Cultural Controls Las Brisas farm workers make regular harvest pickings of mature berries as soon as they ripen, usually every 21 days but increased to every 15 days in plots with higher CBB levels. Although there are two main harvest peaks per year in this part of the country, Don Guillermo earns some income from the small volumes of coffee collected in these regular ‘sanitary’ picking rounds throughout the year, so this cultural control to remove potential CBB attack and breeding sites (ripening and mature berries) pays for itself in labour terms. His system of intensified, post-harvest sanitary controls takes place every 3-4 weeks after the major and minor peak harvest periods. These controls consist of rigorous collections from identified borer ‘hotspots’ (trees with more than 5 bored berries from sampling) plus their 6-8 neighbouring trees, removing all berries from the ground and any overripe or dry berries on the branches. This helps to remove from the groves very large numbers of high risk CBB breeding sites – several generations of borer can reproduce inside each fallen or dried berry left on the tree.
“Biological products need to get established and they work more slowly. It’s a question of understanding, being sure about what a biological product will do… You’ve got to be patient because you won’t see the results the next day, nor one or two weeks later, but you’ll keep applying and gradually see the fungus getting established and then start seeing the effects”. Don Guillermo Londoño
Physical controls Berries collected from hotspots and from second harvest passes are collected in greased lidded containers (to capture any adult borers emerging) and put into hermetically sealed barrels for 24 hours. As berry fermentation starts, carbon dioxide gases released kill any borers inside or emerging. Many of these berries can then be processed and sold as second grade beans. Don Guillermo employs simple barrier controls (mesh filters, greased plastic covers) at pulping and processing stations to collect any live borers emerging from berry pulp or collection containers. He has smoothlined funnels for delivering the washed berries into the pulping machine, rather than the traditional wooden ones, so that there are no cracks where escaped borers can survive. While none of these physical methods are major controls, they all
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‘Worm juice’ from vermiculture composting units produced by La Palmera coffee estate, Colombia, for sale as an organic fertiliser. Stephanie Williamson
help to reduce the risk of borers re-infesting clean plots. Biological controls CBB adults and larvae can be infected and killed by the naturally occurring insect pathogenic fungus Beauveria bassiana. This fungus is often present