Bidirectional movement of aphid parasitoids (Braconidae: Aphidiinae) between crops and non-crop plants in agroecosystems of central Argentina
Alfalfa is the most important forage crop in Argentina, where about 4.7 million hectares are grown. In the Pampa Region, more than 90% of the area devoted to alfalfa is utilized under direct grazing for both beef and dairy production. In this paper we discuss the main concepts necessary to implement adequate and practical rotational grazing systems. Particular attention is given to issues such as grazing frequency, grazing period, pasture use efficiency, and alfalfa quality variation by canopy strata and time of year. Specific management requirements for beef and dairy operations are also discussed. Direct grazing can play an important role in reducing operative costs and decreasing quality loss due to forage conservation (hay or silage). Argentine experience indicates that is possible to reach high animal response under direct grazing, provided appropriate management practices.