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BEN # 284

Adolf Ceska aceska at victoria.tc.ca
Sat Mar 23 02:41:55 EST 2002


BBBBB    EEEEEE   NN   N             ISSN 1188-603X
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BBBBB    EEEEE    NN N N             BOTANICAL
BB   B   EE       NN  NN             ELECTRONIC
BBBBB    EEEEEE   NN   N             NEWS

No. 284                              March 22, 2002

aceska at victoria.tc.ca                Victoria, B.C.
-----------------------------------------------------------
 Dr. A. Ceska, P.O.Box 8546, Victoria, B.C. Canada V8W 3S2
-----------------------------------------------------------

JOINT MEETING OF BOTANY BC and BOTANY WASHINGTON

Joint  meeting of British Columbia and Washington botanists will
take place at Selkirk College in Castlegar, B.C. from June 16 to
June 19, 2002.  More  information  and  registration  forms  are
available at

http://members.shaw.ca/dmeidinger/botanybc/

Interest  will  most likely exceed capacity, so if you are keen,
please register early!


REPLACEMENT OF NATIVE NORTH AMERICAN _PHRAGMITES  AUSTRALIS_  BY
   INTRODUCED INVASIVE GENOTYPES
From: Bernd Blossey [bb22 at cornell.edu]

Background

Until recently, botanists, ecologists, and wetland managers were
debating   whether  an  important  invasive  plant,  _Phragmites
australis_ (Cav.) Trin. ex Steud., or common  reed,  was  intro-
duced  or  native  to  North America. Peat core analyses suggest
that _P. australis_ has been an uncommon member of  mixed  tidal
wetland  plant  communities  in  North America for at least 3000
years (Niering et al. 1977, Orson et al. 1987). In the 19th  but
particularly  in  the  late  20th  century, _P. australis_ began
invading fresh and brackish wetlands in  North  America  greatly
expanding  its  range  and  abundance.  Mixed wetland plant com-
munities are replaced by near monocultures  of  _P.  australis_,
resulting   in   changed   ecosystem  processes  and  associated
detrimental impacts on  native  wildlife  (Marks  et  al.  1994,
Meyerson   et   al.  2000).  The  population  explosion  of  _P.
australis_ is often thought of being facilitated by  changes  in
land  use  patterns  and  hydrologic  regimes, increased distur-
bances, urbanization and eutrophication  (Marks  et  al.  1994).
However,  the very same factors are thought to cause declines of
_P. australis_ in Europe (van der Putten  1997).  Alternatively,
it has been suggested that the invasiveness of _P. australis_ is
attributable   to   introduction  of  more  aggressive  European
genotypes (Metzler and Rosza 1987, Tucker  1990,  Besitka  1996)
but  until  recently little information was available to support
this hypothesis. Regardless of the status of _P.  australis_  as
native  or  introduced,  control attempts are widespread and the
search for potential biological  control  agents  has  begun  in
North America and Europe (Tewksbury et al. 2002).

Discovery  of  native  and  introduced  genotypes  using genetic
markers

Research by Kristin Saltonstall at Yale University  (Saltonstall
2002)  has  now  confirmed  the  present-day existence of native
North American haplotypes (lineages) and of introduced  European
haplotypes. A total of 27 haplotypes were identified of which 11
(A-H,  S, Z, AA) are native to North America (Saltonstall 2002).
Within the North American populations, a continuum of geographic
substructuring exists for the native haplotypes. Types AA, F,  Z
and S are known historically from the Northeast; types E, G, and
H  are  found throughout the Midwest; and types A-D are found in
the South and  Intermountain  West  only.  Two  haplotypes  show
worldwide  distribution (I and M) with M as the most common type
in North America, Europe and Asia. Type I  is  found  along  the
Gulf  Coast and also occurs in South America and Asia. (For more
details see Saltonstall 2002.)

Comparing the genetic  structuring  of  present-day  populations
with  those  available in herbarium specimens collected prior to
1910 reveals significant changes  in  haplotype  frequencies  in
North  America.  While  the  herbarium samples show a widespread
distribution of native haplotypes across North  America,  modern
populations  show  a striking range expansion of the M haplotype
(Saltonstall 2002). Type M has entirely replaced native types in
New England and expanded to the southeast where no historic  _P.
australis_  populations  were  known  to occur. Type M (which is
most closely related to other European types) has spread to  the
West and is also becoming prevalent in the Midwest. It is likely
that  the introduction of type M material has occurred sometimes
in the early part of  the  19th  century,  probably  at  several
Atlantic  coast ports. Over the last 150 years, among-population
variation in North America has declined significantly and  today
the  genetic  structure  of North American populations resembles
that of Europe (Saltonstall 2002).

