Controlling the strip
We look at a three-year project to test innovative field cropping practices which builds on previous projects undertaken by LandWISE Inc. Field trials are being carried out to compare new practices against conventional systems.
The project aims to increase the economic and environmental sustainability of field cropping through the development of advanced strip tillage and GPS-guided, controlled-traffic farming, applied in a whole farm context. It was started in 2003, runs until 2006 and is carried out with help from the Sustainable Farming Fund.
LandWISE believes that with finite land, soil, water and labour resources, alternative ways must be found to help producers maintain or improve profitability without compromising environmental values.
Tillage itself represents 20-30% of the cash cost of producing crops and makes a significant contribution to the hidden costs of crop production by altering fundamental soil properties and capital requirements. Strip tillage reduces costs by minimising both the volume of soil cultivated and the n umber of cultivations used. Controlled traffic reduces costs by creating wheel zones and plant zones, improving both traction and friability and avoiding unnecessary overlaps.
Earlier studies by LandWISE and others indicate no tillage and strip tillage can minimise soil impact, alleviate associated problems and increase profitability. Scientific reports suggest water availability and drainage will improve.
Potential advantages include reduced time inputs, reduced irrigation need and increased ability to undertake field operations after rain events. Process industries can see the potential benefits as planting schedules and harvest operations are less affected by periods of adverse weather greatly improving factory efficiency.
LandWISE has joined with industry to co-ordinate a series of on-farm trials focusing on strip tillage for squash, sweetcorn, maize, peas and other crops included in crop rotations. Strip tillage and controlled traffic farming are new in New Zealand and need to be tried under a full range of climates, seasons, soils and crops. The prototype strip-till system developed by LandWISE has been used in comparative trials in recent seasons only. In some cases profit increased, in some it decreased. We need to find out why.
What is Strip Tillage?
Strip tillage aims to retain crop residues, and establish crops with the least realistic amount of soil disturbance while still maintaining crop yield.
As a guide, strip till techniques often involve fully cultivating a strip that is about one third of the row spacing wide. The rest of the soil is left undisturbed, and provides a good carriage way for vehicles passing through the crop. In the case of maize, the strip-tillage drill cultivates and plants 25cm of the normal 76cm wide row spacings
Dan Bloomer, from LandWISE, describes strip-tillage as being halfway between direct drilling and full cultivation. Initially the strip-tillage was introduced on light Hawkes Bay soils to minimise wind erosion, but it is now carried out on a range of soils, including heavy ones, for different benefits. The benefits include spending less on cultivation costs and also gain harvest days during wet weather because the undisturbed soil supports the machinery better.
By adopting strip tillage systems LandWISE hopes to maximise profitability in the short term by avoiding unnecessary cultivation, and in the longer term by maintaining or enhancing soil health. However, because inputs and yields may vary under different production systems, it uses a gross margin analysis to compare results. If gross margins and soil health are similar, the result is a break even.
Strip Tillage Trial Programme
The base of the LandWISE programme involves commercial strip tillage crop trials. Each is replicated five times, using a split paddock design with conventional practices providing a comparison of system performance. Demonstration sites allocate a minimum of 1ha to each treatment within larger cropping paddocks.
In comparing strip tillage with conventional cultivation, the best practice for that particular production system is used. Herbicides are used as deemed necessary according to crop and weed species present, and this may vary depending on cultivation used. There are 22 sites established on farms around the North Island.
Key factors for analysis include soil quality, plant performance and economics. Soil structure and load bearing capacity is monitored, along with fertility and biological activity, root requirements under strip tillage, crop development, yield and quality. Weeds, pests and diseases are monitored to note any trends that are attributable to changed farm practices.
Location
Hew Dalrymple and group of 4 other Bulls area cropping farmers have clubbed together and bought/built a strip-tillage machine. This is the first year of operation. The cost so far is estimated at around $25,000, which is very reasonable for the probable benefits that it will provide in lower fuel costs, extended harvesting time and improved soil structure.
