I don't know about you, but I can't ever recall cattle people asking, "So, what's your stocking rate on that section of grass?"
My question is, why not?
Many boast about the size of calves weaned, the number of round bales cut off a meadow, yield of wheat or bean or corn crops, even sometimes how much money they lost feeding cattle. Why not talk about stocking rates?
Perhaps the dearth of discussion on this topic is because many folks consider stocking rate a mystical and unassailable affair. History tells us we've been in a long, slow decline on stocking rate on every continent for a time that's essentially -- well, the duration of history. The prevailing wisdom seems to be we can't improve stocking rate any more than we can improve soil organic matter, so why worry about it? Of course that has been proven wrong on both counts.
But I suspect it runs even deeper, such that many people have little idea what makes up stocking rate or how it's calculated.
I've written before that classic set-stocked stocking rate is calculated upon half of half of the total dry matter produced each year. This was based on the idea that you wanted to take half and leave half, therefore the initial 50% reduction. Then range scientists assume another 50% of available forage will be wasted through trampling, weather or fouling by urine or dung.
The underlying math for calculating stocking rate is really fairly simple (but of course has many variables we can't always account). It is basically the amount of dry matter grown each year on the property in question, matched up with the expected consumption of the livestock on the place. There are some pretty accurate estimates of forage consumption for various livestock classes available on the internet, but a really simple rule of thumb is that a cow eats about 30 pounds per day of dry matter throughout the year. Texas beef specialist Jason Banta explains some of these calculations in a recent column for Hay & Forage Grower.
Along these lines, I had a really fun and enlightening experience with forage sampling and stocking rate calculation a few days ago.
The whole thing began in early summer when I was able to rent by grandparents' old farm from my aunt and uncle and to begin managed grazing it.
Since I've always fussed at people for not taking baseline soil and forage data when they begin adaptive managed grazing, I decided I have no choice but to do it here. I am taking soil samples (more on that later), establishing photo points, and I asked NRCS to provide a baseline forage analysis. That process alone was worth describing.
I've always done forage estimates with a grazing stick, and have never clipped and weighed them. Ted Alexander at Sun City, Kansas, told me once he wore out two or three microwaves drying clipped forage samples to get good at estimating forage. I don't claim that level of expertise.
Here's a short description how our state grazing land specialist for Oklahoma, Brandon Reavis, did the analysis:
He chose two lines that traversed a fairly representative sample of soil type and history. He then threw a flexible range hoop randomly forward along that line. At each landing place, he estimated the top three forage types inside the hoop, which gives a fairly good statistical analysis of the primary plants present. At every other landing place he clipped the forage and weighed it, then converted it to tons per acre. This is generally done for 20 throws and landings of the hoop. At each end he shot a photo with GPS coordinates.
Some interesting descriptions for how this is done can be found at:
This provides me with third-party analysis of forage makeup on the property, as well as two large transect lines. It also relieves me of the necessity to create transect lines of my own.
The data on all this has not come back to me yet, but I'll follow up with you readers when it does.
In future blogs I'll also be discussing how and why we need baseline soil data and what kind we should use.