(The following is from my monthly newsletter. This series began in March 2022 and has continued for nearly a full year, with its final installment in February 2023. Below is the “better” edited version from what I originally emailed to my followers.)

This time we switch gears and look at Grazing Tools. The first tool we’ll look at is Time. We use community dynamics to build biology, influence the presence of desirable and undesirable biological organisms, and better understand how ecology functions.

Time in Growth and Yield

Plants take time to grow, like any living thing. They reach a certain point in time where it’s best to graze them for optimum quality and optimum yield. They also reach a time when it’s “too late” to graze (not really, it’s all in context; sometimes it’s good to leave certain areas to graze later in the year when plants are dormant) because they’ve reached maturity and have set seed. Their roots also take time to grow, reaching a point where they can start to store energy and divert resources to soil microbes instead of sacrificing themselves to grow leaves.

They grow in an S-curve, where the first phase is where the plant switches from taking energy from the roots to grow new leaves to generating energy from the leaves via photosynthesis. The second phase is very quick, as the inflorescence (seed-head) is close to emergence. Once the seed head emerges and begins flowering, phase 3 has started, where yield is maximized, but quality declines the more the plant matures.

Time affects quality and yield (as do other factors including soil fertility and precipitation). This is where determining when is the best time to start grazing and when to return to the paddock or pastures that have previously been grazed is important. The target should be what is considered “optimum” which is typically at phase two (or stage two, above) growth phase. Plants are deemed “ready” at that stage because not only is the top growth showing it’s ready, but the roots are fully recovered as well.

Roots are crucial for grazing. They ultimately how mismanagement can negatively impact the pasture stand. Roots also need time because, the plant, post-grazing, is forced back to early or late square one (or stage/phase one) where energy must be brought up from below ground to start growing new leaves. As a result, a bit of the root material sloughs off.

What sloughs off must be regrown; as above, so below. During this regrowth process, the plant is most vulnerable to being re-grazed because roots are trying to return to what they were prior to grazing. Should they be grazed at a point when plants aren’t ready yet, more root material is sloughed off leaving even less than before. This means plants will either need even more time to recover, or they will end up being stunted and pasture yield compromised. (This isn’t as noticeable right away; often it takes a few years of repeated overgrazing to see the results.)

Of course, just how much is removed is also time-dependent (see graph below). The more that is taken, the longer plants need to recover.

Also, the less that is taken, the shorter time is needed for plants to recover. And, the later plants are grazed, combined with taking less than half of the present biomass, the less time is also needed for plants to recover.

But, that’s the thing: Time is needed for plants to recover. This is absolutely crucial in both maintaining the integrity of the stand, and its longevity. If plants are not given this adequate time period to recover, they slowly die out. This lack of recovery time is called overgrazing.

Defining Overgrazing

I’ve heard multiple definitions of overgrazing, from having too many animals on the land (which is widely accepted yet completely wrong), to it being a concept of time where the plants, due to management, are not given enough time to recover. The best and most concise definition I’ve found to date is that overgrazing is simply the grazing of the roots.

Severely grazed plants are set right back to square one. They need to divert their energy source to the roots and crowns in order to grow new leaves. Normally a plant’s primary energy source is in the leaves, but because those leaves are gone, the energy that has been stored in roots or used to grow new roots must be diverted to grow new leaves.

Once the leaf material has been replenished, the plant can go right back to focusing on regrowing those lost, dead, sacrificed roots.

Thus, when overgrazing, it’s “grazing of the roots” because animals are permitted to come back and eat the plant that is in the process of recovery, sacrificing even more roots than before. The image below shows a study that was done by clipping plants at different times in order to see what happens to the roots. The results are, unsurprisingly, astounding.

Here are just three ways how you can overgraze your pastures:

1. Stay too long,
2. Return too soon, or
3. Start too soon after dormancy has ended.

I do wish there was a nice recipe everyone could follow for how long is too long for animals to graze and when animals can come back after an area has been left to recover. But, there isn’t. It all depends on, as we discussed previously, how much your animals ate and trampled in that stand; the less they took, the sooner they can return.

What about Too Much Rest?

Total or partial rest is equally as bad as, if not worse than, overgrazing. In arid, brittle-tending environments, too much rest means plants are not provided with the necessary disturbance to remove dead material. Grasses cannot shed leaves like trees can, which is where ruminants come in to help with that.

If nothing is there to help trample, eat, or somehow remove some or most of that leaf material, it shades out the base of the plant, preventing moisture from seeping down (or from escaping), impeding tiller growth, and slowly suffocating the plant to death. The material doesn’t quickly decompose; much of it will oxidate and turn grey, remaining on the rest of the living plant.

The dead material that does slough off with mechanical disturbance like heavy rain or hail washes away, revealing soil, and exposing the soil to erosion. The more plants die, the more leaf material gets washed away, the more soil is exposed and the more erodes away.

Partial rest is a term that came from Allan Savory to describe land that didn’t receive sufficient disturbance by grazing herbivores. They pick the areas they want to eat and over-utilize and leave the rest alone (a.k.a., continuous grazing). Total rest is the complete absence of any grazing herbivore for a long period of time (i.e., over 5 to 10 years, over 20 years, or longer).

Time plays a big role because the longer these areas and those plants experience rest, the more plants die and the more degradation occurs. Areas that are less brittle-tending (or tending towards non-brittle) have less of such issues, but plant material still can build up over time which impedes plant growth, despite some decomposition processes happening.

Other Timely Factors for Good Grazing

I didn’t mention seasonal growing periods. Springtime is typically the time of year when plants are growing the fastest, and when moves must be timely and quick (but not too quick) to keep up with the growth rate of the spring flush. In other words: Grow fast, graze fast.

In the summer, plants are slowing down growth rates as compared with the spring flush. Hotter days, and less rain in the forecast (usually) slow plant growth. Therefore, grow slow, graze slow. But not too slow!

Another million-dollar question every single grazer seems to have a different answer to (lol): How do you tell when a pasture is ready to graze again?

The answer is, sadly, it depends. It depends on what your goals are, and your context. That said, probably the best answer I’ve heard so far is from Greg Judy who has observed that, if all the leaves on the grass plants have those pointed tips (as opposed to blunt tips that are a result of sheering from grazing [or mowing]), the pasture is ready to graze. I might add too that, when the flowering heads are just about to emerge (or starting to emerge), it’s time to turn the animals in.

In the end, it’s still, “it depends.”

Because, how long you graze will depend on how long you must rest your pastures or paddocks. The vice versa of this is also true.

Key takeaway: The longer they stay, the more they take. The longer they stay, the more time that area needs to recover.

It’s one thing to severely graze a pasture. Severe grazing, by and large, is not a bad thing. But overgrazing, or grazing of the roots, is quite another and should be avoided as much as possible.

In grazing, growing, harvesting sunlight, and moving on, Time is always of the essence.