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Beef Breeder MANUAL
• What labour and inancial resources are available for forage development and management?
• How many livestock require feeding? • What type and class of livestock require feeding?
• What level of production is expected? • What other sources of feed are available?
• What is the feeding value of all these feeds? • How will livestock be fed during winter?
• Is the forage permanent or a short-term forage? i.e. will the forage be part of a crop rotation?
• How will the forage be utilised - grazed or conserved?
• What forage species are adapted in the area? • Which forage species are best suited to the farming
system? These questions help to deine the role of the forage in
a particular farming system.
9.2.1. Plant Adaptation
Plants have evolved to grow and reproduce under a particular range of environmental conditions, and in
general, the further they are removed from their native environment, the less thrifty they become. For example,
some plants grow in deserts, others in swamps; some grow in fertile soils, others in infertile soils; some grow
in cold climates, others in hot climates. There is also considerable variation between and within plant species
in their adaptation to various soil conditions.
Plants that are eaten by animals also have developed speciic adaptation to frequency and intensity of
defoliation. Plants that are rarely grazed or browsed in their native environment tend to be taller and more
upright than those that are frequently heavily grazed, the latter often being more prostrate, with stems that root
down on the soil surface stolons or even creep below the soil surface rhizomes.
It is important, therefore, to know the characteristics of plants, their tolerances and susceptibilities to ensure that
they are compatible with the system into which they will be introduced. Use of plants that are poorly adapted
to the local environment will result in an unsustainable system.
9.2.2. Forage Species
Most sown forages come from the two large groups of lowering plants; the grasses and the legumes. About
10,000 grass species and 18,000 legume species have been identiied around the world. Apart from this
large number of species, there are many genotypes within each species, giving enormous variation overall.
However, not all grasses and legumes are eaten by grazing animals and not all legumes ix nitrogen.
Over the years, researchers around the world have identiied species in the various agro-ecological zones
with characteristics that might be valuable in sown pasture systems good palatability and feeding value,
wide adaptation, persistence under grazing etc.. Large collections of genotypes within these species have
been made by trained plant collectors, and saved in seed banks called Genetic Resource Centres in many
of the key countries. New varieties are produced from research programs selecting the best types from the wild
collections, or breeding programs designed to combine useful traits identiied in the various wild species.
Forages are classiied in various ways; on the basis of plant relationships, plant types, or adaptation Table 9.2.
Hence, a producer might need a late lowering, perennial grass, adapted to a poorly drained, infertile clay soil to
satisfy the forage needs in their particular system.
9.2.3. Legumes
