The LandWISE MicroFarm in Hastings is an attempt to discover and apply best practice for cropping. Our aim to maximise production while minimising the environmental footprint.
We believe the soil has amazing abilities to grow and restore itself if we avoid compaction and over-working. So we want to minimise the area we drive on and do whatever operations are needed at the best time with least structural impact.
We have seen time and time again that controlled traffic systems provide good “roads” to drive on and good gardens to grow in. But are they realistic in a typical process crop regime?
At the MicroFarm, this season started with six paddocks of vining peas for McCain Foods; early peas in early September, late peas in late October. They were followed by four paddocks of green beans and two of sweetcorn.
In September the soil was at field capacity, and it was raining. The forecast promised showers or rain every day for a week. Thankfully, we got the pasture sprayed out while it was a bit drier, though even then the tractor and spray trailer left visible tracks.
Our paddocks are part of the overall “grand plan”. The planners at the factory worked out their through-flow needs on a daily basis. The field staff worked out how many hectares to plant each day. We need to plant when the schedule dictates. The alternative may be less attractive.
Think about risks. The basic idea behind risk assessment is to combine assessments of hazards with assessments of probability that the event will occur. A serious hazard with a high probability of occurring is assigned the highest priority for risk management.
At planting time the average grower is facing many risks, and constantly ranking them in their mind, even if informally. “Not getting a crop planted” might rate higher than “avoiding a bit of compaction”. So we are going to plant. And there is a high risk of soil compaction.
What can we do to reduce the impact of the hazard, to reduce the likelihood of it happening, or to reduce its severity if it does?
The key is planning ahead, and taking sensible steps well in advance of the problem arising. We can plan for this when we have a less stressful period, install drainage in a quieter time, and plan a reduced wheeling strategy well before the season even starts.
We can plan drainage to keep excess water off the paddocks and remove excess water in a timely way. That should reduce the likelihood and severity of damage.
We can ensure our soil is in the best condition possible. That will increase infiltration and drainage rates removing water faster and make it structurally stronger to carry traffic. We can put only essential wheels on only the minimum area of paddock. That will reduce the damage area.
We could remediate. We could aerate after planting to remove compaction, get air back into the rootzone and give the roots a chance to penetrate. That won’t reduce the compaction, but at some financial cost it will help remove it. And the soil is too wet anyway.
Last season we visited minimum tillage sites after operations in sub-optimal conditions. We were very pleasantly impressed at how little damage these paddocks suffered.
We’ll still have to tidy up if we make a mess, but we’ll have to do it less often and more easily.
This posting first appeared as an article in “The Grower” magazine