Moving the mob

Clover Blog

Greg Judy : A Masterclass on Mob Grazing at Groundswell 2018

I was lucky enough to attend the Groundswell no-till and mob-grazing conference 2018 in June, hosted by Lannock Manor Farm in Hertfordshire

This year’s keynote mob-grazing speaker was my grazing guru Greg Judy. Like many farmers trying to avoid the mainstream rhetoric, the source of much of my agricultural influence has come from ideas shared by other farmers on the internet. When I discovered Greg Judy on YouTube, it consolidated a lot of half-baked notions into a system of grazing that made complete sense to me. I had experimented with a systematic, regimented form of high-density rotational grazing with some success but an ultimate failure as nature thrives in chaos, not a regime. Greg Judy introduced me to the idea of holistic management – to graze with the flexibility to respond to changes in the weather and seasons and to make decisions considering everything from the soil, the animals, the grass and the broader ecosystem. What drew me most to Greg Judy was that he had learned to do all of this based on some simple “daily monitoring of livestock and pasture conditions.”

Greg Judy and Clive Bright
Greg Judy and Clive Bright

Greg farms in Missouri in the US. Like many innovators, times of crisis lead him to question the status quo and find a different way to make things work. He started farming by borrowing heavily to buy land, animals and machinery. After some bad years, in 1999, on the brink of bankruptcy, he lost some of his lands and was forced to sell his animals and machinery. Determined to recover, he started mob-grazing by contract, rearing other people’s animals. Noticing the positive effect of mob-grazing on the farm, he realised he could use the animals to improve degraded properties that were very cheap to rent in his locality. The farmers who owned the cattle also provided winter fodder/hay for their animals. So with minimal investment in fencing and watering infrastructure, Greg was getting paid to graze other people’s cattle on other people’s lands, and they provided all the fodder which he ‘bale-grazed’; that is, rather than housing the animals, he rolled out the hay on the degraded land. The animals ate most of the rolled out hay but trampled and dirtied the rest – this added organic matter, dung and a seed-bank to kick-start the regeneration of these farms. This land then grew more grass and Greg could carry more animals, and before long he was making good profits. He now manages 16 farms (four of which he has bought and paid for) totalling 1600 acres. He now owns all his cattle, a herd of around 340 South Poll cattle from which he breeds and finishes 100% grass-fed beef. Greg’s first book called “No Risk Ranching” tells this story as well as sharing the wealth of grazing knowledge he accumulated from the experience.

“Get ruminant animals back on the land, harvesting solar energy and converting it into dollars with little or no-costs”

Animals vs Diesel

Greg runs his operation without a tractor, using only an ATV to manage his 1600 acres. He does not house his animals or bale hay/silage; instead, he out-winters his animals at a low stocking rate on stockpiled standing grass. If you think about a herd of ruminant animals – the potential disturbance of all those hooves, the inoculating rumen and nutrient cycling of their guts, and the mowing action of their mouths – in a mob they become a powerful tool. Rather than machinery Greg advises to “invest in fence, water and livestock.”

The best way to explain mob-grazing is to compartmentalise it. There are three principal elements, the soil, the grass and the livestock. Other auxiliary considerations are wildlife, the broader ecosystem, the topography and soils type and water sources. However, for this article, we focus on the main three as they are the main drivers of profit and production.

The goal of mob-grazing is to use the relatively tightly mobbed herd of animals to trample some grass into the soil as litter, creating organic matter to feed the soil biology. The added organic matter increases nutrient cycling, fertility and soil structure, all while feeding the animals and managing the grass in a manner which allows it to grow and photosynthesise to its full potential. The top third has all the energy and sugar and the livestock thrive on it. The rest has the potential to feed the soil in the form of litter or photosynthesise to grow more grass faster.

“The general rule is to graze a third, trample a third, and leave the last third standing”

The herd are rotated around the farm in small but flexible paddocks that gives them an allocated area for a short period. If the ‘third – third – third’ rule is followed throughout the growing season and the grass is fully recovered before the herd return to the first paddock, on each rotation of the farm the grass should be getting longer and longer, building a winter stockpile as you go.

“Trampled grass is not wasted grass”

Greg proclaims that “we have got to get more trampled litter on the ground. For every grass stem that is trampled, it grows two more. Think of it as a savings account – it is building soil, building carbon”. In a short time, this increases overall grass volume as the soil quality improves. Like most farmers, he was taught that animals stay in the paddock until all the grass is eaten; otherwise, it is wasted. Now he testifies that leaving grass behind is a good thing, not a bad thing.

Grazing heavy cover
Grazing heavy cover

What size should the paddocks be and how often should the animals be moved?

Mastering the ever-changing answer to the paddock size question is the art of mob-grazing. Judging paddock size involves constant observation and adjustment and is dependent on the grass cover, the season, the weather, and the type of land. Flexible paddocks are created by dividing fields up with a temporary electric fence and typically a mobile water trough. (There are also strategies using static water points like wheel spoke paddocks or by creating laneways).

