COMHAIRLE CONTAE ÁTHA CLIATH THEAS
SOUTH DUBLIN COUNTY COUNCIL

MEETING OF RATHFARNHAM/TEMPLEOGUE-TERENURE AREA COMMITTEE

Tuesday, April 10, 2018

HEADED ITEM NO. 12

Japanese Knotweed & Other Invasive Species

This matter was last reported on to this area committee at the December 2017 meeting. The current position is as follows.

The surveying and mapping exercise was carried out from July to November 2017, a summary of the findings of the 2017 survey were included in the report which was presented to the December meeting.  The surveys were largely completed however it was reported in December '17 that some areas along the Dodder when visited in 2017 were found not to be accessible to the surveyors.  These areas, mostly upstream of Old Bawn bridge, will be surveyed and mapped in the Spring of 2018 and these surveys have just recently recommenced.   

The surveying and mapping of areas along the Owendoher River and Whitechurch Stream was successfully completed in 2017, and all of these areas were also successfully treated.  Signage was erected at 10 of the sites where it was considered necessary to inform the public of the matter.  Surveying along the Poddle river was also successfully completed in 2017 and all relevant sites have been mapped and treated and this includes those sites which were identified in Tymon Park.

The number of sites in the Rathfarnham/Templeogue-Terenure area found through the surveys to be affected by Japanese Knotweed currently stands at 43.  It is expected that this number will rise as the areas mentioned above which have not yet been surveyed are visited.  It is also expected that further sites will be reported by members of the public and found by Council staff through the course of the year and therefore this number is expected to rise further for this reason also.  In this regard 2 additional sites have been reported to the Council by members of the public over the winter months and these are now due to be included in the surveying, mapping and treatment programmes. 

Two staff members continue to be assigned to this project on a full time basis and this will remain the case in 2018, with additional staff to be assigned to the treatment programme if required.  Based on the information gathered over the past 9 months it is expected that this will be sufficient to complete the survey and treat all areas twice during 2018.  The programme to survey, map and treat Japanese Knotweed will continue until such time as we are satisfied that the matter is under control.  An assessment will be carried out at the end of the current year to compare 2017 findings with those from 2018.  While it is expected that some additional sites will be found in 2018 it is also expected that the effects of the treatment programme will be evident and this will hopefully show a reduction in the size/plan area of those sites which are affected.