White Butterbur Control Trials River Fiddich Spey Catchment

White Butterbur (Petasites Albus) Introduced in the 1600’s, Invasive in NE Scotland from late 1800’s Rhizomatous plant with dense foliage and early White flowers (Feb/Mar) Little research on impacts and control to date Favours open riparian woodland

Potential Impacts Huge loss of biodiversity River bank destabilisation, increased sedimentation of watercourses Significant threat to long term health of riparian woodland

Addressing Control - Field study Extent of infestation on Fiddich so large reluctant to use Herbicide alone Two trial sites on the Fiddich established to test alternative treatment methods in the hope of creating effective management advise Each site divided in to 24 4mx4m plots with buffer zones in between Methods tested: Herbicide application, Digging and Strimming

Initial Observations Method Time taken (av) Comments Glyphosate Max concentration < 5 mins >98% effective Glyphosate 50% Digging – Remove Rhizomes 130 mins 70 - 90% effective – Large variance across plots Digging – Rhizomes left insitu 63 mins 40-60% effective - Suspect strong regrowth later Strimming – Removing Cuttings No measurable effect on density Strimming – Cuttings Left Work was carried out in August favouring herbicide application against strimming Plots will be strimmed in April/May in 2019 to ascertain whether earlier/repeat treatment effective Digging highly dependant on volunteer motivation and energy – consider bribing with tea & chocolate 50% of plots to be seeded with native wild flower mix

Initial Observations… in pictures

2019 and beyond…

www.invasivespecies.scot sisi@nature.scot James Symonds J.Symonds@SpeyFisheryBoard.com Image credits; NNSS,, Ryzhkov Sergey CC BY-SA 4.0,