by Justin West
In many parts of the tropics livestock such as cattle, pigs, and chickens are important sources of both food and income. However, the nutritional requirements of these animals often cannot be met by the marginal pastureland available. Typically, farmers make up the difference by purchasing bags of concentrated animal feed that contain grain, protein, and various necessary minerals and nutrients. The feed is expensive, though, which can lead farmers to overuse their pasture, causing the soil to erode and compact. As pastures become less productive, farmers then cut down trees to create new pasture, which leads in turn to further deforestation.
Integrated diversified farming systems, which aim to create a more efficient on-farm nutrient cycle and reduce off-farm inputs, provide a basket of potential solutions to this problem. One in particular, fodder banking, has the potential to enable greater control over the livestock production process while also increasing the ecological resilience of the system as a whole.
Fodder is any food that is fed to an animal, as opposed to forage, which is food that the animal goes out and finds on its own, such as grass in a pasture. Fodder banks are areas devoted to the production of high quality, nutrient-dense animal fodder. They are cultivated to increase resilience, improve food security, and insulate farmers from market volatility, although the mechanism by which they do this can vary from farm to farm and climate to climate. In tropical regions where there is a long and distinct dry season, fodder banks can produce feed in the off-season. In other regions farmers use them simply to reduce the amount of feed concentrate they have to purchase. Others have completely eliminated the use of feed concentrate by substituting a diverse mix of fodder crops. Often fodder crops are trees and shrubs that are cut back every one to three months. Some are nitrogen fixers, such as many of the trees in the legume family. Others are simply fast growing, easily regenerating, and often highly nutritious species.
In an effort to survey different types of fodder cropping systems in Costa Rica and Colombia, I visited seven farms, four in Colombia and three in Costa Rica. There were two clear take-home messages from this survey. First, the use of fodder banks is not widespread. The reasons for this remains unclear, but it seems likely that there are initial economic hurdles to establishing fodder banks as well as questions regarding labor costs, a lack of clear systemic information on how to manage them, and a cultural bias against planting trees in pastures.
Second, while many of the farms that have adopted fodder banks are using similar species — including mulberry, boton de oro, and nacadero — their methods for use, management, and cultivation vary quite a bit. Depending on the climate and cultural preferences farmers utilize different species to differing degrees of intensity. For example, mulberry provides a very high quality fodder and is fairly shade tolerant but requires good fertilization and a bit more time to regenerate (about 60 days versus 35-50 for boton). Nacadero requires more time than either of the other two but is more shade tolerant. Boton is more forgiving of low pH soils and is very fast to regenerate but provides a less nutritious fodder than mulberry or nacadero.
While many questions about fodder banks remain to be investigated, one of the most pressing is why some farms adopt them while other, neighboring farms do not. There is also a general lack of data quantifying the environmental benefits of fodder banks, which include protection from soil erosion, carbon sequestration, and drought resilience. Hopefully we will reach a point when we know enough about fodder banks to successfully integrate them into multi-strata agro-forests that mimic native forests. This would truly be a far cry from purchased bags of feed trucked in from tilled monoculture fields planted where native forests once stood.
Justin West is a graduate student in the Energy and Resources Group at UC Berkeley. He received a Tinker Grant from CLAS to travel to Colombia and Costa Rica in the summer of 2013.