Today I’m taking writer’s liberty and changing tack
slightly. While we’ve been talking about variability and how to manage it and
irrigation efficiency I’m going to share some insights from the knowledgeable
Jim Wilson of Soil Essentials in the UK who is currently out in NZ sharing his
almost 20 years of Precision Agriculture (PA) insights from the other side of the
world with us.
This morning the Foundation for Arable Research held a field
day at Craige Mackenzie’s place near Methven to talk about ‘Practical use of
Precision Agriculture: A global perspective’. One of the main questions from
farmers this morning was “where do I start with PA?”. While there are many different places that someone
can start their PA journey depending on what they’re most interested in and
where they see the most benefit the moral of the story today was to start where
you’d see the most benefit or return from your investment. If the biggest
expense to your business is fixed costs (eg labour, diesel etc for planting
etc) then GPS and Autosteer is the likely starting point for you. If your
biggest cost is your fertiliser bill then, grid sampling and variable rate
fertiliser is likely the best starting point for you and if the cost of water
and irrigation one of the biggest costs to your business, then EM Surveying and
variable rate irrigation are likely your starting point. The key is to know
your business and where your biggest & fastest gains can be made from
utilising these PA techniques. Precision Ag at the end of the day is about
fully utilising all of these tools and technologies to MAXIMISE ON FARM
PROFITABILITY.
Jim Wilson &
Craige Mackenzie up the Mt Hutt skifield access road
assessing the variability
over the Canterbury Plains.
Another key theme that came from today was the use of yield
mapping. While Jim said that adoption of yield mapping is still growing with his
customers and in the UK in general, he emphasised that it was one of the most
important layers of information on a cropping farm to help identify and
quantify areas of yield variability and what that variability is. He said it
was also a really important layer particularly for Scottish farmers (as you could
imagine) they don’t like to spend money where it doesn't make them any. The yield maps enable them to identify areas of interest and manage them accordingly.
Jim Wilson talking
at FAR’s field day on Precision Agriculture with soil variability
and
topography variability in the background.
Other PA techniques that are used widely in Jim’s area of
the world are grid soil sampling and variable rate seeding. Grid soil
sampling is where a soil core is taken in a uniform fashion across a paddock at
either 4 samples per hectare for pH or 1 sample per hectare for phosphorus,
potassisum magnesium, calcium & sulphur. This allows them to
then variable rate apply fertiliser based on these soil test results. Variable rate lime application based on pH test results
is very common in the UK and has a significant return on investment, usually
resulting in savings of lime of approximately 50%. Variable rate seeding on the
other hand is where the seeding rate is varied according to soil type and the
soil’s yield potential. Heavier soil typically gets a higher seed rate than
lighter soil where less seeds are planted to allow less competition between the
plants and optimally more seed fill per plant.
All of these techniques talked about today by Jim are by no
means new to New Zealand’s precision ag scene, however some are done to varying
degrees here.
So, what’s the take home messages from today?
- Start your Precision Ag journey with what will give you the biggest financial change
- Use your yield maps and turn them into something other than pretty wallpaper – talk to someone in the know on how they can be made useful J
