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]