MEDIC PASTURE

 

Grazing green medic pasture

during autumn, winter and spring

HomeFARMING ZONES IN WANAFarmers' Guide to cereals and pasture > You Are Here

> How do you graze medic? (Training Kit No 3.1)

> Photo guide to grazing - this provides a detailed program of grazing green medic  
 
 

CHAPTER HEADING

SUMMARY OF CONTENTS

The first stage in convincing farmers to adopted medic pasture is to produce a simple budget. This shows the changes in costs and returns when medic is grown and the increase in profit. Some sample budget forms are provided.
If the extremes of over-grazing and under-grazing can be avoided the medic pasture has a much greater chance of success. Some simple planning to provide a rough balance between the area of proposed medic pasture and the number of sheep will make grazing management much more straightforward.
The traditional method of medic pasture establishment in the WANA region over the last 25 years and in Australia for 80 years has been to sow medic seed into a well prepared seedbed. Medic seed can be costly and seedbed preparation and sowing is difficult for small farmers who lack the proper equipment.
Establishing medic pasture using pods is an innovation that offers many potential benefits particularly for small farmers. The method was first developed by ICARDA in Syria in the 1990's and now forms the basis of the Zaghouan rotation in Tunisia. It potential in the WANA region is considerable.
The parcour or rough grazing land occupies more than half of the cereal zone in the WANA region. Pasture establishment using seed has been difficult but pods may be a better option.

YOU ARE HERE

Grazing the green medic pasture is vital in make a profit, to control weeds and produce ample supplies of pods for future years. Farmers in the WANA region have developed innovations that take their grazing management to higher levels of efficiency than those achieved in Australia.
Pods provide a valuable feed supply in summer for sheep and are needed for the regeneration of the pasture in future years. Farmers must find a balance.
Measuring the pods is an important part of grazing management. We have made a separate topic so it can be printed and used as an extension guide for farmers.
The medic pasture has completed its first year. The pasture regenerates with the autumn rains. Farmers must decide whether to cultivate the land for cereals (the classic medic - cereal rotation) or leave it for another year or more. The options are discussed.
Making hay from medic is not as simple as it may seem. This chapter discusses the options and innovative rotations for medic hay production.
Turning the medic pasture into profits is the objective. This chapter shows how live-weights are increased, death rates reduced and lambing percentages increased. The new flock structure is more efficient and produces greater returns.
A check list of possible failures and what to do about them.

 

FOUR COMMON ROTATION ON THE GROUND IN THE WANA REGION

SEASON

ROTATIONS

CEREAL - FALLOW

CEREAL - MEDIC
( Traditional rotation)

CEREAL - VETCH

CEREAL - GRAIN
LEGUME.

AUTUMN

Cereal crop sown

Cereal crop sown

Cereal crop sown

Cereal crop sown

WINTER

Cereal crop grows

Cereal crop grows

Cereal crop grows

Cereal crop grows

SPRING

Cereal crop matures

Cereal crop matures

Cereal crop matures

Cereal crop matures

SUMMER

Cereal crop harvested
Stubble grazed by livestock

Cereal crop harvested
Stubble grazed by livestock

Cereal crop harvested
Stubble grazed by livestock

Cereal crop harvested
Stubble grazed by livestock

AUTUMN

Weeds germinate naturally

Medic regenerates from seed
produced 18 months earlier.
No cultivation of the land required.

Land cultivated and sown to vetch or similar forage legumes.

Land cultivated and sown to grain legume such as lentils or
chick peas.

WINTER

Weeds grazed. Low stocking rate.

Medic pasture grazed. High stocking rate.

Grazed or more often left for hay.

Grain legumes grow.

SPRING

Land cultivated for fallow

Medic grazed. Pods produced for future regeneration.

Cut for hay.

Grain legumes mature.

SUMMER

Bare soil vulnerable to erosion.

Pods and stubble grazed.

Stubble grazed.

Grain legumes harvested.

Stubble grazed.

AUTUMN

Cereal cycle begins again.

Cereal cycle begins again

Cereal cycle begins again

Cereal cycle begins again

Grazing rights in the cereal zone

Our experience throughout the WANA region has been that grazing rights are not a problem in the cereal zone.

The theoretical position is that land not used for cereals or other sown crops is common grazing land that is accessible by other farmers. Medic pasture, particularly medic pasture produced from natural regeneration should fall into this category of common grazing land. In fact that is not so in the cereal zone.

