AUTO steer and variable rate application of inputs are becoming common place in cropping but the livestock industry is not left behind - it is feeling the benefits of precision agriculture for pasture and animal management.
Speaking at last week's NRM SE Pathways to Productivity Expo at Bordertown, Brendan Torpy said it was a misconception that PA was only for larger producers, and that there were significant savings and production benefits for farms of all sizes.
Mr Torpy, who works for independent consulting company Precision Agriculture.com.au based at Ballarat, said the staggering variability of phosphorus, potassium and soil pH within paddocks could be fine-tuned.
By understanding the different zones in the farm, livestock farmers could plant the most appropriate pasture species based on soil types, elevation and aspect.
Mr Torpy said precision agriculture was about getting layers of information from soil fertility mapping, satellite imagery, electromagnetic mapping and soil pH mapping, and combining it with local knowledge to make more informed decisions.
"There are plenty of people and plenty of equipment-gathering data for PA," he said.
"There is plenty of software to integrate data, which allows you and your consultants to view it, but where it has fallen down is the ability to utilise it to make a profitable decision, so that is where we are here to help."
He said the first step was developing a digitised farm map - which many farms did not have - a useful tool for seed and chemical budgeting, negotiating contracting rates and productivity-a-hectare calculations.
He said photos from satellites wear a good way of achieving this.
In addition to taking photos, the five satellites which pass over eastern Australia every day map infrared light, which could be used to calculate Normalized Difference Vegetation Index - a measure of plant health - and available for about $800 a farm.
Mr Torpy recommended livestock producers to analyse imagery available from the past 12-13 years at a certain time to get a biomass average of a paddock.
"Healthy, vigorous pasture stands reflect a lot of near infrared light, not red light, so this reflectance of plants shows where unhealthy stressed pastures are," he said.
Grid soil sampling was expensive but Mr Torpy said PA technology enabled more targeted soil sampling.
He said there could be 25 per cent savings in phosphorus application without production losses, and as much as 60pc savings in lime application.
Precision Ag is the first company in Australia to be able to measure soil pH variation across paddocks, with a detector probe mounted on a Can-Am vehicle.
The probe is inserted into soil at depth of 5 centimetres to 7.5cm, which takes a reading every 10 to 15 seconds. The cost is about $10/ha and includes strategic soil sampling, mapping and travel costs.
The results provide a guide to the best place to take soil samples to calculate lime rates.
Mr Torpy used an example of a 960ha farm in southern NSW, where they made $60,000 in savings or $29/ha, through targeted lime applications of 1.25t/ha, 1.5t/ha and 2t/ha in certain areas rather than a blanket rate of 1t/ha across the whole paddock.
"The greatest return on investment comes from doing farms which have seen lime in the past five to eight years," he said.
"We have done blocks where lime was not applied for 20 years and yes, there is some variability, but often a fair section needs a big dose of lime, not saving much. When there is a good lime history it enables them to cherry pick areas that need a bit of a boost."
* Full report in Stock Journal, April 17, 2014 issue.
Catherine Miller
Stock Journal's livestock editor and South East correspondent.
Stock Journal's livestock editor and South East correspondent.