Discovery of morphological differences between native and intro-
duced genotypes

With the recent discovery of the presence  of  native  and  non-
native  populations  of  _Phragmites_  in  North America we also
discovered easy  to  use  morphological  characters  potentially
distinguishing  native  and  introduced  genotypes.  Preliminary
observations of populations in New  York,  Wisconsin,  Virginia,
Arizona,  and  Louisiana as well as examination of numerous her-
barium specimens indicate that  such  morphological  differences
may  exist.  Please note that these traits are based on examina-
tion of few native clones and need further confirmation. We also
need to increase the sample size  to  assess  whether  the  mor-
phological  differences  between native and introduced genotypes
are consistent across populations and lineages. More details and
pictures are provided at: http://www.invasiveplants.net .

In general, native populations  appear  to  have  a  lower  stem
density,  thinner  more  flexible  stems, and produce a reddish-
purple color on their stems and ligules  in  spring  and  summer
that is not present in non-native populations. When checking for
these differences note that the side of the stems exposed to the
sun  will show the brightest coloration. The reddish color fades
somewhat into a chestnut brown in the fall but  was  still  very
obvious in October in Virginia; in the winter the red stems turn
light  brown  and somewhat gray. The ligules of native genotypes
are bright purple while ligules of introduced  genotypes  appear
green  or  slightly yellow. Stems of native genotypes are smooth
and shiny as if polished,  particularly  in  the  winter,  while
stems of introduced genotypes are tan and dull, rough and ribbed
(ridges visible with the naked eye once the leaf sheath has been
removed).  These  differences  are  easy to recognize by running
your fingers up and down them stems. (Please note  that  a  leaf
sheath wraps around the stem almost entirely. It is important to
remove  the  leaf  sheath  when  checking for stem morphology or
texture.) In instances where native and introduced  clones  grow
in  close  vicinity of each other, differences in stem toughness
become obvious on windy days. Introduced genotypes remain sturdy
and erect and move little while native genotypes easily bend and
swing in the wind. Stems  of  introduced  genotypes  are  almost
perfectly  straight  while  stems of native genotypes often grow
crooked. In the fall and winter, differences in the  density  of
the  inflorescence are also obvious; introduced genotypes appear
to have a much denser and larger inflorescence. Observations  in
New York and Virginia also suggest that native genotypes senesce
earlier  than  introduced genotypes (this is a common phenomenon
in  introduced  species  which  often  show   extended   growing
periods).  In  addition,  an  unidentified fungus attacks native
genotypes with dark  spots  often  clustered  around  internodes
while  introduced  genotypes  do  not show this attack. However,
introduced genotypes are frequently  attacked  by  a  number  of
generalist  fungi  (Tewskbury  et al. 2002). However this attack
(visible as large, variable blackish  areas)  is  restricted  to
leaf sheaths.

We need your help

Our  observations  are based on few native clones and we need to
confirm these morphological differences by  examining  different
genotypes  in  the  field and by growing them under standardized
conditions in a common garden. We  are  currently  developing  a
standardized data record sheet (available by the end of March at
http://www.invasiveplants.net).  We  are  unable  to visit sites
across North America ourselves and depend on your help to refine
our ability to  use  easily  visible  field  characteristics  to
identify  native  and  introduced genotypes. We are particularly
interested in:
 1. Locations of  native  genotypes  across  North  America.  It
    appears  that  most  native  populations  in  the  East have
    vanished or have been overrun by introduced  genotypes.  For
    genotype-specific  management it will be important to record
    the presence of native genotypes.
 2. Information about presence/absence of field  characteristics
    as outlined above or of any other additional traits that may
    help discriminate among native and introduced genotypes.
 3. Seed  collections  from native and introduced genotypes from
    as many different regions as possible. This will allow us to
    establish germination trials to better understand  the  dif-
    ferences  in  competitive  ability  of native and introduced
    clones.
 4. Rhizome collections  from  as  many  native  and  introduced
    genotypes  as  possible. We need approximately 1-2 pounds of
    rhizome material to establish a common garden.
 5. Stem collections (in the  dormant  season)  to  assess  dif-
    ferences  in  insect  herbivores attacking native and intro-
    duced genotypes. We have preliminary evidence from stands in
    New York that  the  insect  communities  in  introduced  and
    native genotypes differ significantly.
We  are  currently  developing  standardized sampling protocols.
These protocols will be posted on the web and we hope that  many
of  you  will  be able to contribute to this important work. For
immediate questions, to obtain instructions for  collections  or
advice please contact bb22 at cornell.edu .