Jordan is a possible exception. Land tenure in Jordan is extremely fragmented. There is more absentee ownership. Farmers often find it difficult to maintain grazing rights over their pasture and exclude other sheep. Even in Jordan these problems can be overcome by community action. For example farmers in the Ma'in district exchanged their rights over their pasture land with other village's rights over their land to allow a pasture development program to be implemented.

In Libya there were problems in excluding sheep from the large government farming projects in the east. This seemed to be associated with the view of the local farmers that the land was theirs and the government had taken it from them. They seemed to recognize each other's right.

In our experience the problem of grazing rights have been exaggerated for two reasons:

Firstly, the invasion of sheep is often and expression of resentment against the government's take over of land or a feeling that the government is wealthy and can share its pastures with poor farmers.

Secondly, the government trial plots or pilot farms are surrounded by thousands of hungry sheep. If pasture development is launch on a large scale there is not the pressure on local farmers to feed their sheep on the government project as they have sufficient feed themselves.

The concept of the quantum leap in pasture production is discussed in relation to the rangeland but the idea can be applied elsewhere.

Grazing rights in the marginal zone

This is the zone between the cereal zone and the rangeland. Grazing rights are more difficult to enforce. They are discussed separately in the section on the Marginal Zone.

Objectives for grazing pasture


Optimum livestock production.

        Grazing medic for optimum production is a totally new concept for farmers in the WANA region. They have experience in grazing weedy fallow.  On weedy fallow the livestock are grazed so they eat all the feed available all the time. This is a sensible strategy as the weedy pasture is cultivated and destroyed in the spring for the cultivated fallow. There is no point in trying to manage the pasture. Rapid and complete exploitation is the optimal strategy.

        With medic the pasture is grazed so the animals and plants are in balance.

    Farmers will need on a day by day basis to balance:-

 The needs of the animals for feed that day.

                  AGAINST

The needs of the plants to grow and produce more feed in future. This is referred to as the photosynthetic factory. The plants also need to produce seed for future regeneration.


 

    The conflict between the needs of the plants and the animals is particularly acute in autumn and early winter.

There is an immediate need for feed for livestock but the medic plants must be allowed to grow to such a size that they can intercept all the sunlight and grow faster in future. Sunlight that falls on bare ground is completely wasted. Sunlight that penetrates a sparse plant cover is partly wasted. The medic must build a photosynthesis factory. Once the plant factory is built the pasture output will be greater.

In spring there is a surplus of growth as the medic plants have grown to a stage where they intercept all the available sunlight. Days are longer. Growth is rapid. Livestock have plenty of feed. The medic pasture benefits from grazing as it reduces the height of grasses and other weeds. The medic is not shaded by these plants and grows more vigorously. 

Weed control.

    Weeds will reduce the quantity and quality of the medic pasture.

They will also produce seed that is carried over to the next cereal crop. Controlling the growth of weeds through grazing is important.

Production of pods.

    In the spring the medic will produce pods.

These are a valuable source of feed for livestock in summer and are essential for the medic to regenerate in future years.

Production of soil nitrogen for cereal crop.

    Medic dominance and grazing are the two important factors for nitrogen production and return to the soil.

They are compatible with the above.

Hay production.

    Medic is not well suited to hay production. It is discussed separately in Hay Production
 

Autumn Grazing  0 to 8 cm.
 

    Need to intercept sunlight.

    The medic or other annual legume pasture will germinate in the autumn after the first rain. The medic seedlings will arrive at this point of germination by:-

    + Having been sown as seed a week or so earlier,

    + Having been sown as pods over a cereal crop in the previous season or,

    + Having regenerate from pods in the ground that were produced from an earlier medic pasture.

    The immediate grazing management objective is to grow a complete cover of the ground as soon as possible.

There are a number of factors that limit pasture growth in winter.

The amount of rainfall, the fertility of the soil, temperature and sunlight are some of the most important. With the short days of winter approaching it is important that the pasture utilise all the sunlight that is available. This can only be achieved by a complete cover of the ground with a pasture about 8 cm high.
   

This objective must have priority over the immediate needs of the livestock.

The livestock are short of feed.

The rest of the arable land on the farm is being cultivated for cereals or other crops.

The parcour should be managed in the same way as the medic pasture.
   

