the residual effect of herbicides on soils; however, organic farmers
were more concerned than conventional farmers regarding the effects
of chemical fertilisers.
Farmers’ knowledge related to the effectiveness of shade trees
in regulating humidity to manage fungal diseases was also found
(Table 5). Farmers frequently mentioned two fungal diseases: coffee
rust (caused by Hemileia vastatrix) and American leaf spot
(caused by Mycena citricolor). Almost all farmers expressed that
in order to avoid American leaf spot, shade percentage should be
kept high throughout the year (this was always compared with
other coffee areas in Costa Rica). Due to its ease of pruning and
resilience to frequent severe pruning, farmers consider E. poeppigiana
as the best tree for the area. In general, trees should be pruned
twice a year to favour drying within the plantations during certain
months of the year.
3.5. Generalisation of farmers’ knowledge regarding ecosystem
services
Farmers’ knowledge compiled within the purposive sample was
different from the knowledge expressed within a bigger sample of
farmers during the stage of generalisation (Table 6). Not all farmers
knew or understood the same issues and each farmer knew the different
issues to various degrees.
Even if the causes of climate change are not well understood, its
consequences were strongly perceived and affected coffee farming
practices during the year. For example, farmers mentioned that
fluctuations in the distribution of the rainy season have increased
the duration of coffee flowering. They also mentioned an increase
in the severity of coffee fungal diseases due to climate change in
the past few years. In some low areas, tree-pruning regimes have
been modified in order to provide a fresher microclimate for coffee
plants. Farmers used to prune severely twice a year, pollarding all
branches of E. poeppigiana. Now farmers are pruning with the same
frequency but keeping two or three branches without pollarding.
The discourse on ecosystem services was found to differ with
the farmers’ specific necessities and conditions. For instance, tree
species diversity within the farm was mentioned more frequently
among organic farmers, as well as the perceived resources that animals
obtained from different trees. Organic farmers constantly
mentioned that conserving forests surrounding coffee plots is very
important for faunal conservation. Organic farmers were also the
only farmers to mention secondary succession by tree species pioneers
and other specific issues.