Title: Common Reed Phragmites sp. Why it is aggressive and how to be controlled
1Common Reed( Phragmites sp. Why it is aggressive
and how to be controlled
http//caliban.mpiz-koeln.mpg.de/stueber/thome/ba
nd1/tafel_065.html
2What is the Common Reed?
- Tall perennial monocot grass
- Grow up to six meters in height
- Family Poaceae (grass)
- The genus Phragmites includes
- Four species
- High phenotypic plasticity making identification
difficult - (Gleason and Cronquist, 1991) (Clayton, 1967)
3- Found on
- Europe
- Asia
- Africa
- America
- Australia
- (Holm et al., 1977)
http//www.parker-river.org/
4Distribution in US
- Green areas indicate
confirmed presence. - Red areas indicate possible but unconfirmed
presence.
http//www.csdl.tamu.edu/FLORA/cgi/b98_map?genusP
hragmitesspeciesaustralis
5Characteristics
- Spreading by
- Rhizomes (underground stems)2/3 of the biomass
- Shoots
- Seeds
http//www.pressplus.com/pinelands/plants/phragmit
es.html
http//www.uwgb.edu/biodiversity/herbarium/invasiv
e
6- Grow in different kind of environments
- Marshes
- Along the borders of
- lakes
- ponds
- revisers
- streams
- Canals (ditches)
- Brackish water
- Disturbed areas
7- Forming large stands or colonies arising from
one or a few seeds or plant piece - Grow in water several feet deep
- Grow under a wide range of environmental
conditions(water reed and dry reed) - Their aggressive growth and tendency to
outcompete other plants - It is an excellent colonizer of disturbed soils
and once established it usually crowds out all
other wetlands plants.
8Impacts
- Ecological damage
- Alter structure and function of ecosystem by
changing nutrient cycles and hydrological regimes
(Benoit and Askins, 1999 Meyerson et al., 2000).
- Decrease native biodiversity and quality of
wetland habitat, waterfowl species (Thompson and
Shay, 1989 Jamison, 1994 Marks et al., 1994
Chambers, 1997 Meyerson et al., 2000). - Bird species in the area were associated with
native, short-grass habitats and were excluded by
Phragmites invasion (Benoit and Askins, 1999). - Fishes
9Impacts
- A very useful grass wherever it grows, especially
in the Mediterranean region, North Africa, and
western North America. Although used extensively
locally, its products do not enter commercial
markets. - James A. Duke. 1983. Handbook of Energy Crops.
unpublished
10Impacts
- Create a good environment for Mosquitoes
- Security and safety
http//www.uwgb.edu/biodiversity/herbarium/invasiv
e_species/phraus_clones01.jpg
11IS Phrgmites indigenous or introduced to N.
America?
Phragmites rhizomes were found in North American
peat cores dated 3,000 years old (Orson, 1999).
(Since 150 years ), there has been a rapid
spread of Phragmites.
12Hypotheses of rapid expansion
- Result of human activities causing habitat
disturbances or stresses such as pollution,
changes in hydrologic regimes, and increased soil
salinity (Lapin, Randall, 1994) - Non-native genotypes of the species may have
been introduced to North America sometime during
the past 200 years( Pellegrin, Hauber, 1999)
13Indications for introduction
- Records from the 1800s t describe Phragmites as
being rare or not common (Torrey, J. 1843) - A historical gap in its distribution was found
in the southeastern states (Hitchcock,1935) - The absence of specialized N. American herbivores
of P. australis in North America (Tewksbury et
al., 2002) - The lack of wildlife use (Tewksbury et al., 2002)
14 A study to approve it
- Saltonstall, 2002
- Reconstruct the invasion history of a species
- Knowledge of historical trends in geographic
distribution and population genetic structure.. - Herbarium specimens.
- Use of molecular techniques( PCR-based )
15- Leaf tissues were collected from green Phragmites
plants during the growing seasons (worldwide) - herbarium specimens also were obtained to
increase the number of samples from locations
outside of North America
16- In samples collected before 1910, a total of 27
haplotypes were identified worldwide - 11 haplotypes are unique to North America and are
considered to be native to the continent - Two haplotypes have a widespread distribution on
multiple continents
17- Within North America,
- Significant changes in haplotype frequencies
between the historical and modern samples - Modern populations show a striking pattern of
expansion in the range of (Native)haplotype M -
18Methods to Control Phragmites sp
- 1- Mechanical Control
- 2- Chemical Control
- 3- Biological control
19 Mechanical Control
- A) Burning phragmites
- Rhizomes are not killed
- over 100 feet away
- B) Cutting phragmites
- Timing is critical
- high cost (several times)
http//www.ocean.udel.edu/cms/dseliskar/surfacefil
m.html
http//www.lastgreatplaces.org/berkshire/issues/ar
t6402.html
20Chemical Control
- Glyphosate( Round up)
- Good for small areas
- One acre costs 60
- No-target effect (bad for soil, water and animal
(fish) - Re-treatment every 2-3 years
- Difficult to be applied in some cases
21http//tncweeds.ucdavis.edu/esadocs/phraaust.html
22Biological control
- From Tewksbury et al., 2002)., 2002)and
(Schwarzlander et al ,1999) - 201 species ( from whole wroled)
- 164 insects, 7 mites, and 30 fungi
- 66 are monophagous
- Diptera ( 58 species) and Lepidoptera (46
species) - Over 70 of all herbivores attack leaves and
stems - Only 5 of the monophagous feed in rhizomes
- 21 species have already been accidentally
introduced to USA.
23Biological control
- In North America
- Only 26 herbivore species are known
- Only 5 of them are natives to US.
- Only 2 are monophagous
- In Europe
- at least 140 herbivore species.
- some causing significant damage
- (Schwarzländer and Häfliger, 1999 Tewksbury et
al., 2002).
24- Groups are divided into
- Attack the below- ground rhizomes
- kill the above gourd- shoots
- reduce biomass
- Attack stems and leafs
- Attack rhizomes and leafs in the same time