Allowing the medic pasture to grow and cover the ground completely will provide the basic structure - the photosynthetic factory - that will produce much greater output of feed for livestock in future.

    Feeding the livestock.

    The livestock should be fed on hay or other conserved feed. The quality will depend on how close the female sheep are to lambing.

If they are still more than 8 weeks from lambing the sheep can be provided with a low quality hay or medic straw.

Alternatively a treated (with urea) cereal straw or cereal chaff might be used.

If the sheep are closer than 8 weeks to lambing there will need to be a better quality diet. A good hay or some grain supplement.

Feeding sheep in a yard in Jordan. Sheep in the WANA region are kept in yards and sheds over night and fed straw, chaff, grain, hat etc. when pasture is inadequate.

   Length of feeding period.

    It is impossible say precisely how long the livestock should be withheld from the pasture.

The most important factors are the density of seedlings and the rainfall.

If there is a high density of medic seedlings and adequate rainfall grazing will be deferred for only two or three weeks.

If the density of seedlings is poor or if the rainfall is inadequate growth will be slower. It will take longer for a complete plant cover to be achieved. See Photo grazing guide for details.

    Other objectives.

    The objectives such as weed control etc. are all postponed as overwhelming priority is given to building the photosynthetic factory as quickly as possible.

    Measuring the height.

    The height of 8 cm is approximate. It is half a hand.

The pasture will not be uniform - an average must be used.

The objective is complete cover of the ground but there will be some bare patches.

It is not possible to wait for all to be covered.

Different species of medic have different growth habits. The popular snail medics for example have a more erect form and will need 8 cm of height to produce a complete cover while other types have a more creeping form and will cover the ground and intercept all the sunlight when they are less than 8 cm high.
 

Measuring the height of the medic pasture using a hand. There is no need for any greater accuracy.

Winter grazing 8 cm. and steady at 8 cm.

    When the complete interception of sunlight has been achieved the livestock are taken out each day to graze on the medic pasture.

   Over-grazing.

    If the medic pasture has been planned to be in balance with the livestock the pasture over the whole season, it can at this early stage be over-grazed.

This may seem contradictory as the objective of the stocking rate plan (see   Stocking medic ) was to achieve a balance between animals and livestock.

The balance was over a year not just in the winter period when pasture growth is slow. If the livestock and pasture are in balance in the winter then the pasture will be grossly under-grazed in spring.

The livestock (if grazing time is not limited) will eat the pasture growth down (height well below the 8 cm optimum) and the interception of the sunlight will no longer be complete.

Production of feed by the pasture will be lower.

The livestock will obtain a short term benefit from eating the accumulated growth of pasture but once that has been consumed production will be less. The photosynthetic factory will be operating below capacity as a large part has been destroyed.

    * What to do about overgrazing?

    The height of the pasture should be maintained at the same level of about 8 cm.

This is done by controlling the number of hours each day the livestock graze on the pasture.

If the pasture is too short the livestock should be grazed for a shorter period. They should still be grazed daily but for perhaps two hour instead of two hour and an half.

If the pasture is growing taller than the 8 cm level the livestock should be grazed for a longer period each day.

    * Other feed for the livestock.

    The medic pasture at this stage in winter provides small quantities (considerably more than the weedy fallow but not at the level of spring production) of high protein feed.

The livestock should be provided with unlimited quantities of cereal straw overnight and in the yard, fold or sheep shed when they are not grazing the medic.

    The cereal straw has a low protein content and a low digestibility.

Livestock will lose weight on a complete cereal straw diet. If the bacteria in the rumen are fed with a rich protein source such as the green medic pasture they can digest the straw better and more quickly. Intake will increase and the straw becomes a valuable source of energy. The combination of straw and young green medic is an excellent diet. It is important to remember that the mixture must be renewed daily. Grazing the livestock three or four times a week will not achieve the same effect.  Grazing every other day may seem a sensible way of using labour more efficiently and it certainly will not affect the pasture but the livestock will suffer. They must have a daily dose of protein supplement to allow them to digest the straw in great enough quantities to gain weight.

Production increase

Experimental results have shown that a medic pasture grazed in the way to produce a dense pasture that intercepts all the available sunlight will be twice as productive as an overgrazed pasture that barely cover the ground.

Weed control through grazing

    It is now time to think about weed control.

