East Bank, Cley – Control of invasive vegetation

Management of East Bank (and other flood defence structures) invasive vegetation (Alexanders) by the Environment Agency is an emotive issue and one which has led to the periodic raising of concern etc. Both David Griffiths and Chris Gooddie (primarily) have written to the EA to challenge the cutting back of vegetation. Chris’s engagement has led to us (David, Chris and George Baldock) meeting with representatives from the EA on 30 March.

Over time the EA has become responsive to a possible locally resourced plan to control the Alexanders by manually cutting them back to a height of about 15cm three times a year during the breeding season after the initial early season mechanical cut. Our meeting was to discuss the practicalities of volunteers cutting back the Alexanders every six weeks through the late Spring/Summer season. EA would provide a Risk Assessment and briefing should we proceed.

The practicalities of undertaking this task are not insignificant. The area in question on East Bank is approximately 13,600 square metres. We undertook a brief trial with secateurs to cut down some Alexanders – they are robust and the area in question would require some 130,000-200,000 cuts based on 10 to 15 cuts per square metre. We believe that this is a daunting task even on the flat, let alone on a 45-degree slope with water in the near vicinity.

We have therefore concluded that manual cutting every six weeks would be a physically challenging activity, with some significant risk to volunteers. EA use remotely operated cutting machinery as part of a major operator risk reduction strategy.

Our plan now is to mark out the locations of any ground nesting birds on both West and East Bank before the EA undertake the next series of cuts in April. You can help by letting us (DG) know if you see/suspect any nesting activity on the banks. Over the last few years this has been solely by Meadow Pipits and we intend to mark out the nesting areas to avoid mechanical cutting in these areas. EA have agreed a marking strategy.

We understand that you may remain frustrated by the management of the flood defences using mechanical means, but we believe that physical management using secateurs/shears is impractical on this scale. EA hope that by regularly cutting back the invasive Alexanders and then re-seeding using fast growing rye grasses and wildflower mix that the natural botany of the banks will eventually recover.  EA are monitoring the results of their current process to see if it results in effective control of Alexanders, and are currently in year 2 of a 5-year study. If the current cutting regime proves ineffective it may be abandoned in the future.