The speed at which green grass grows could translate into higher profits if producers implement precision pasture management.
“The knowledge gap is the first hurdle to overcome to get to precision pasture management”, says Christine O’Reilly, Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) forage and grazing specialist.
Why it matters: Forages have seen the least innovation as far as precision management. More information could mean more productivity.
“Is it really getting a good understanding of how fast does grass grow? How quickly are we accumulating forage?”
Producers have resources to calculate animal demand, especially in anticipation of stored forage shortages, but without data on the speed of grass growth it’s tough to apply precision agriculture to pasture situations, said O’Reilly during the Canadian Forage and Grassland Association 11th annual conference Nov. 18.
“Overall our goal needs to be improving output per acre, whether that’s dollars per acre or pounds of meat or milk solids per acre,” she said. “If we’re not using the data to improve the bottom line on the farm, then we’re just collecting information for the fun of it.”
Not only does data around the rate of growth improve pasture quality and increase carrying capacity, but it also allows producers to set tangible targets and benchmarks to measure against and improve farm profit margins to ensure pasture land contributes to the economic success of an operation.
O’Reilly said unlike yield, which is the season-end measurement of cumulative forage production in kilograms of dry matter per hectare (kg/DM/ha), cover is a point-in-time snapshot of available grazeable pasture (forage inventory) used to calculate the number of grazing days within a paddock.
“Looking at cover helps us make those decisions because it’s here-and-now, it’s right in front of us and it really tells us how much available grass there is to graze,” she said.
Measuring forage height and density
Using a rising plate meter to measure forage height and density is the best option for accuracy and ease of use but it does have some challenges.
Rising plate meters are calibrated for the perennial rye grass mixtures used in New Zealand, not for the complex multi-species mixes favoured in Canada.
Calibration is the largest source of error in any non-destructive pasture-measuring tool, because Canada requires seasonal calibration to take account for growth patterns, and regional calibrations to capture climate differences and specie tendencies. However, there is ongoing research happening to address the issue.
“One thing we don’t know yet is how large of an area one regional calibration could cover,” O’Reilly said. “We don’t know how small a region has to be to have an accurate calibration that will minimize the sources of error when we’re using a plate meter.”
The second challenge is a producer’s reluctance to find the time to measure, but O’Reilly said if you break down the potential profit growth of employing data-driven precision management the hourly rate hits the same level as what a lawyer gets paid.
O’Reilly said she often hears farmers say they don’t have that kind of time to invest in it — however, measuring pasture improves farm profit anywhere from $300 to $600 per hectare (ha), or $150 to $300 an acre.
For example, O’Reilly said, investing 1.5 hours a week over a 26-week grazing season to measure 108 acres of pasture would cost $30/ha ($12.15/acre).
Using this equation, she said the data in a precision management framework could see a profit increase of $13,117. 41, or approximately a $300/ha increase.
“You could, in theory, be paying yourself $336.34 an hour for the time you spend measuring pasture,” said O’Reilly. “What else on the farm has that kind of return for your time?”
Data has to be applied, not just measured
Measuring alone won’t produce those profits. The data has to be applied to maximize the grazing capacity of each paddock.
Instead of employing a circular rotational grazing system that follows a take-half-leave-half mantra, the grazing wedge is adaptive multi-paddock grazing tool tracking of which paddocks offer the most to the least amount of cover, days worth of grazing and quality against a target-line measurement.
This allows a producer to optimize each paddock, ensuring the cover is grazed before the grass gets too mature or, near the low end where the grass is residual and not considered grazeable.
If the grass goes beyond the target line it can be resourced as baleage or stored forage. If data shows a looming forage deficit, it points to the need for supplemental feeding so the pasture can regenerate.
Grass utilization measurement, which is the difference between where the grass stood before and after the livestock has grazed it, is a strong indicator of grass quality and can drive carrying capacity.
“If our utilization rate is only 55 per cent then we’re stocking just over half a cow per acre,” said O’Reilly. “If our utilization rate is up to 75 per cent we’re looking at .7 cows per acre. It is an appreciable difference and it does really affect the carrying capacity of a farm overall.”
The catch with utilization is that optimizing is not the same is maximizing.
It takes more labour and infrastructure to achieve that so a decrease in ROI is seen when utilization is increased, and producers need help to find the economic sweet spot.
Precision pasture management can help Canadian producers stay competitive in the future, said O’Reilly, but it’s an area that requires more research to make it sing in the agriculture sector.
“It really shows how a better understanding of pasture dynamics, how the pieces fit together and really having quantifiable data of how these plant-animal relationships work can help us improve economics at the farm level and at the sector level,” she said.
“We can be pretty confident we’re leaving money on the table by not exploring this precision pasture management further.”