Under ideal circumstances the 8 cm height will control the weeds. The weeds will be grazed and this will prevent them from growing tall and shading the medic. This applies particularly to grass weeds. If they are not keep down from an early stage they will become dominant and shade the medic.

Keep down the grass and the medic is a strong competitor.

This a a good medic pasture on a small farm in Tunisia. There are weeds (and their flowers make them look prominent) but medic comprises more than 80% of the pasture. A short burst of over-grazing would control some of the weeds but not the thistles.

    Unpalatable weeds.

    These are more difficult to control.

It is quite possible to have a pasture that is generally 8 cm high but unpalatable weeds are growing through it to a greater height. The livestock, particularly sheep can be selective and graze the medic and grass leaving the unpalatable weeds.
   

The sheep can be forced to eat the unpalatable weeds by rotational grazing.

The pasture is divided into three or four areas, Instead of grazing the whole pasture each area is grazed intensively over a week or so. The pasture height is reduced below the 8 cm level and the production from the medic photosynthetic factory falls temporarily but the weeds are controlled.

The medic will bounce back and hopefully overcome the shading effect of the unpalatable weeds.
   

Some weeds are so unpalatable that sheep cannot be forced to eat them under any circumstances. This applies to many members of the thistle family. If these are not excessive in number shepherds should be encouraged to cut them off while they guard the sheep.

With the weedy fallow there is nothing else but if there are only a few weeds in the medic pasture they should be cut off to prevent seeding in the spring.

Other weed control methods

Grass weeds are a particularly problem.

They compete strongly with the medic. If the pasture is mainly grass not medic the production of nitrogen for the next cereal crop will be reduced. Grasses will also carry over cereal root diseases and the yield of the cereal crop will be reduced.

The section on weeds in cereals discusses these issues in detail.

As well as a short burst of heavy grazing in winter it is possible to reduce grass infestation by mowing or slashing. The idea is to cut off the grass seed heads at an early stage before they produce seed. The grass grows tall so it should be possible to cut them off without cutting off the medic which is growing to a height of about 8 cm if it has been managed correctly.

Spray grazing

This is a technique for selectively controlling broad-leaved weeds in a medic pasture.

The pasture is sprayed as early as possible in the season after the medic has reached the stage of having four true leaves. Hormone herbicides are applied to the pasture at a rate of about half what is recommended to kill the weeds.

The effect of the herbicide is to make the weeds more palatable and nutritious. About 7 to 10 days after spraying the pasture is heavily grazed. The sheep selectively graze the weeds and the medic, although slightly damaged, will take over the space occupied by the weeds. Once the sheep start grazing the medic they should be removed to another field to allow the medic to form a dense cover over the ground.

Hormone herbicides used for spray grazing control of broad-leaved weeds in medic pasture.

PRODUCT AND CONCENTRATION

RATE OF CONCENTRATE

mL/ha

COMMENTS

MCPA sodium (250 g/L)

500 -700

Apply when medic has at least 4 true leaves.

MCPA amine (500 g/L)

250-350

Apply when medic has at least 4 true leaves.

MCPA ester (800 g/L)

50 -100

Apply when medic has at least 4 true leaves.

2,4 - D amine (500g/L)

100 - 200

Apply when medic has at least 4 true leaves.

These herbicides are cheap and the treatment can be most effective.

Again it is often the case of shifting the balance and once a substantial reduction in weeds has been made the pasture can be managed by grazing without further applications of herbicide.


Bloat

    During my thirty-five years of experience of medic in the WANA region I have received a few reports of sheep dying from bloat when grazing green medic.

The occurrence of bloat is rare on annual medics certainly much less than with M. sativa, (lucerne or alfalfa). The circumstances when bloat occurs are clear.

The following factors cause bloat when combined together:-

    *  Winter grazing has been poorly managed. The pastures are too lush. The height is well over the optimum 8 cm.

    *  The sheep have been kept in the fold or shed for some days (usually due to bad weather) with inadequate amounts of hay and straw. They are taken onto the lush medic pasture with empty stomachs.

    * The shepherds have failed to take reasonable precautions when grazing these lush pastures. Instead of giving the sheep a short half hour on the pasture followed by a couple of hours off the pasture being fed straw they have allowed the sheep to fill up immediately.

    On one government farm in Tunisia the death rate from bloat dropped to zero when the shepherds were made to pay for the loss of each sheep from their wages. They made sure that the sheep were fed straw and did not graze the pasture too long. Once the sheep had become acclimatized over a few days there was no further danger.
 