The  work  outlined  above  is a collaboration of the Biological
Control of  Non-Indigenous  Plant  Species  Program  at  Cornell
University,  Kristin  Saltonstall  at  Yale  University, and the
University of Rhode Island. For further information  or  updates
please visit: 
http://www.invasiveplants.net

References:

Besitka,  M.A.R.  1996.  _An  ecological and historical study of
   _Phragmites  australis_  along  the  Atlantic  Coast._  M.Sc.
   thesis. Drexel University, Philadelphia, PA.
Marks,   M.,  Lapin,  B.,  and  Randall,  J.  1994.  _Phragmites
   australis_ (_P. communis_): Threats, management, and monitor-
   ing. _Natural Areas Journal_ 14: 285-294.
Metzler, K., and R. Rosza, R.  1987.  Additional  notes  on  the
   tidal  wetlands  of  the Connecticut River. Newsletter of the
   Connecticut Botanical Society 15: 1-6.
Meyerson, L. A., K. Saltonstall, L. Windham,  E.  Kiviat,  &  S.
   Findlay.  2000.  A  comparison  of  _Phragmites australis_ in
   freshwater and brackish marsh environments in North  America.
   _Wetlands Ecology and Management_ 8: 89-103.
Niering,  W. A., R. S. Warren, and C. Weymuth. 1977. Our dynamic
   tidal  marshes:  Vegetation  changes  as  revealed  by   peat
   analysis. _Connecticut Arboretum Bulletin_ # 22.
Orson,  R. A., R.S. Warren, & W.A. Niering. 1987. Development of
   a tidal marsh in a New England river valley. _Estuaries_  10:
   20-27.  Saltonstall,  K. 2002. Kryptic invasion by non-native
   genotypes of the common reed,  _Phragmites  australis_,  into
   North  America.  _Proceedings  of  the  National  Academy  of
   Sciences of the United States of America_ 99: 2445-2449.
Tewksbury,   L.   T.,   R.A.   Casagrande,   B.   Blossey,    M.
   Schwarzlaender,  & P. Haefliger. 2002. Potential for biologi-
   cal control  of  _Phragmites  australis_  in  North  America.
   _Biological Control_ 23: 191-212.
Tucker,  G.  C.  1990. The genera of Arundinoidae (Gramineae) in
   the southeastern United States. _J. Arnold Arboretum_ 71: 14-
   171.
van der Putten, W. 1997. Die-back of _Phragmites  australis_  in
   European  wetlands:  an  overview  of  the  European research
   program  on  reed  die-back  and   progression   (1993-1994).
   _Aquatic Botany_ 59: 263-275.

Author's address:
   Bernd Blossey, Department of Natural Resources, Fernow Hall,
   Cornell University, Ithaca, NY 14853, USA
   email: bb22 at cornell.edu Web: http://www.invasiveplants.net


DISCOVERY OF NEW CONIFER IN REMOTE FORESTS OF NORTHERN VIETNAM
From: Press Release, Royal Botanic Gardens, Kew

An  extraordinary conifer has been recently discovered in north-
ern Vietnam, identified as new to science by Aljos Farjon, Kew's
conifer specialist. The new species, a  "missing  link"  between
true   cypresses   (_Cupressus_)   and   the   false   cypresses
(_Chamaecyparis_) was found in a remote area of northern Vietnam
in ridge-top forest of extraordinary  biodiversity.  This  is  a
remnant  of  a once-extensive forested region which covered much
of eastern Asia and extended to North America. Only fragments of
the forests now remain and the new conifer is one of the  relict
species left after the last Ice Age.

There are only about 630 living species of conifer but their use
for  timber  makes  them  the most important tree species in the
world.

