Wednesday, 18 July 2018

Precision Ag update - a UK & Europe perspective - Part #1

Having just spent most of June in the UK and Europe on a tour organised by CB Norwood, looking into Precision Ag, I thought I’d give an overview of what I saw of interest.

The tour group consisted of a great mix of farmers, contractors, CB Norwood’s managers, from both the South and North Island, Tim Myers (CB Norwood CEO), myself and was run by Paul Collins (CB Norwood Partnership Development Manager) - hats off to him for an excellent job managing the whole event and his team back in NZ.

The first week was spent in the UK, going around farms and visiting the Cereals event near Duxford. There was a real mix of farms from the traditional Estates, to new corporate farms less than 10 years old with huge areas 15,000+ hectares. From the precision ag point of view, it was interesting to see that we are all using the same technologies but for different reasons. EM surveys are used to identify different soil management zones as they are here, but not for irrigation and with little use of the topography data collected at the same time. EM was used for variable intensity of cultivating, and a lot for variable rate seeding. The EM zones are identified and then the soils classified into percentage establishment zones, so then according to your thousand grain seed weight and total population your seed required was automatically adjusted. This combined with using the EM to highlight areas of potentially higher blackgrass burdens - they find much higher levels on heavy soils identified from the EM maps, so they drill at higher seed rates   areas to compete with the blackgrass more. Using variable rate seeding and cultivations the farmers where going far more even looking crops, suppressing the blackgrass marginally more and getting up to 8% increase in yield.

Image 1: Winter wheat VR seed rate from an EM map. 

The EM maps where being used in combination with combine harvester yield maps to create zones for zonal soil sampling rather than grid soil sampling. The advantage there was that you had less samples than grid sampling, so it was cheaper, and you took samples in transects from within each soil zone from the EM map. Most of these farms have no livestock and the fields have been the same size under the same management for a good length of time, which lends itself more to zonal soil sampling.

There was a greater spread use of variable nitrogen from either satellite imagery, drones, N sensor/GreenSeeker type sensors than in New Zealand. The farmers had to use their nitrogen smarter as they had strict limits and timing limitations. This was apparent at the Cereals event on the Yara and Horsch stands to name but two both showing their own real-time sensors.

Image 2: N sensor for real-time VR nitrogen application

Image 3: The Horsch biomass sensor, also for VR N
At Cereals every machinery company seemed to be developing or had its own self propelled sprayer option, from the very basic offering to the other end of the spectrum the Horsch sprayer with its incredible boom technology on the pro plus and nozzle setup, allowing it to follow the crop at a height of just 30cm even on contoured land and almost making it wind proof spraying – with a climate like the UK one, you need to be able to spray at every opportunity you can!

Image 4: The soil pit - a great way to compare root structure in different scenarios

Image 5: There are many different software options in the UK for field inputs and collecting layers of data for smarter farming
It was great to catch up with Jim Wilson and the team from Soil Essentials, one of the few Precision Ag companies who still had a stand at the Cereals Event. The consensus on the Precision Ag front was that there are a lot of interesting and innovative ideas in the pipeline, for growers to use, which is very exciting. 

Image 6: The Soil Essentials team

 All the companies seem to have started from various positions within precision ag but come to the same conclusions on what works best, all of which we are doing here too in New Zealand. Of all the cropping farms there is probably about a 50% uptake in Precision Ag in various forms. Most farms seem to use muck in some form or another to increase organic matter and help with moisture constraints.

The last farm we went to in the UK, was the Beeswax Dyson Farming, owned by the Dyson Company. They had bought over 15,000ha since 2011 and used EM surveys and drones to help them get up to speed on their various soil types to manage them better. They were also heavily involved in environmental schemes like some of the old traditional estates we saw.

Figure 7: Beeswax Dyson Farming, general storage shed

In the next article I will discuss some of the interesting ideas that we came across in Europe. 


Thursday, 5 July 2018

Nutrient Budgets and Farm Environment Plan Auditing

If you live within Canterbury, there is a good chance you have been tied up in the nutrient saga that has come to life in recent years. The environment is a hot topic at the moment and promises not to slow down anytime soon.

A common word bandied around rural communities is Overseer or nutrient budgets (Overseer being the program used to create a nutrient budget). Overseer is constantly being updated to reflect changes in software and science developments.  As I write this, we are currently using Overseer v6.3.0.

