Livestock Farmers, Researchers and Scrub
1. Areas with uncertain value
2. The tradition of disciplinary approaches and their
renewal
3. New management methods to exploit the value of
scrubland
Conclusion
French grasslands have declined by roughly 3.5 million-hectares (25% of their
former area) since 1970 and forest-like scrub has gained 6.5 million-hectares
(1). Yet, from a strictly legal and
administrative point of view, forests have not significantly increased at
the expense of farmland. Former grasslands have evolved into intensified
grasslands on the one hand and rangelands that consist of coarser natural
grasslands, heathland and more or less dense undergrowth on the other hand.
In these areas, uniformity has lost all its rights to be and is gradually
being taken over by heterogeneity and variation. Agriculture has so widely
retreated from these rangelands that they are now subject to new designs
aiming at renovating or even rebuilding them, in a perspective taking Nature
for what it is, with all its diversities. That is the whole point of the
so-called agri-environmental measures aimed at "pastoral redeployment".
Small and large ruminants (sheep, goats, cows) have been set to work on these
abandoned areas to help carry out the scrub clearing operations. This idea
was easily accepted as it associates the agricultural world to the new
environmentalist perspective and as it resorts to biological rather than
mechanical or chemical brushcutters (Alphandéry et al., 1995
; Deverre et al., 1996 ; Hubert et al., 1996 ; Léger
et al., 1996). Yet, only 10% of the areas touched by scrub encroachment
due to agricultural abandonment have resorted to this method. More than 30
years ago, the modernisation of agriculture led to the development of many
technical principles and references, as much in the field of livestock farming
as in that of research. These principles and references are now being considered
from a totally different point of view by the authors of this article, who
are members of the technical committees for the implementation of
agri-environmental measures in the Baronnies (Drôme - pastoral redeployment
for the maintenance of an open landscape) and in the Lubéron (Vaucluse,
- pastoral redeployment for the maintenance of rare biotopes), both in the
hills of south-eastern France.
[R] 1. Areas with uncertain value
Modern livestock farming has progressively abandoned grazing practices and
has turned to trough feeding, thus animals no longer move around. These animals
are selected according to animal performance criteria and require highly
nutritional feeds to allow them to fully express their genetic potential.
Agricultural and agronomic education still considers that optimisation is
obtained by correctly calculating food rations. A more general culture in
the field of livestock farming is somewhat lacking, due to the development
of increasingly standardised technical references (Landais et Bonnemaire,
1996). Yet, when a livestock farmer is encouraged to put his animals out
to graze on scrubland, he soon notices that these technical references are
practically inexistent: it is almost impossible to accurately calculate a
food ration for such grazing lands. Herds move around and are subject to
changes in the temperature, which makes it impossible to accurately estimate
their energy requirements. More over, they feed on a diversity of plants
that are not generally referenced in traditional food charts (Jarrige, 1988),
thus it is impossible to estimate the quantity or quality of the ingested
food.
Therefore, these grazing lands are considered to offer high-risk feed resources,
and when livestock farmers nevertheless wish to put their animals out to
graze, livestock technicians (now involved in the technical committees for
agri-environmental measures) encourage them to play it safe by feeding the
animals large supplements of hay and concentrates. This is in fact rather
untimely as supplements turn animals away from grazing coarse resources.
While waiting to be comfortably and predictably trough-fed, the animals focus
on the plants they prefer (which often only constitute 10 to 20% of the land
to be grazed) or remain near the gate area, with the result that grazing
does not rid the livestock farmers of undesirable plants. The areas left
to themselves rapidly become overgrown and, little by little, lose their
value in the eyes of the livestock farmer as "my animals no longer go there".
[R] 2. The tradition of disciplinary approaches and their renewal
Plant ecologists and agrostologists have long tried to set the "objective foundations" for assessing the value of grazing land, by elaborating "Pastoral Value" charts (PV) for a wide range of grazing environments (Daget et Godron, 1995). The Pastoral Value is based on the botanical composition of the plant cover, its total area and on a theoretical index representing the nutritional value of each plant for a ruminant. In a fenced paddock, with a multitude of plants, the average PV is based on the average PV of each homogeneous plant unit, related to its area. This method, which attributes a specific value to each plant unit, is used to reference the "carrying capacity" of an environment, at a regional scale or even at the scale of a continent. This "all-purpose" approach is similar to that of nutritional value charts and the debate on the management of scrubland through grazing cannot possibly be based on these references. These references are under the direct influence of animal nutrition models based on the study of high energy diets, favouring a high level of fibre at the expense of a good quality nutritional value, and are underpinned by a clear-cut statement: scrub encroachment deteriorates grazing lands. Good grazing land should only consist of grass. This leads to a univocal recommendation: "clearing your land increases its quality!", a recommendation which certainly does not lead livestock farmers to set their animals out to graze on scrubland.
