In 1998 Norton offered an explanation for why researchers and commercial producers have opposing views on rotational grazing. Most researchers agreed to a lack of evidence of an improvement to forage yield or animal production due to rotational grazing, while producers were generally happy with higher production and income. He attributed this difference to a question of scale: research studies in small paddocks carry the implicit and reasonable assumption that both forage availability and its utilization are spatially homogeneous, whereas those parameters are highly variable across a continuously grazed rangeland landscape. Rotational grazing can ameliorate the patch grazing patterns encountered on extensive rangelands. An unheralded outcome from many grazing trials is that the stocking rate on experimental pastures could be maintained at much higher rates than on commercial properties near the research station, without adverse ecological impacts for either treatment. This appears to be a small-paddock phenomenon. Since 1998, many studies have looked at rotational grazing at a landscape/property scale with mixed results : some positive, some neutral, some negative. However, the adoption of rotational grazing on 130,000 ha of communal rangeland in Central Asia is a testament to its potential benefits to land, livestock and households. Adding to the confusion, recent meta-analyses of grazing studies have generated contrasting conclusions. The key issue appears to be the degree to which the design of a rotation is reflected in the plant/herbivore interface. A disconnect between the intended treatment and its expression in grazing behaviour is evident when defoliation frequency has been measured in grazing trials. We can hypothesize, therefore, that failure of the rotation treatment to be implemented as intended could explain a lack of differentiation between continuous versus rotation treatments. This paper surveys rotational grazing studies to examine this hypothesis.
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