The early rainfall received during February and March of this year was not conducive to the development of the borer stages awaiting emergence during the April-May period. Similarly, the sparse rainfall during June to mid July triggered the borer stages to develop faster but not fast enough to emerge as adults. The heavy and continuous rainfall during mid July to second half of August has caused natural death of many stem borer stages inside the borer affected plants.

Since the second flight or the winter emergence period is approaching, the borer stages are now getting into the pupal phase to gradually transform into adults. During this flight season all the borers inside the infested stem would emerge as adults to start a new cycle of six months and one year duration. Hence, it is very essential that the borer affected plants should be traced and removed before the end of September to prevent the spread of the adult beetles back in the field. During tracing, all the infested plants even if they carry some crop, should be removed. The stem borer prefers bright sunny weather conditions for its activities like flight, mate searching and egg laying and since the weather conditions during the approaching flight period can not be predicted precisely, it is best to take up proactive measures to manage the borer effectively. Once a coffee plant is infested, if such plants are allowed to remain on the farms, they only act as reservoirs for the supply of more and more beetles into the estate.

The infested plants should be removed every year before the flight period. If this is not done regularly, the cumulative effect would be very severe.

The interventions for manag­ing the stem borer are main­tenance of proper shade, mainly the lower canopy, regular borer tracing and destruction of infested plants and removal of loose scaly bark. Lime application on the main stein and thick primaries at the rate of 20Kg spray lime in 200 litres of water with 200 ml of Fevicol DDL may be taken up and completed within the first fortnight of October. Pheromone traps at the rate of twenty five per hectare can be installed by the first week of October to trap the emerging beetles. Adoption of a single component will not be able to bring about the desired result.