In Canterbury, a farm is required to have a baseline nutrient budget which covers the years of 2009 – 2013, which in conjunction with Farm Environment Plans (FEP) often forms the basis for any Land Use Consent to Farm (farming consent) that may be required and a current season nutrient budget using actual farm input data for the most recent season.

Farming consents set a Nitrogen Discharge Allowance (NDA) for a farm, and this figure is not to be exceeded. Farming consents are a way for ECan to draw a line in the sand and monitor nitrogen losses from properties or irrigation schemes to determine how nitrogen losses are tracking. Any farming consent requires auditing of a Farm Environment Plan to be completed within 12 months of granting, then after depending on the grade received (A grade – 3 yearly for an individual farm or 4 yearly for an irrigation scheme, B grade – 2 yearly, C grade – within 12 months, D grade – within 6 months). These audits are carried out by independent (non ECan employed) FEP Auditors who have to audit to  guidelines and templates set by ECan.

Part of the FEP audit includes a section on nutrients, and has two objectives;

                1. To use nutrients efficiently and minimise nutrient losses to water; and

                2. Nutrient losses do not exceed permitted or consented nitrogen limits

For us as auditors to determine this, we must be able to compare ‘apples with apples’ in terms of nutrient budgets. This requires the baseline nutrient budget to have been updated into the most recent version of Overseer (currently v6.3.0) and the most recent season end nutrient budget to have been completed in that same version.

If we are unable to determine if the farm is operating within its NDA, we cannot grade objective 2 very highly which could mean the difference between an A or B grade or a non-complying grade (C or D).

Therefore to ensure your FEP audit grade is not impacted, make sure your baseline nutrient budget has been updated to the most recent version of Overseer, and that you also have a nutrient budget that reflects the most recent season on the farm.

By Ben Howden, Irricon Resource Solutions
Phone 021 242 0023 or email

Wednesday, 20 June 2018

Winter Grazing

It always amazes me how quickly time flies – as I write this, we are in June of 2018 already and winter is upon us.

With the onset of winter comes the slowing (or stopping) of pasture growth and the need to supplement feed with crops or imported supplements, so it is timely to discuss winter feed management and the environmental perils associated with feeding winter crops and supplements.

It’s a hard road finding the perfect paddock to plant your crops in, if the soil is too heavy the chances of pugging and the loss of soil and faecal matter is higher and if the soil is too light, the drainage is great but with more drainage comes higher nitrogen leaching, particularly in areas of high rainfall.  Planning ahead and selecting the right paddock or even the right areas within a paddock to grow crops can reduce the environmental risk.
There is a lot of information about good practice for feeding winter crops available, but as for any farming practice there is no one size fits all and it is a matter of taking those good practices that apply to your situation and putting them in place.  The key issues with the intensive grazing of stock over winter are the loss of soil and faecal matter through run off into water ways and the leaching of nitrogen into groundwater from intensive stocking. 

Any management practices that can be implemented to reduce run off into waterways are beneficial, this can help to reduce the soil/ sediment and faecal contamination of waterways.  These include grass strips or margins not planted in crops alongside waterways and planning the direction of cultivation so that it doesn’t lead to a flow path into a waterway carrying contamination with it.
Planning ahead and having a back up option such as taking the animals off the crop, allowing animals access to another paddock or grazing for only a few hours can make all the difference when the weather is too wet for intensive grazing.  Troughs and supplementary feed can be placed strategically so that pugging is minimised in these areas and so that if there is pugging it won’t run off into a waterway.

Some regional plans include rules with regards to the wintering of stock including requirements for intensively grazed stock and stock on winter crops to be excluded from waterbodies.   There may also be rules around standoff areas and feedpads to minimise the environmental impact of these.  In my view these rules constitute the absolute minimum with regards to the good management of stock in winter. 

For information on industry good practice, see the Beef and Lamb website, Deer Industry NZ or the DairyNZ website, in particular the following link provides some useful information which can be applied to beef cattle and deer also -

Post grazing, following the crop with a whole-crop cereal silage crop, before putting the block back into winter crop, can greatly reduce the nitrogen in the soil and therefore, leaching. 

