Managed grazing

What managed grazing is

A herd left on the same pasture all season eats like a child in a sweet shop. It goes back again and again to the plants it likes best and bites them before they have recovered, while coarse and bitter plants spread. Managed grazing breaks this habit. The land is divided into smaller areas, called paddocks; the animals graze one of them for a short time and then move on, and the grazed paddock rests until it has regrown. Grazing and rest become two halves of one plan.

The idea was set out most clearly in the 1950s by the French farmer and biochemist André Voisin, who called it rational grazing. His first two rules concern the plants: grass needs enough rest between two grazings to rebuild the reserves in its roots, and the animals should leave a paddock before they start biting the regrowth that appeared after they arrived. His other two rules concern the animals: those with the highest needs get the best forage, and short stays give steadier results than long ones. Later approaches such as adaptive, mob or holistic planned grazing build on the same core and differ mainly in how densely the animals are stocked and how the plan is adapted.

In permaculture terms, grazing animals are elements with many functions. They turn plants people cannot eat into milk, meat, wool and dung, they trample dry litter into contact with the soil, they spread nutrients and seeds, and they keep grass and shrubs short. Whether these functions help the land or harm it depends almost entirely on how long the animals stay, how many there are and when they return.

What it does in the system

A grass plant that loses its leaves draws on its root reserves to grow new ones. If it is bitten again too soon, the reserves shrink, the roots retreat and the plant weakens. Rest lets it rebuild, and a rested pasture keeps more living cover, which protects the soil against heat, wind and heavy rain. Short, intense grazing followed by rest also spreads dung more evenly than a herd that gathers under the same trees every day.

The research is more sober than many promises. In 2008 Briske and colleagues reviewed grazing experiments on rangelands and found that rotational systems did not consistently produce more plants or more animal growth than continuous grazing; the number of animals and the weather mattered more. Hawkins reached a similar conclusion in 2017 for holistic planned grazing. Supporters reply that fixed experimental rotations cannot test a manager who adapts to every season. The honest summary is that managed grazing is a tool for control and observation, not a recipe. It works where someone watches the plants and adjusts the number of animals.

How to begin, step by step

1. Observe a full year. Note when the plants grow, when they stop and which ones the animals prefer. In a Mediterranean climate, growth starts with the autumn rain, peaks in spring and stops in the summer drought.
2. Set the number of animals first. Plan for the leanest season, not the best one. Too many animals cannot be fixed by any rotation.
3. Divide the land. Movable electric fencing makes it possible to try paddock sizes before anything permanent is built. Every paddock needs access to water and, in hot climates, to shade.
4. Let the rest period set the plan. A simple rule of thumb from the US National Center for Appropriate Technology: the number of paddocks equals the rest period divided by the days spent in each paddock, plus one. With 30 days of rest and 3 days of grazing, that makes 11 paddocks.
5. Move by looking, not by the calendar. Leave enough leaf behind for the plants to regrow, and move before the animals bite the fresh shoots.
6. Protect young trees. Goats browse bark and shoots readily, sheep and cattle bite what they can reach. Keep animals out of new plantings or guard each tree until it has grown out of reach.
7. Keep notes. Dates, paddocks, number of animals and the state of the plants show within a few seasons what the land can carry.

An example from the Mediterranean

In Andalusia the regional government has paid shepherds since 2005 to keep firebreaks in public forests grazed. The Red de Áreas Pasto-Cortafuegos, known as RAPCA, contracts herders whose sheep and goats graze the strips most intensively in spring and early summer, before the fire season. Field staff check whether the targets for grass and shrub were met, and payment depends on the result. A study by Varela and colleagues in 2018 counted about 220 shepherds maintaining almost 6,000 hectares of fuel breaks and judged the scheme more efficient than clearing by machine. In Sardinia, a modelling study from the University of Sassari found that forest grazing reduced the simulated extent of fire markedly, by different amounts in wet, average and dry years. Here grazing becomes part of the fire sector of a whole landscape.

Common mistakes

• Trusting the rotation instead of the count. A well-planned rotation with too many animals still degrades the land.
• Grazing through the drought. Plants that have stopped growing cannot recover. Animals left on dry pasture in summer strip the last cover and expose the soil to the first heavy rain.
• Grazing wet ground. Hooves on waterlogged soil cause soil compaction and open the way to soil erosion.
• Water and shade in one place. Animals gather where they drink and rest. If that place never changes, it becomes bare.
• Forgetting the young trees. A single afternoon of goats in a new planting can undo years of work.

Further in the TerraWiki

• Silvopasture joins trees, forage and grazing animals, the setting in which managed grazing matters most in Sardinia.
• Agroforestry places grazing among the other ways of growing trees with crops and animals.
• Permaculture zones put pasture in zones 3 and 4, and sectors show where grazing can help against fire.
• Element analysis lists what an animal needs and gives, and chickens in the system shows the same idea on a small scale.
• Apply self-regulation and accept feedback is the principle behind adjusting the herd to the land, and desertification shows what happens when nobody does.

On Sa Medada

The land register shows the grazing heritage of Sa Medada: just under 2,000 of its 18,725 square metres are recorded as pascolo arborato, wooded pasture, and the rest as olive grove. The silvopasture article tells that story. The dry season there lasts roughly from May to September, the months in which, anywhere on such a slope, pasture stops growing. This page describes a tool; it does not report a practice on the land.