Do you want to grow more forage, retain more water, sequester carbon, improve habitat, have healthier animals, and improve your bottom line? If you answered no to any of these questions, perhaps you should reconsider being a livestock farmer. But assuming you answered a resounding “YES!” to all of these questions, there is one management technique that accomplishes all of those objectives.That technique is known as adaptive multi-paddock (AMP) grazing, and long term research like this shows that it is successful.
AMP grazing works by mimicking the natural grazing patterns of herbivores like bison, who move across the landscape in dense herds, but remain on any individual piece of land for a very short time. Since the open prairie that the bison traditionally migrated across no longer exists in all practicality, it is up to us to replicate that pattern on a smaller scale on our own properties. This is typically done by using portable electric fences to create small paddocks with the right amount of forage available in that paddock for one day’s worth of grazing.
This is where a lot of producers get stuck. They either have trouble visualizing how to set up a system that is efficient in terms of labor requirements, and that allows the livestock access to water and shade; or, most often, they don’t know how large or small to make an appropriate sized paddock based on their forage supply and the needs of their herd.
Thankfully, OPN has created a revolutionary new tool to address the paddock size question.
You may recall our last blog post about our chicken profitability calculator, this grazing calculator lives at the same link, just click the button below, and then click in the upper right corner on the “Stock Density” link to access it.
Next, you will tell it if you are grazing one single class of animal, or a mixed herd. For example, if you only have stocker cattle, you can click the single class option, but if you have stockers and lactating cows in the same herd, or dry cows and lactating cows, sheep and stockers, etc; click the “mixed herd” option.
Once you have made that selection, you need to go out and take a look at your grass and measure the average height with a forage stick (you may be able to get one of these for free from your local soil and water conservation district or NRCS office) and estimate the density of forage. For the latter, look straight down onto the forage and estimate how much bare ground you can see. Is it less than 5%, between 5 and 10%, or more than 10%? The calculator will use this information to estimate the amount of dry matter available.
Then you will enter information about your herd, specifically the number and average weight per class. It will then calculate the total weight of your herd and the amount of dry matter the entire herd needs per day.
Below that, is your forage utilization goal. You’ve probably heard the adage, “take half, leave half,” and that is generally good advice. This means that the animals are eating 50% of the available forage, and mostly trampling the rest. Based on that, the default here is set at 50%. There may be times where you want to do more than that, you may want an extremely high density to try to eradicate undesirable plants. You may set it at 70 or 80% in that scenario. Or, it’s springtime and the grass is growing so fast, you may want to encourage just one or two bites on each plant, so you can move through all your paddocks in a compressed time frame. That might require a setting of 20-30%. But, in most cases, it’s fine to leave it at 50%.
Lastly, you’ll enter specific information about your layout on your farm. Do you have a system where you know the length of one side of your paddocks? If so, you can enter that information, and then determine how often you want to move your animals. The default is once per day, but you can move the slider to range from once every 7 days, to 4 times per day.
All of that information will be used to calculate an appropriate daily paddock size, how much forage is available, stocking density, paddock dimensions, and paddock sizes if you select anything other than one move per day.
There are a couple of limitations to this tool to be aware of. First, the forage density analysis is subjective – some grazing sticks have a density estimator on them, but not all. So if it looks like your animals are eating more or less than your utilization goal, maybe get a second opinion on your density analysis. Second, this doesn’t take into account the quality or type of your forage. A lush, legume-rich pasture in May will obviously provide different nutrition than dry, seedy grass in August. Again, observe your animals’ eating habits and make adjustments as necessary. This tool is just a starting point.
However, we are applying for grant funding to do a project with Oregon State University to integrate this calculator with their satellite-based forage measurement system. This would take the guesswork out of forage measurements and use real-time satellite data to provide accurate grazing recommendations. If the grant is approved, it will be a multi-year data collection process, with the final product available in 2029. We will keep you informed on the progress.