So, with winter already here it is not too late to do some research and plan how you will manage your winter grazing this year.

Lilian Sherman, Irricon Resource Solutions Limited (NI).
Phone: (021) 378 308

Friday, 15 June 2018

EM Surveying - other uses for the data

Today it's our final blog for the 4-part series on EM Surveying that we've run you through over the last month. To date we've covered off:

Today Chris is going to take you on a run-through of what some of the other uses are for your EM Survey data are & how they can be applied on farm...

...I touched on probe placement at the end of the last post, so will continue where I left off. The EM layers are very useful for making sure you have your moisture probe in the most indicative soil type if you only put one probe in under a pivot for example, or if you have several soil types it ensures you can put probes under the lightest, heaviest and average soils, to make more informed management decisions on irrigation application. The topography information collected at the time of survey can also be used for determining soil moisture probe locations. 
Figure 1: Shallow EM Map with 3 probe locations in the different soil types. 

Where the land is undulating we can bring the elevation data into the equation for probe placement to find a flat area in each of the different soil types. We can also use a moisture probe in a dry land situation for adjusting inputs to the season (such as fertiliser, re-grassing & de-stocking).

When conduiting the EM survey we are using RTK GPS to log the EM data, this topography data and its derivatives are very powerful information layers. We can create water flow maps so you can see potential areas there may be issues for your Farm Environment plans, contour maps, and water flow animated videos as shown below. The Water Shed model mimics a large rainfall event, then over time shows where the water moves from quickly and where it hangs around longer. 

These Water Shed models highlight potential avoidance areas for planting, especially for nurseries and high value crops, in areas prone to heavy rainfall.

As you can see there are many ways people are using their EM survey data, and there are many other uses tailored to the individual client’s requirements. It is generally best to discuss with you your issues then we can work together on using the data to achieve the best solutions for you.

For any more information or to discuss your requirements give me a call.

Chris Smith
Operations Manager @ Agri Optics NZ Ltd 

Thursday, 24 May 2018

EM Surveying - The Uses

In the previous EM survey blog, I ran through the process of conducting the survey, this time I will go through some of the uses.

The data from an EM survey is very useful for irrigation in many ways. The topography data can be used for planning the pivot design itself with your irrigation provider for example working out tower spacing and pivot positioning. The angle of slope can be used to see if the pivot stays within design parameters for insurance purposes as well as design planning.

Figure 1: Contour map on top of elevation map

After the initial pivot or irrigation design plans, we can then look at the EM data itself to determine the amount of variability within the surveyed area. Within the PCT Gateway software we can look at the value and amount of the crop being grown on the area and the cost of installing variable rate irrigation (VRI). The software needs to know the average yield and value of the crop. That way using algorithms it calculates that by not over watering the heavier soli types or under watering the lighter areas you bring the crop yield on those areas up to the average. It looks at the reduction in variability by using VRI as opposed to a blanket application. In the example below the variability from using VRI drops from 30.4% to 4.68%. So, by using the average yield and the price we can see the payback vs the cost of putting VRI on your pivot.

Figure 2: Illustrating the payback from VRI, using an EM map. 

This model just looks at the costs vs savings of VRI from a production prospective. It doesn’t take into consideration savings from reduced water use, power savings, reduced track repairs etc, which will be in addition to this.
The next stage is to make VRI maps up for the pivot, using the different soil zones, predominately we use the shallow EM results. If the area has a lot of variation in topography we can also combine the elevation layers with the EM map to make an application map for the pivot. We can also use other elevation layers to achieve the best solution used for each specific survey, as required.

The map below, shows a three zone EM map, where  red is the lightest soil, green the medium textured soil and blue the heaviest soil. This has been combined with the slope map, where the darker tone indicates a slope of 0-5% and the brighter tone of colour areas where the slope is above 5%.

Figure 3: An EM map and slope map combined to make a VRI application map. Brighter red, green and blue indicate slope for the different soil zones. 

The EM zone maps can also be used for irrigation pod placement, as well as moisture probe placement. If you only have one probe under an irrigation management zone, you want to make sure its under the right area. I will discuss this in more detail in the next blog. In the meantime, if you have any questions about EM surveying please get in touch.

Chris Smith
Operations Manager Agri Optics NZ Ltd.