Figure 1. Self-service supplement supply in a large paddock
(roughly 10 hectares)
The flock focalises on this food supply and frequently goes to and from this
point, consuming various resources on the way. Thus, from a distance, livestock
farmers can influence the grazing habits of their animals, by encouraging
them to graze (see example above) on generally "non-preferred" areas, thus
preventing scrub invasion (Meuret, 1997).
However, thanks to interdisciplinary work, some studies have recently called into question certain well-established ideas. The morphogenetic study of grasslands has led researchers to conclude that botanical surveys do not correctly indicate the value of the latter (Fleury, 1994). They add that, depending on the plant morphology, animals perceive less difference between the leaves of different plants than between the leaves of the same species (bushy plants, smaller ones, creepers) - as regards nutritional value and attraction ("palatability"). They also show that the "use value" of heterogeneous plant covers can be assessed by locating "homogeneous physiognomic units" and the corresponding specific growth dynamics. Nutritionists, on their side, are presently reconsidering some of the main principles of animal food rations (Jarrige et al., 1995 ; Provenza, 1996). By associating a more ethological point of view to the analysis of digestive dynamics and their effect on animal behaviour, nutritionists show that time plays a fundamental role in interpreting the animals' motivation to eat. Choices made by animals at a given moment in time are dictated by the long term dimension of their early training and to the short term dimension of their memory of the post-ingestive consequences of prior choices. Thanks to this progress, the notion of "immediate palatability" (Sauvant et al., 1996) has been acknowledged and a plant's value is no longer considered independently but in association with all the different plants the animal is faced with.
[R] 3. New management methods to exploit the value of scrubland
Our research now allows us to say that scrub is a valuable food resource,
to be mastered in the framework of the new agri-environmental measures. In
order to evaluate the latter in terms of quality, for both the landscape
and animals, it is necessary to adhere to new herd training and feeding
principles (Leclerc et Lécrivain, 1979; Meuret, 1993; Meuret et
al., 1995). Paradoxically, the current concern of farmers is to develop
the value of grazing lands; this reveals that the "time" variable although
rarely taken into consideration in animal feeding, has become a major
issue.
When trained at an early age, animals acquire the ability to explore scrub,
generally through observing their more experienced mates. Ewe lambs put out
to graze on scrublands in their first season, with experienced gregarious
adults, are quickly integrated into the flock and consume over 15% more scrub
than ewe lambs that formerly grazed on grasslands (Lécrivain et al.,
1996). Over the years, a flock of ewes regularly graze in this kind of
environment can "acquire a taste" for scrubs and their food rations often
contain over 60% of these plants; they thus adopt the behaviour of goats
(Lécrivain et al., 1989). Livestock farmers have means to educate
their herds or flocks: they can choose when they will confront young animals
to a given vegetation according to their age and the season; they can mix
both experienced and naïve animals in their herds; they can put their
animals out to graze in paddocks that are designed in such a way as to encourage
animals to get used to generally less appreciated plants.
As regards grazing, in heterogeneous areas where animals are supposedly left
to themselves, farmers have the means to polarise the movements and control
the activities of their herds all through the day, so as to indirectly control
the way animals will use the paddock. They can orient the choices and the
impact of their herds and thus can satisfy the agri-environmental specifications
requiring an impact in circumscribed areas. By determining the spatial
configuration of the paddock, the location of the gate and that of the water
points or self-service supplementary feed supplies, the farmer can add an
attractive feature to each area of the paddock. The importance of these features
varies as the animals prefer different areas of the paddock, according to
the time of the day (Meuret, 1997). If herds are let out daily, the paddock
gate becomes the "focus point". This will orient the herd's movements and
influence the areas that will be grazed several hours before the animals
are herded into the paddock. We thus observe that, when goats are grazed
in coppice vegetation, they can be made to browse the species they theoretically
appreciate least (i.e. downy oak foliage as opposed to evergreen oak) from
the first day onwards if the gateway is placed near an area where downy oak
is plentiful (Leclerc et Lécrivain, 1994). As they expect to return
to the goat shed, the animals remain in this area for over two hours every
day; they are subject to a double motivation: remaining near the gate, while
having a meal.
When putting animals out to feed on grazing land, the scrubland heterogeneity
should not be considered as a handicap but as appetite stimulating. In such
environments, the consumption of meals consists in a succession of long phases
where animals consume the most abundant and often coarser plants, interrupted
by short phases where they consume rarer species of a very different nature
(Meuret, 1996 ; 1997). A typical illustration is that of goats put out to
graze in overgrown coppice: the animals will eat oak leaves as long as they
can diversify their feed and are regularly provided with attractive leguminous
shrubs or creepers. It is also the case of ewes paddocked on rangelands:
their motivation to feed on mature grass areas at the ear stage is regularly
reboosted by a feeding spell on broom. Therefore, broom, which is generally
considered as an invasive plant, is useful to diversify meals from time to
time and thus to reboost the appetite of sheep for grasslands. Composite
mixtures of plants, including scrub, can thus generate "nutritional synergies"
that positively encourage animals to graze.