“If the grass is growing fast then move the herd fast; graze the top of the plants and move them quickly”. This top-pruning keeps the grass from going to seed while building up the bank of grass. If the grass is growing slowly (during a drought, a cold snap or in winter) that bank of grass can be utilised and the rotation should be slowed down. There are two factors to manage the speed of rotation, one is paddock size, and the other is the time they are in that paddock.

If the paddocks are too big, there is not enough mob pressure, and the animals spread out and selectively graze the sweeter grasses and leave areas other ungrazed. Little or no trampling will be achieved and unless the farm is vastly understocked the grass will not have recovered before the animals are back again. This will cause over-grazing and weakening of the sweeter grasses and will allow the rougher grasses to dominate and eventually, the pasture will diminish in diversity and quality.

If the paddocks are too small and the moves are not frequent enough the animals will graze it too tight. This will mean there is no organic matter being trampled on the ground and the grass plants will take longer to recover from the hard grazing event. The animals’ growth will be limited by forcing them to eat too much low quality and fouled grass. Tight grazing also increases the risk for clinical parasite burdens. The threshold is narrow for misjudging the paddock size, creating a high risk of underfeeding and limiting the animals' growth potential.

Another observational indicator is “if the manure pats get too runny, that is a red flag to increase our paddock size which effects animal selection. Runny pats are an indicator that the cows are grazing too low. They are limited in their selection of quality plants. Keep them on the top portions of the plants and the manure pats will be the consistency of a pumpkin pie. The manure pat should have wrinkled swirls building up the sides of the pat. For a nice finishing touch, the pat needs a small indent in the middle of it.”

The trick with paddock size is to find the sweet spot. The decision of how often to move animals often comes down to a lifestyle choice, the more frequent, the better, but it takes time, and advantages need to be weighed up. Greg moves his herd 3-4 times a day. Once a day is very effective but reasonable results can be achieved moving them every two to three days (three days is the maximum*). I have found twice daily moves are achievable and give you excellent control and great results, but for lifestyle reasons, I currently move once daily. With movement times being fixed, paddock size is now the main variable to achieve desired results.

*Three days is considered the maximum that animals should have access to an area. After more than three days there is a risk of re-grazing recovering plants which will weaken those plants.

The paddock size is be adjusted daily by monitoring the amount and consistency of trampling, the amount of grass left behind and the gut fill of the animals. During times of fast grass growth, all these factors should be pushed to full potential. The correct paddock size will result in relatively even grazing of the top third of the grass, together with trampling and a good scattering of dung. A rough indicator of the correct density is if, while walking a random transect of the field you come across a fresh cowpat every 10 paces. In five or six rotations over a couple of years, the whole farm will have had a covering of cow-pats. It is estimated that it could take as long as 27 years to achieve the same coverage with continuous set-grazing.

During times of slow grass growth or dormancy, the principal aim is that the animals are well fed, so watch for gut fill. Ensuring your animals are full is done by observing the triangular indent on their left side in front of the hip bone. A good rule is to try and leave enough grass for one more day, it is a buffer in case of emergency but also, leaves cover and protection for the soil, and when grass does start growing again, it will recover much quicker.

Another thing to watch for is that the animals are not forced to reach under the electric fence to find food; if this is the case the paddock is too small. It is essential to continually observe, respond daily to changes and adjust management accordingly. For example, if there is a heavy rainfall event, it is wise to increase paddock size to relieve the stress on the ground and minimise damage to the pasture.

The shape of the paddock and where the water source is placed will also have an effect on the grazing outcome. In a square paddock, the herd will utilise more forage, while in a long, narrow paddock the animals will trample more litter on the ground.

Recovered Grass

The grass needs to, at the very least, have a point on the tips of the blades before it is re-grazed and ideally the most desirable grass species should have three/four leaves. At this stage, the grass plant is deemed ‘fully recovered’ which botanically means it has replenished its root reserves and is still in a vegetative or growing state (not going to seed).

“It is crucial to success in mob-grazing that the grass has fully recovered before re-grazing”

The rotation length in a growing season is dictated by the speed of recovery of the grass. If the rotation is moving faster than the recovery time it is a good indication you are over-stocked. This can happen because of a poor growth year due to drought or low temperatures or persistent rainfall. Greg advises that you should always have the worst 10% of your herd selected in case of a need to de-stock quickly. “The earlier you sell them, the less you will have to sell or the less feed you will have to buy”. He says “grazing unrecovered grass is the quickest way to go broke in the cattle business.”

On the plus side, practising mob-grazing speeds up grass recovery and makes pastures very resilient to unfavourable weather, because the soil is covered and there is always a mass of photosynthesising leaves. With continued monitoring, the potential to increase stocking rates is more likely.

If it is the case that you are understocked, or it is a particularly good growth year, and the grass ‘gets ahead of you’ (goes to seed) the conventional wisdom is to bale these paddocks to shorten the rotation and save fodder for winter. Greg does not bale any of his grass, considering it a waste of money and fertility. Instead, he leaves the grass that has gone to seed standing as a reserve to be grazed in times of drought or hard weather and shortens the rotation in this way, keeping the herd grazing vegetative recovered grass.

