Agriculture and Environment: Cashews
Environmental Impacts of Production
Cashew nut production has long been undertaken on a smaller scale than many agricultural commodities.
Most of the money from cashews is made not from producing them but from shelling them before selling them into the market. For this reason, investments have taken place at the shelling level rather than at the production level.
Damages much less than others
This means that there have been few plantation-scale areas of production and few purchased inputs designed to increase production. Both of these factors mean that the environmental damage from cashew production has been less than for most other commodities.
Plantations in Brazil, Africa
Unfortunately, however, some plantations have been established. Given the harsh conditions that the tree is able to withstand, many of the affected areas have vegetation that would never otherwise be cleared for agriculture. For example, large expanses of cooperative plants of thousands of hectares of cashews are now planted on some interior scrubland areas (caatinga) in northeast Brazil.
Similarly, small farmers have pushed cashew planting into many coastal areas of East Africa as well as the interior areas of southern Africa (e.g., in the Miombo). While individually the plantings are small, collectively they have a large cumulative impact on natural habitat.
Some producers do use pesticides and fertilisers on their crops. By 2000, however, this was the exception rather than the rule. So long as the markets do not increase dramatically for cashew nuts, these impacts are likely to be within acceptable limits because producers will not be able to afford the inputs.Habitat Conversion
With 97% of the total cashew crop produced by small farms or collected from the wild in Brazil, there is still very little large-scale habitat conversion associated with the production of cashews. Plantation establishment could pose environmental impacts, especially in drier, often more fragile and more marginal areas.
Agrochemical Use
There is very little weed control involved in cashew production, other than allowing livestock to gaze beneath mature trees. As a result, herbicides are generally not used. Similarly, there are few fertilisers used in cashew production (other than urea rock phosphate and muriate of potash during initial planting), and these are applied very sparingly due to their cost. In fact, most farms do not receive any fertilisation for years.
Few if any pesticides are used in cashew production in most areas. However, in some parts of Africa two species of Helopeltis can damage cashew trees by sucking juices from the leaves, young shoots, and inflorescences.
These pests have been controlled by dieldrin sprays or sprays or dusting with benzene hexachloride (BHC), or DDT plus BHC (Agriculture News from Africa 2002). If the area for cultivating cashews is large, aerial sprays can be employed. This creates a potential for pesticide toxicity as the pesticide mixture is sprayed over a large area.
One reason for the minimal use of agrochemicals is that producers do not perceive cashews as an important profit-making crop. Rather, it is an insurance for obtaining income with high costs during lean times. On many cashew farms the cashew is in fact the vegetation that provides the most food for wildlife; in many areas there are few sources of food for wildlife with as high nutritional content.
