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Acer Negundo Insights from Experimental and Physiological Studies

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Acer Negundo Insights from Experimental and Physiological Studies Control of Acer negundo insights from experimental and physiological studies Merceron N., Lamarque L.J., Brogniez S., Ducournau Y., Buyle S., Degrave L., Roudie J., Felis O., Moreau A., Vernin P., Guengant Y., Delzon S., Porté A.J. [email protected] 4th International Symposium on Weeds and Invasive Plants, Montpellier, 19-23 May 2014 1 Target species : Boxelder maple (Acer negundo) Light green foliage Fast-growing Dioecious species Seed dispersal by Resprouts from Source : urban plantations wind and water the stump 2 Distribution areas introduced in Europe in 1689 (GB) around 1749 in France Native range Invasive range 3 Lamarque LJ, PhD (2013) Invaded habitats Riparian forests and wetlands Local distribution Fraxinus sp, Acer negundo Salix sp, Quercus sp Populus sp, = Alnus sp = LATE- INTERMEDIATE SUCCESSIONAL POSITION + = PIONEER SPECIES RIVERBANKS SPECIES 4 Negundo negatively impacts native tree species Density 5 Lamarque et al. 2012 Ecography Negundo dominates native tree species 1 Frequency Adults 0.8 0.6 Acer negundo Native tree species 0.4 0.2 0 Acer Fraxinus Alnus Salix alba Populus Sambucus Ulmus Corylus Crataegus Prunus Quercus negundo excelsior glutinosa nigra nigra minor avellana monogyna spinosa robur 1 1 Saplings Seedlings 0.8 0.8 0.6 0.6 0.4 0.4 0.2 0.2 0 Acer Fraxinus Prunus Ulmus Populus Corylus Sambucus Salix alba Quercus Crataegus Alnus 0 Acer Quercus Fraxinus Ulmus Corylus Salix alba Prunus Populus SambucusCrataegus Alnus negundo excelsior spinosa minor nigra avellana nigra robur monogyna glutinosa negundo robur excelsior minor avellana spinosa nigra nigra monogyna glutinosa 6 Methods in Lamarque et al. 2012 Ecography Local context : ecological and economic impacts • River bank collapse • Lower nesting • Production and conservation concerns : . Replacement of Populus (paper pulp), Alnus (energy) . Protected areas 7 Questions ? Can we control Acer negundo establishment? In which way? 8 Main methods to control invasive trees Mortality rate (%) of resprouting invasive species 100 80 60 All species 40 Acer sp 20 0 Biological Chemical Mechanical 9 Review 50 articles Main methods to control invasive trees Mortality rate (%) of resprouting invasive species 100 80 60Prohibited in natural areas (wetlands, forests …) All species 40 Acer sp 20 0 Biological Chemical Mechanical 10 Review 50 articles Experimental sites Experiment 1st year of 2nd year of 11 setting up measurements measurements Experimental sites 1%1% 0% 7% 0% 1% Salles 3% 0% Bruges 11% Acer negundo Acer negundo Populus sp Fraxinus excelsior Alnus glutinosa Ulmus minor Ulmus minor 16% Quercus robur Carpinus betulus Alnus glutinosa 69% 91% Quercus robur Platanus sp. 1% 1% 4% 0% Marestaing Acer negundo 22% Ulmus minor Fraxinus excelsior Alnus glutinosa Populus alba 72% Salix alba 12 Experimental treatments Cutting Large girdling Juglone 1.30 m 1.30 m 0.20 m 0.20 m C H G J Cutting + Cutting High cutting Girdling Juglone 13 Experimental treatments High cutting Large girdling Juglone 1.30 m 1.30 m 0.20 m 0.20 m C H G J Cutting + Cutting High cutting Girdling Juglone 14 Experimental treatments Girdling Large girdling Juglone 1.30 m 1.30 m 0.20 m 0.20 m C H G J Cutting + Cutting High cutting Girdling Juglone 15 Experimental treatments Juglone Juglone = allelopathic substance with herbicide properties Large girdling Juglone 1.30 m 1.30 m 0.20 m 0.20 m C H G J Cutting + Cutting High cutting Girdling Juglone 16 Experimental treatments Measurments : • Mortality : mortality rate (%) Juglone = allelopathic substance • Vitality : diameter of the five with largest resprouts herbicide properties Large girdling Juglone 1.30 m 1.30 m 0.20 m 0.20 m C H G J Cutting + Cutting High cutting Girdling Juglone 17 Mortality rate (%) 100 80 b 60 40 a Percentage 20 A a A a A A 0 Cutting Girdling High cutting Juglone Treatments N+1 N+2 Mortality rate by girdling best method 18 Diameter of resprouts 12 A A 10 a 8 B (cm) b 6 c C d 4 Diameter 2 0 Cutting Girdling High cutting Juglone Treatments N+1 N+2 Girdling limits diameter of resprouts 19 Control method of A. negundo in natural areas Adults: girdling • Control rather than eradication • 2-3 year long • Stand level method Seedlings: removal • No germination • No seed rain • Long distance dispersal? Scars reconstructing the phloem tissues 20 High level of plasticity to nutrients and Light • Growth (Relative Growth Rate) 12 Invasive Native 10 ) 1 - . d 1 - 8 6 . mm. mm mm. 3 - (10 4 h RGR 2 0 Full lightC Light Sshade DeepSS Shade FullC light Light Sshade DeepSS Shade N+ N- Nutrient Supply No Nutrient Supply Beware of an opening in forest cover 21 Adapted from Porté et al. 2011 BMC Ecology Take Home Message No eradication but local elimination and control Girdling and seedling removal : best methods •Beware of timing •Beware of light and nutrients availability 22 The Negundo Team And all the people from the Gers river management center, Bruges National Reserve, Natural Park of Landes de Gascogne, Pierroton 23 Hermitage Experimental Unit [email protected] .
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