The new conifer is a small tree with highly unusual  foliage  of
two  sorts on the mature trees; both needle and scale leaves. It
was discovered by a team of  scientists,  which  included  Kew's
orchid  expert  Dr  Phillip  Cribb and colleagues from the Viet-
namese Institute of Terrestrial Ecology in  Hanoi,  the  Komarov
Institute  in  St. Petersburg and the Missouri Botanical Garden,
on an expedition studying the orchid floras of the  karst  moun-
tains of northern Vietnam.

Aljos  Farjon has confirmed that the conifer is a new species in
a new genus and has named it, with colleagues from  Vietnam  and
Missouri  Botanical  Garden,  _Xanthocyparis  vietnamensis_, the
Golden Vietnamese cypress. Apart from the extraordinary  Wollemi
pine  (_Wollemia  nobilis_),  recently  described from New South
Wales, it is the first truly new conifer described since 1948.

Its   closest   ally,   the   Nootka   cypress   (_Chamaecyparis
nootkatensis_),    also    now    transferred   to   the   genus
_Xanthocyparis_, is found in North America. Gardeners will  know
it  as  one  of the parents of the widely grown and much loathed
Leyland's cypress (_X Cupressocyparis  leylandii_).  The  conse-
quence  of  the Vietnamese discovery is that the scientific name
of Leyland's cypress will also have to change.

Sadly, the  Golden  Vietnamese  cypress  is  already  critically
endangered  in the wild. It is naturally rare, confined to lime-
stone ridges in a small area not far from the Chinese border. It
is also prized locally for its fragrant wood which is  used  for
coffins  and  for  making  shrines.  Only  a few semi-mature and
coppiced trees survive.

At a meeting of the World Conservation Union  (IUCN)  in  Taiwan
just  before  Christmas, the Vietnamese scientists, backed up by
Kew and Missouri scientists,  will  propose  that  its  mountain
habitat  should  be established as a conservation area. The Mis-
souri Botanical Garden is currently working on  cultivation  and
propagation  techniques  aimed at the long-term survival of this
new conifer.


BOOK REVIEW: SACKS AMONG THE FERNS
From: Martin Levin in Toronto Globe & Mail, Saturday,  
         March  9, 2002 [abbreviated]

Sacks,   Oliver.  2002.  Oaxaca  Journal.  National  Geographic,
   Washington, D.C.  159  p.  ISBN  0-7922-6521-1  [hard  cover]
   Price: US$20.00 CDN$32.00
   Available in all "better" bookstores.

Drawn  by the spirit of amateurism and his own passion (a third-
generation "fernie" in  his  family),  Oliver  Sacks  joins  the
American  Fern  Society  in  a  small  expedition  to  Oaxaca in
southern Mexico. This book is a slightly emended record of  what
Sacks (an inveterate journal-keeper) observed. Like all the best
journals,  it  has  a  rich immediacy, a sense that we share the
moment of the author's perceptions. Since Sacks is such a lovely
writer, and he and his fellow travellers such fonts of knowledge
about everything from Mexican history to Mayan culture to choco-
late making to the workings of fern evolution,  the  book  is  a
rare treat.

And  ferns  and other flora and fauna are what our traveller and
his fellow pteridologists most enjoy.  He  loves  ferns  because
they're ancient, evoking an all-green hothouse planet before the
advent  of  showy,  explicit flowers. ... Virtually a beginner's
guide to botany, the book is  peppered  with Sack's own drawings 
of ferns.

At its core, Oaxaca Journal is a  potent  paean  to  amateurism.
Sacks  is  almost worshipful in his admiration of those amateurs
whose fieldwork has contributed  mightily  to  the  progress  of
science,  from  the  Reverend  William  Gregor,  who  discovered
titanium, to William Smith, the "father of geology"  now  immor-
talized in Simon Winchester's The Map That Changed the World. It
makes  you  want  to  strap  on your field glasses and catch the
first flight south.

[From the dust jacket: "Oliver Sacks is a clinical professor  of
neurology  at  the  Albert  Einstein  College of Medicine and an
adjunct professor of neurology at the New York University School
of Medicine. A fellow of the American Academy of Arts  and  Let-
ters,  he  is  the Wife for a Hat_, _An Anthropologist on Mars_,
and _Uncle Tungsten: Memories of a Chemical Boyhood_.  He  is  a
member  of the American Fern Society, the British Pteridological
Society, the New York  Mineralogical  Club,  and  the  New  York
Stereoscopic  Society." Another Sack's book full of botany: _The
Island of the Colorblind_.]

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