Nastasia Merceron Présentation
Transcription
Nastasia Merceron Présentation
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 Seed dispersal by wind and water Fast-growing Resprouts from the stump Dioecious species Source : urban plantations 2 Distribution areas introduced in Europe in 1689 (GB) around 1749 in France Native range Lamarque LJ, PhD (2013) Invasive range 3 Invaded habitats Local distribution Riparian forests and wetlands Fraxinus sp, Quercus sp = LATESUCCESSIONAL SPECIES Acer negundo = INTERMEDIATE POSITION + RIVERBANKS Salix sp, Populus sp, Alnus sp = PIONEER SPECIES 4 Negundo negatively impacts native tree species Density Lamarque et al. 2012 Ecography 5 Negundo dominates native tree species Frequency 1 Adults 0.8 Acer negundo Native tree species 0.6 0.4 0.2 0 1 Acer Fraxinus Alnus Salix alba Populus Sambucus Ulmus negundo excelsior glutinosa nigra nigra minor Saplings 1 0.8 0.8 0.6 0.6 0.4 0.4 0.2 0.2 0 Acer Fraxinus Prunus negundo excelsior spinosa Ulmus minor Populus Corylus Sambucus Salix alba Quercus Crataegus Alnus nigra avellana nigra robur monogyna glutinosa Methods in Lamarque et al. 2012 Ecography Corylus Crataegus Prunus Quercus avellana monogyna spinosa robur 0 Seedlings Acer Quercus Fraxinus negundo robur excelsior Ulmus minor Corylus Salix alba Prunus Populus SambucusCrataegus Alnus avellana spinosa nigra nigra monogyna glutinosa 6 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 Acer sp 40 20 0 Biological Chemical Mechanical Review 50 articles 9 Main methods to control invasive trees Mortality rate (%) of resprouting invasive species 100 80 60 Prohibited in natural areas (wetlands, forests …) 40 All species Acer sp 20 0 Biological Chemical Mechanical Review 50 articles 10 Experimental sites Experiment setting up 1st year of measurements 2nd year of measurements 11 Experimental sites 1%1% 0% 0% 7% Salles 11% 91% Acer negundo Populus sp Alnus glutinosa Ulmus minor Carpinus betulus Quercus robur 4% 1% 1% 0% 22% 72% Bruges 3% 1% 0% 16% 69% Acer negundo Fraxinus excelsior Ulmus minor Quercus robur Alnus glutinosa Platanus sp. Marestaing Acer negundo Ulmus minor Fraxinus excelsior Alnus glutinosa Populus alba 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 High cutting Girdling Cutting + 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 High cutting Girdling Cutting + 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 High cutting Girdling Cutting + 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 High cutting Girdling Cutting + Juglone 16 Experimental treatments Measurments : • Mortality : mortality rate (%) Juglone = allelopathic substance with herbicide properties • Vitality : diameter of the five largest resprouts Large girdling Juglone 1.30 m 1.30 m 0.20 m 0.20 m C H G J Cutting High cutting Girdling Cutting + Juglone 17 Mortality rate (%) 100 Percentage 80 b 60 40 20 a 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 Diameter (cm) 10 8 6 A a B b c 4 C d 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 RGRh (10-3. mm. mm-1. d-1) 10 8 6 4 2 0 Full light C Light Sshade DeepSS Shade N+ Nutrient Supply FullClight Light Sshade DeepSS Shade N- No Nutrient Supply Beware of an opening in forest cover Adapted from Porté et al. 2011 BMC Ecology 21 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]