You may have heard the advice, over and over again, to allow your pasture grasses to reach 6-8 inches in height before you let your horses graze. And then you’re also advised to pull them off when those grasses are 3-4 inches high.
You may be wondering, WHO does that?? As I drive around the horse properties in my area, I can tell you: Not too many! This is more the typical grazing pattern you see around here in this rainy climate where land has shot up in the last five years to $1 million per acre:
So I have never understood how the rotational grazing advice actually works, or is even possible, unless you have 20 acres or more… UNTIL I watched this video! And then the giant A-ha clicked into place.
Like me, you may have been wondering: Okay, so I can let the grass grow to 6 inches at the start of the grazing season (when the ground is dry enough that the hooves don’t destroy the root system), but if I pull them off after they’ve grazed only 2 inches worth… and put them on another patch… then the first patch is NOT going to have time to re-grow to 6-8 inches before I need to put them back on there… so??
But as this video shows us, the KEY element is that grasses with a 6 inch root length (what you see above ground is also below ground) and 4 inches of stem (aka flowering leaf) can re-grow 3-4 inches in only five days!
According to Krista Lea from the UK’s Department of Plant and Soil Sciences:
“Grasses absorb sunlight in their leaves and produce energy from photosynthesis. This energy is then used for growth or stored in the roots as carbohydrates. When grass is grazed (or mowed), leaves are removed, reducing the amount of light the plant can absorb and energy it can produce. To recover, grasses use carbohydrates from the roots to regrow their leaves. But this comes at a price: Roots will physically shrink as these carbohydrate reserves are used up. Once the leaves are able to absorb adequate sunlight for photosynthesis, the root reserves are replenished. This is a normal process and allows grasses to recover from grazing and thrive.”
So the reason the grass can grow so fast when it’s longer (4-6 inches) is because the longer the grass, the more energy it can pull (via photosynthesis) to fuel rapid growth. Et voila!
The reason long grasses contain less sugar is because the plant is not stressed, and so is not pulling carbohydrates (sugar) from the roots, to fuel it’s growth. The other aspect that creates higher sugar levels in grass is drought. Again, lack of water stresses the plant and thus increases the carbohydrate/sugar requirement. So if sugar is a big concern, then make sure you can irrigate your pastures in case of drought. And of course, don’t let your grass height fall below 4 inches. As Krista Lea says:
“The bottom line is that healthy pastures need healthy roots. Think of the soil surface as a mirror: whatever you see above the ground is also what’s below. Pastures with tall, thick grasses will also have thick, healthy roots. These will hold the soil down during heavy rainfall, withstand hoof and tractor traffic better, and survive longer in droughts. Conversely, thin, short, overgrazed pastures will have shallow, sparse roots and will be more vulnerable to traffic, drought, and grazing.”
The key here is to ideally have 3 pastures for rotational grazing. Or you can put them in your ‘sacrifice field’ or dry lot area and hay feed for a couple days in between if you need to.
Seeding a trashed field
Here’s another piece of advice you’ve probably heard over and over if you live in a rainy climate: Confine your horses to a dry area, or small sacrifice field over the wet months, or they will destroy the root system and your pastures will have no grass left in the Spring/Summer.
And when they say “destroy”, they’re not kidding:
Again, I understand the logic behind this advice. BUT. Following that advice also means my horses will have nowhere to run, play, wrestle for 7 months of the year! And I personally LOVE to see them thundering over the fields – it’s one of my favorite things.
So… I let them trash their main pasture. It wasn’t too bad the first year, but the second year (see pic above) it was pure mud in the winter and was going to be a dust bowl in the summer. So we electric-fenced off most of it, leaving them a walking track around the outside perimeter.
I had no idea about soil pH, fertilization materials or rate, or even which forage grasses would grow well in this climate, and on this soil. After doing reams of research I was even more afraid and started looking for a consultant to hire.
Then something in me started to rebel against it all being so darn precious. C’mon, grasses have been seeding and sprouting themselves for millennia without the help of humans! How hard can it be??
The year before I had bought a 60 lb bag of ‘horse and sheep’ grass/forage mix from the feedstore and just scattered it over the pasture – without fencing it off – to see if that would work. Nope. Total waste of $180.
So this year, we spread a pasture forage mix inside the fenced-off area only – avoiding the places that were flooded with water (too much water and the seeds will rot) and feeling for the right time to sow… the time where rains had just finished and we would get some good sun to help the seeds sprout before the rains hit again. Total nail-biting crapshoot, right? Lord, I don’t know how farmers do it – worse than gambling in Vegas if you ask me.
Well amazingly, we hit it just right: We hand-spread the seed a day after the rains stopped, then we got 5 days of solid sun, it rained again for 2 days, then 2 more days of sun, et voila:
Note: This year I have a friend who studied Horticulture in college and he told me to seed in mid-April when the overnight temperatures should get up to 7 degrees Celsius (or higher) as this will encourage fast germination. Great advice. The other thing I changed this year was to add 1/4-1/2 inch of composted horse manure with live worms first, then I sprinkled the forage seed. I followed Will Harris’ advice and seeded at 15 lbs per acre. If you want to be really rigorous, walk all over the seeds after sprinkling to press them down into the soil. This worked brilliantly!
Every week or so, we checked to see how things were growing…
By the time the grass hit this height, the horses would stand at the electric fence, waiting… begging to be let in:
And now that I finally understand how quickly grass can regenerate if left longer than 4 inches, I definitely will not let the horses on here until this new pasture hits 6-7 inches high. Unless of course they get fed up with waiting and mow down the electric fence – which is always a possibility with my crew. Fingers crossed!
Luckily I had also been able to fence a new pasture for them at the back – which is in great shape. So as soon as the ground hardened (by which time the forage back there was tall enough) I opened up the gate to the back pasture as well. But thankfully, they did not get destructive with the electric fence in this field and the grass looked like this when I finally let them in for the first time – note the contrast with the plain dirt which was not seeded!
In some areas of the field, the grass is extra high and lush:
WELL WORTH the extra effort, wouldn’t you say? And so much nicer to see horses galloping across a field of green, rather than a dirt dust bowl.