Through a combination of paddock zone mapping and soil and plant testing, livestock producers are achieving improved pasture production with decreased input costs.
The latest in precision agriculture technology has helped to formulate new pasture mapping systems that incorporate normalised difference vegetation index data across multiple years of stacked imagery to accurately determine production zones of low, moderate and high plant growth.
Through this new technology, Coopers Farm Supplies agronomist Craig John has helped livestock producers throughout the Adelaide Hills and Barossa Valley regions increase total season pasture production across each zone through cost-effective applications of various fertiliser, lime and gypsum inputs.
NDVI stacked imagery produces a paddock map with a different colour for each low, medium and high zone to demonstrate levels of plant density, while soil tests help to determine the nutrient levels within each zone.
The soil test determines soil pH and which nutrients are low or high, such as nitrogen, phosphorous potassium, sulfur and trace elements.
The pasture NDVI map generated for each paddock is used to accurately select pinpoint locations within each of the production zones during the soil and plant sampling process.
"The pasture imagery is collected in late winter and early spring while paddocks have been spelled from grazing or closed up for silage or hay production, to limit any interference from livestock," Mr John said.
"A satellite measures the infrared reflecting off plant leaves to determine plant density across a paddock," he said.
"It is about knowing your paddock zones or areas where to best target your money spent on fertiliser inputs and not taking a blanket approach."
Mr John said the technology aimed to improve low-production zone areas but high-production zones of a paddock were equally important.
Results from 58 hectares of pasture at Flaxman Valley showed that only the low growth zone required lime.
The low production zone received 2.5 tonnes/ha of lime, which provided an additional 900 kilograms of dry matter/ha for the season, and the producer also saved $60/ha through only applying lime across the low zones.
As dry conditions continue to cause limited feed supplies, zoning paddocks can also significantly lower feed costs.
"Compared with buying in good quality pasture hay at a present feed cost of about 35 cents/kg of DM, improving pasture response through better fertiliser input decisions can lower feed costs to under 20c/kg of DM," Mr John said.
Tech adoption creates savings
THIS year, graziers Laura and Graham Ragless made a commitment to boosting pasture growth through paddock mapping to help finish cattle and sheep in better conditions.
The Raglesses own and operate Puttapa Station, via Leigh Creek, and in the past few years, they have bought five grazing properties stretching from Flaxman Valley to Mount Crawford.
"We needed better country to finish off our cattle and sheep from the northern properties," Mrs Ragless said.
They began mapping their Adelaide Hills and Barossa paddocks to determine where pastures were lacking in nutrients and trace elements.
"In the pastoral country, we have never had to add anything to our pastures but in the hills you do and technology will help us do that," Mrs Ragless said.
Using normalised difference vegetation index stacked imagery, the Raglesses saved $4000 in fertiliser inputs this season.
"This year was a really good season for the mapping because we really needed to weigh up where spending money on inputs was vital," Mrs Ragless said.
She said because of the improved pasture growth, they will be able to run more stock.
"After our cattle are mustered in the north, weaners are finished off on the better quality pastures in the hills," she said.
"We will map all of our properties because we want to utilise technology."