Greg buys all the hay he uses. He keeps it in storage in case of emergency. It is his only input, and he looks at it as buying fertility. The hay bales are rolled out in the field, during periods of heavy snow or prolonged freezing when the cows are struggling to access their forage or lack a dry place to lie. He also bale-grazes poorly degraded land as a measure to revitalise it - by adding organic matter, dung and seed (from the hay).

Suitable/Adapted animals for the surroundings and the management

Greg advocates that ruminant animals are “herbivores not granivores” but also says that not all cattle are suited to mob-grazing a 100% grass-based diet or the forage on a particular farm. Greg’s pastures were predominantly fescue (a low feed quality grass with toxins and high tannin). By mob-grazing, he has increased diversity in his pastures, but fescue remains present in high percentage. Therefore it is important for his profitability that his animals can utilise and thrive on fescue. He has South Poll cattle – they are a low maintenance, medium-sized, polled breed that is suited to his farms. Animals that are not thriving are simply culled: Greg refuses to prop up animals that are not performing and says “by culling those animals, before long, you end up with a herd of animals that are adapted to your farm and your forages.”

Animals shedding their winter coat is a key observational marker: “animals that have not shed-down by early June, are not processing the forage on your farm and are not adapted to your farm.” Of course, it should be noted that failure to shed could be caused by other stresses such as a parasite burden.


Greg states that 80% of a cattle farmer’s costs are related to the winter housing period. By only grazing 1/3 of the grass on every rotation, the bank of standing grass grows throughout the grazing season. Extending the grazing period is key to profitability. Greg carries small-framed animals at a relatively low stocking rate and out-winters with no sheds: he also never makes hay, but does buy enough for the worst case scenario.

Fescue, the predominate grass on his farms, loses its toxicity in the winter and it makes excellent winter grazing because it remains standing and has a dense root mass which holds up well to hooves in wet weather. Greg says with the right sized animal (900 – 1100 lbs) rotating on stockpiled grass or standing hay we “let the animals harvest it, and spread the manure all in one go.” It takes the work and cost out of winter.

Spring Grazing

It is vital that grass has fully recovered after winter dormancy before it is eaten in spring. Grazing young plants in spring causes enormous stress on the plant. Stress causes the plant to go to seed and reduces forage quality and quantity by up to 40% of the potential annual grass growth. A plant that is not stressed will grow more leaf and build energy reserves before it goes to seed and is more productive throughout the season.

The spring flush grass is all protein with very little energy/carbohydrate. This grass runs though animals and when they have very runny manure, some farmers feed hay or straw to compensate. Greg aims to have the first grazing of spring growth coming up through the last of his winter-stockpile, so the dry matter balances their rumen and they don’t get an upset gut in the springtime.

Using the mob as a tool

Having control over a calm, responsive herd of animals allows you to use them to perform functions:

  • Clearing rough pasture and scrubby growth, grazing areas inaccessible to machinery, tramping and breaking down a thatch;
  • Reseeding - the main factor of reseeding which dictates its success is good soil contact. Soil contact is generally achieved by rolling, but it can be equally or more successfully achieved with herd impact;
  • Exclusion zone – this term refers to an area of a paddock wherein you tighten up the animals into a very small area for a short time. It can vary; to standing room only for half an hour or a similar density to winter housing for an overnight period. This change of animal impact is generally used to alter the plant species in that area and therefore increase diversity – it will commonly encourage clovers to dominate in that area. The high impact allows seeds of different grasses and plants that were lying dormant in the soil to express themselves. You can witness this phenomenon on your farm by observing the change in flora around gateways and other areas of high impact.
Exclusion zone
Exclusion zone

To summarise the daily monitoring of livestock and pasture conditions

The basic rules are:

  • Never graze grass that hasn’t recovered, make sure your animals are always full without over-grazing and aim to trample litter on the ground;
  • Gut Fill - cattle leaving the paddock should have their rumens full. If the gut is not full, that animal is being limited and not gaining to their full potential;
Gut fill image
Gut fill image
  • Recovered grass is grass that has regrown a point and has reached the three to four-leaf stage;
  • Top Third – aim to graze only the tops of the plants, this allows for speedy recovery, increased growth and resilience to adverse weather conditions. It slows the drying of soil and buffers heavy rainfall;
  • Litter – protects the soil from sun and rain, feeds soil biology while building soil organic matter, fertility and structure.

The reason for practising mob grazing is to get a high level of production with minimal inputs while improving soil and pasture diversity. It allows livestock to thrive and be a constructive element within the farm ecosystem. It is a low-cost, resilient system that anyone can put into practice once the fundamental goals are understood.

Greg’s Drought Advice Missouri has had severe droughts and generally has seasonal summer dormancy. Drought was topical at Groundswell as the event happened during the height of this summer’s drought. His experience yields valuable advice: “By focusing on growing taller plants in the early spring before grazing them, you will be able to endure a drought. Armed with this stronger forage base, you must monitor your stocking rate at the first hint of drought. Act early and get rid of any animals that can be marketed. Focus on leaving as much forage as possible in each grazing pass to protect your soils. It will rain again, and when it does, your farm will catch and hold the water. You will be rewarded with faster grass re-growth from dormancy simply because you did not graze off the pastures to a parking lot.”