Hew has a large bull farming and lamb finishing business with his brother covering 2000ha, which facilitates the rotation of paddocks for cropping, mainly maize for grain, export squash and wheat. This year they have 300ha of maize, 135ha of squash and 80ha of wheat, all of it conventionally cultivated and sown with large gear.
Average yields are 10T/ha maize grain (varies from 8 to 15) rising to 13T/ha under pivot irrigators, which the Dalrymples are installing. Maize grain and wheat go to a local poultry farmer.
The newly acquired strip-tillage machine is still being used experimentally on maize, over the same ground strip-tilled last year, with good results. Hew also hired another strip-till machine consisting of ripper and rotary hoe to use establishing some squash this year, with outstanding results. That machine was capable of working up pasture ground.
The new group-owned machine was imported from the US, with one of the members of the group building the main bar. It is an eight-row machine planting at 75cm centres over 6 metres in width. It does cultivation only, not planting. The maize planter has not been modified, as it delivers seed and fertiliser on the standard 75cm row widths, only where strip cultivation has occurred.
The machine basically came too late for this season, so it is early days for calculating the cost-savings and benefits, Hew said. But significant savings of labour, time and fuel are expected, along with steady soil structure improvement. He expects the strip-till cultivation machine to need 200Hp, maybe more, to pull over 6m width. However work effort needed from the tractor could be down to 25-30% of before, bringing massive savings in fuel. This will be a very significant saving.
In the first year of strip-till vs conventional comparison under maize he said crop growth and yields were about similar. This year the bulk of the strip-tilled crop looks better than the conventional, because the soil is in better order, being more friable.
Hew is watching the weed and pest issues in strip-tilling, including the improved slug environment in the maize stubble from last year left unincorporated (between this years planting rows) and the nightshade growth, which needed glyphosate control before maize emergence. He doesnt expect pathogen issues in the soil because new strips are cultivated between last years strips.
The long-term benefit of strip-tilling will be in improved soil structure in the Bulls area sandy loams, with less compaction, he believes.
The project aims to increase the economic and environmental sustainability of field cropping through the development of advanced strip tillage and GPS-guided, controlled-traffic farming, applied in a whole farm context. It was started in 2003, runs until 2006 and is carried out with help from the Sustainable Farming Fund.
LandWISE believes that with finite land, soil, water and labour resources, alternative ways must be found to help producers maintain or improve profitability without compromising environmental values.
Tillage itself represents 20-30% of the cash cost of producing crops and makes a significant contribution to the hidden costs of crop production by altering fundamental soil properties and capital requirements. Strip tillage reduces costs by minimising both the volume of soil cultivated and the n umber of cultivations used. Controlled traffic reduces costs by creating wheel zones and plant zones, improving both traction and friability and avoiding unnecessary overlaps.
Earlier studies by LandWISE and others indicate no tillage and strip tillage can minimise soil impact, alleviate associated problems and increase profitability. Scientific reports suggest water availability and drainage will improve.
Potential advantages include reduced time inputs, reduced irrigation need and increased ability to undertake field operations after rain events. Process industries can see the potential benefits as planting schedules and harvest operations are less affected by periods of adverse weather greatly improving factory efficiency.
LandWISE has joined with industry to co-ordinate a series of on-farm trials focusing on strip tillage for squash, sweetcorn, maize, peas and other crops included in crop rotations. Strip tillage and controlled traffic farming are new in New Zealand and need to be tried under a full range of climates, seasons, soils and crops. The prototype strip-till system developed by LandWISE has been used in comparative trials in recent seasons only. In some cases profit increased, in some it decreased. We need to find out why.
What is Strip Tillage?
Strip tillage aims to retain crop residues, and establish crops with the least realistic amount of soil disturbance while still maintaining crop yield.