Figure 2. The "menu" model
A shepherd can use the heterogeneity of the grazing land to organise
his circuit in such as way as to stimulate the appetite of his flock. By
frequently observing the reactions of his flock at midday (the circuit thus
corresponds to a meal), the shepherd can judiciously move to areas contrasted
in "immediate palatability" and with abundant resources. This succession
of "courses" has a positive influence on feeding synergies and boosts the
animals' appetite for the "target area", which consists in resources that
are not generally eaten (Meuret, 1993).
M: moderation SA: appetite stimulating MD: main course Ba, Bb: reboosting
SD: second course D: dessert
The new agri-environmental policy therefore encourages new technical modalities
in livestock farming, especially as concerns the assessment and valorisation
of grazing resources. The aim is to turn away from the standardising principles
that were, up until now, legitimated by intensification at the expense of
new more localised savoir-faire. Nevertheless, we are still wide off the
mark, although livestock farmers test many new procedures, often used in
other countries (New Zealand type fencing (2)
or training dogs as they do in Scotland
(3)) and although researchers from different disciplines
are starting to produce means to reason the techniques needed for pastoral
redeployment.
The agri-environmental policy has led researchers and farmers to question
former practices and to innovate, yet they are still faced with many
uncertainties, especially in the technical field. Its bending of reality
to fit predefined development or land planning schemes cannot be based on
a certainty and savoir-faire stemming from technoscience. Therefore, since
the agricultural policy of the "Trente Glorieuses (the thirty glorious years
of economic development in France) right up to the major turning point of
the Common Agricultural Policy in 1992, the situation has immensely evolved.
To start with, there is no major consensus behind the aim of opening up scrub
invaded landscapes, as there was before when agricultural production had
to be increased in order to feed the world's inhabitants. It is now the fruit
of laborious negotiations between diverse actors who, around the table of
local committees, finally agree on eligible areas, priority actions, etc.
Moreover, the means to be implemented, as set out in the list of specifications,
are not clearly apparent in this objective owing to the diversity of the
social and natural environments concerned. This diversity must be conserved
and not ignored as it was in the former modernisation programmes. Also, when
planning to open up a stretch of land, and particularly a scrub covered stretch
of land, there is a dynamic dimension involved that is difficult to gauge
at the outset. Demonstrating that scrub can be a valuable resource does not
imply that one can predict that this particular stretch of land will remain
open in a foreseeable future. Indeed, animals do not like all types of scrub
and the inedible species may in turn take over the landscape once again,
as is the case with Scots pines in the Baronnies or with boxwood in the Luberon
hills.
With agri-environmental measures, livestock farmers and researchers actually
play the role of experimenters of scrub management, and not of developers
with easily recognisable performances. There is no guarantee that these measures
will define coherent means and objectives. Therefore, to encourage means
and results, the relationship between decision-makers and farmers cannot
be based on precisely defined functionalities, that are nevertheless the
authority at the time of controls and assessments.
Paper based on a contribution to the seminar on the Rural
Economy of French Society - The agri-environmental measures, the first
conclusions of the European experiments: a multidisciplinary perspective,
3rd and 4th November 1997, Paris.
This article is taken from the "Courrier de l'environnement
de l'INRA, n°35", by J.-P. Chabert, E. Lécrivain and M.
Meuret.
Translated from French by Nicole Scott.
[R]
Notes
(1) Source: Les
données de l'environnement, n°25, October 1996, periodical published
by the French Environment Institute (Institut français de l'environnement
- IFEN); National Forest Inventory (Inventaire forestier national),
1996.[VU]
(2) New Zealand has made a breakthrough in the field of fixed
and mobile electric enclosures. They offer integrated kits with either high
resistance iron wires, flexible conductor and current-carrying wires in plastic
housing, wooden or plastic stakes that can be equipped with a large number
of insulators, and even transmitters that can accurately identify any failure
in the system and can be operated by remote-control when it is necessary
to intervene. They also offer a whole range of machines, motorised or not,
to help with all installation or removal. Mobile enclosures are especially
interesting for livestock farmers with no land and who wish to impress landowners
by showing them the impact of grazing on the environment, before negotiating
a further contract. Various types of enclosures can be easily overcome by
walkers, hunters and their game, and were specifically invented for a
multifunctional use of space.[VU]
(3) Border Collies are used by livestock farmers who need
to round up their animals and to lead them from one paddock to another. This
Scottish breed is used in modern open-air livestock farming, whereas French
breeds (Beauceron, Briard and Labris, amongst others) are used by transhumant
shepherds, who have to keep their animals inside invisible yet precise
boarders.[VU]
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