This is a handout by Brian Freking from the 2011 Healthy Soils, Healthy Livestock conference. It is a fact sheet answering common questions about electric fencing.
Rotational grazing requires using fences – permanent, temporary, or a combination – to keep cattle where the grazier wants them to harvest forage.
In continuous grazing, a single pasture is grazed 100% of the time with no rest period.
A single fence dividing that pasture into two increases the rest period from zero to 50%, and reduces the grazing period for both pastures to 50%.
Each additional paddock in the grazing system further increases the rest period and reduces the grazing period. This figure illustrates that pattern.
Source: Lemus, R. 2008. Developing a Grazing System. Forage News. Mississippi State University Extension Service. http://msucares.com/crops/forages/newsletters/08/6.pdf
Electric fencing is a lower-cost option for subdividing larger, permanently fenced pastures. It also allows more flexibility – paddock sizes can be adjusted to the amount of available forage, the number of cattle, and the desired length of the grazing period.