As a guide, strip till techniques often involve fully cultivating a strip that is about one third of the row spacing wide. The rest of the soil is left undisturbed, and provides a good carriage way for vehicles passing through the crop. In the case of maize, the strip-tillage drill cultivates and plants 25cm of the normal 76cm wide row spacings
Dan Bloomer, from LandWISE, describes strip-tillage as being halfway between direct drilling and full cultivation. Initially the strip-tillage was introduced on light Hawkes Bay soils to minimise wind erosion, but it is now carried out on a range of soils, including heavy ones, for different benefits. The benefits include spending less on cultivation costs and also gain harvest days during wet weather because the undisturbed soil supports the machinery better.
By adopting strip tillage systems LandWISE hopes to maximise profitability in the short term by avoiding unnecessary cultivation, and in the longer term by maintaining or enhancing soil health. However, because inputs and yields may vary under different production systems, it uses a gross margin analysis to compare results. If gross margins and soil health are similar, the result is a break even.
Strip Tillage Trial Programme
The base of the LandWISE programme involves commercial strip tillage crop trials. Each is replicated five times, using a split paddock design with conventional practices providing a comparison of system performance. Demonstration sites allocate a minimum of 1ha to each treatment within larger cropping paddocks.
In comparing strip tillage with conventional cultivation, the best practice for that particular production system is used. Herbicides are used as deemed necessary according to crop and weed species present, and this may vary depending on cultivation used. There are 22 sites established on farms around the North Island.
Key factors for analysis include soil quality, plant performance and economics. Soil structure and load bearing capacity is monitored, along with fertility and biological activity, root requirements under strip tillage, crop development, yield and quality. Weeds, pests and diseases are monitored to note any trends that are attributable to changed farm practices.
Location
Hew Dalrymple and group of 4 other Bulls area cropping farmers have clubbed together and bought/built a strip-tillage machine. This is the first year of operation. The cost so far is estimated at around $25,000, which is very reasonable for the probable benefits that it will provide in lower fuel costs, extended harvesting time and improved soil structure.
Hew has a large bull farming and lamb finishing business with his brother covering 2000ha, which facilitates the rotation of paddocks for cropping, mainly maize for grain, export squash and wheat. This year they have 300ha of maize, 135ha of squash and 80ha of wheat, all of it conventionally cultivated and sown with large gear.
Average yields are 10T/ha maize grain (varies from 8 to 15) rising to 13T/ha under pivot irrigators, which the Dalrymples are installing. Maize grain and wheat go to a local poultry farmer.
The newly acquired strip-tillage machine is still being used experimentally on maize, over the same ground strip-tilled last year, with good results. Hew also hired another strip-till machine consisting of ripper and rotary hoe to use establishing some squash this year, with outstanding results. That machine was capable of working up pasture ground.
The new group-owned machine was imported from the US, with one of the members of the group building the main bar. It is an eight-row machine planting at 75cm centres over 6 metres in width. It does cultivation only, not planting. The maize planter has not been modified, as it delivers seed and fertiliser on the standard 75cm row widths, only where strip cultivation has occurred.
The machine basically came too late for this season, so it is early days for calculating the cost-savings and benefits, Hew said. But significant savings of labour, time and fuel are expected, along with steady soil structure improvement. He expects the strip-till cultivation machine to need 200Hp, maybe more, to pull over 6m width. However work effort needed from the tractor could be down to 25-30% of before, bringing massive savings in fuel. This will be a very significant saving.
In the first year of strip-till vs conventional comparison under maize he said crop growth and yields were about similar. This year the bulk of the strip-tilled crop looks better than the conventional, because the soil is in better order, being more friable.
Hew is watching the weed and pest issues in strip-tilling, including the improved slug environment in the maize stubble from last year left unincorporated (between this years planting rows) and the nightshade growth, which needed glyphosate control before maize emergence. He doesnt expect pathogen issues in the soil because new strips are cultivated between last years strips.
The long-term benefit of strip-tilling will be in improved soil structure in the Bulls area sandy loams, with less compaction, he believes.