yields of 11 tonnes / ha are typical in the US.Ed’s yields have risen from 10.3 to 13.9 tonnes/ha in 6 yrs and are climbing.

“Some farmers are happy with [11 tonnes], but I need to pay the bank. I didn’t get given anything, so it has to work,” he said.

Reduced passes and smarter planter setup are the keys to more successful farming. Ed was heartened to see so many NZ planters being set up towards reduced tillage and “saving soil, oil and toil”

Ed’s conclusion: “Make less trips across your fields and make more money!”

Thanks to FAR for hosting Ed.

Evans Farm Precision Agriculture Field Walk, Canterbury

On Monday 16 November 2009, a field walk was held in conjunction with FAR, at John and Jack Evan’s farm in Dorie. This is an Advanced Farming Systems Project farm and includes a strip tillage trial.

James Powrie and Dan Bloomer spoke about the LandWISE Advanced Farming Systems project, what the various farmers are achieving with Precision Ag and the benefits of Controlled Traffic. About 35 visitors attended and saw John’s Trimble GPS guidance at work in mechanical weeding of beetroot seed. And then viewed the strip tillage trial which is in carrot seed production.

John spoke frankly about the warts and all of adopting Precision Agriculture. The principle benefits to him are in reducing overlaps and wasteage and in being able to solve weed control and herbicide efficacy challenges by mechanically weeding. As he becomes more precise with planting, he finds that his demand is lifting for still further precision, so that he can weed closer and faster.

Thanks to John and Jack Evans and FAR.
For further information: Call James on 06 6504531 or 0272 757757, email james@landwise.org.nz or see www.landwise.org.nz for updates.