Spring grazing - more than 8 cm.
 

    More grazing time - less straw.

    As the days become longer in spring the medic will grow more strongly. The livestock should be left in the field for longer periods to take advantage of the additional growth.

Less straw will be eaten in the yard at night.

Eventually no straw will be eaten. The whole diet will come from the medic pasture.

    Taller pasture.

    The pasture will grow taller than 8 cm. in spite of the fact that the livestock (in the case of sheep with lambs that are becoming weaned from their mother's milk) are now grazing for long periods every day.

    Flowering.

        In the spring the medic and other annual legumes will produce flowers that turn into pods.

        +   In our previous advice (see FAO Medic Audio Visual Filmstrip 1989) we recommended that livestock are removed when flowering begins for the first season of the medic pasture.

This was based on our experience that medic pastures were frequently over-grazed in spring. This may seem strange as spring is the period of maximum pasture growth. It is also a period of acute feed shortage with the cereal-fallow rotation. The weedy fallow is cultivated and the meagre pasture destroyed. The cereal crops have not been harvested. Livestock have few feed resources. Our experience was that the stocking rate on medic pasture often increased dramatically in the spring as livestock had no where else to graze.

The pastures were eaten down. The flowers and pods were eaten. The medic failed to regenerate in future years.

       +  If the medic has been planned to be in balance with the livestock (see Planning the stocking rate for medic) there should be no difficulties in grazing the medic in spring.

The previous advice can be ignored.

Of course no more sheep should be introduced onto the farm.  If the medic pasture is grazed there will be some further weed control of tall growing weeds.

The grazing of the medic in the spring has an important impact on profit.

One of the immediate effects of medic pasture is the faster growth of lambs in the spring. This will produce heavy lambs that can be sold at an earlier age for a greater return. Grazing the medic continuously through spring is important for good growth rates for lambs.

    Pods.

        What is true of flowers is even more important for pods. If the flowers survive the pods should. Only if more sheep are brought on to the medic pasture will the green pods be eaten.

This was a frequent problem in Jordan where not only was the weedy fallow cultivated in the spring but large numbers of hungry sheep came in from the rangeland and had little to eat until the cereal stubbles became available.

 

Green pods of a barrel medic pasture.

Drought
 

    If the spring rainfall is low and the medic does not grow it is important to reduce grazing to allow the flowers to turn into pods and drop on the ground.

This is vital in the first season as there are no pods in the ground from previous seasons.

Once the pods have dropped they can be measured (see  Grazing dry medic pods ) so they will be utilized and not wasted.

For an older pasture particularly one that is medic after medic, spring pod production is not important in a single year (for example Year 2 in the Zaghouan 4 rotation). These pastures can regenerate from previous reserves of pods in the soil. Pod production can be sacrificed on old medic during a drought in favour of areas that are being established.
 

Cold regions
 

    The northern parts of Iraq and Syria are extremely cold in winter as are the high altitude parts of North Africa. These are mainly the High Plateau of Algeria but also small areas in Morocco and Tunisia.

In these cold regions winter pasture growth in virtually zero because of the cold.

Farmers will need greater reserves of hay and straw for this period.

The spring season is longer and a later lambing is often a good strategy.
 

Other grazing terms and systems
 

Continuous grazing

Used on the parcour. The sheep flock is grazed on an area for the whole year.

Set Stocking

This is the method recommended above. The flock is grazed on one area for an extended period.

In the case of medic pasture from the period when the pasture is 8 cm high to the time when the cereal stubble is available for grazing. Many experiments have shown that set stocking causes fewer digestive upsets and souring for sheep. Growth rates are better and profits are higher.

Rotational grazing

    The sheep flock is moved regularly from area to area.

There are short bursts of heavy grazing followed by a period of recovery.

Some pastures such as M. sativa (lucerne or alfalfa) must be rotationally grazed but experiments have shown that set stocking is better for medic and other annual legumes.

Deferred grazing

     Used in the autumn to allow the pasture to build up a leaf area that intercepts all the sunlight.

Further information

How do you graze medic?  provides a photo guide to grazing management. The photos can be printed and used as a booklet for farmer. Alternatively they can be printed as a flip chart for extension workers.

Photo guide provides details of medic pastures at various stages.