Subject: Re: HELP: ERADICATION OF AZOLLA

From: [email-masked]
Date: Mon, 3 Apr 95 12:37:17 +1200

In Article <[email-masked]>
[email-masked] (mel turner) writes:
>In article <[email-masked]> [email-masked] writes:
>>[email-masked] (mel turner) writes:
>>> [email-masked] writes:
>>>>I am making this enquiry for a friend who is farming in a dry region of 
>>>>South Africa. His dam is overgrown with Azolla to the extent that the
>>>>entire water surface has been covered. Does anyone have any experience 
>>>>with eradicating this water fern?
>>>>Any help would be much appreciated   
>
>     As someone else posted,  Salvinia would be using the excess (farm 
>runoff?) nutrients from the pond water, whereas Azolla would in addition be 
>able to fix atmospheric nitrogen.   Someone with say, a rowboat, a long &  
>fairly fine-mesh net, and assitants on shore should be able to skim large 
>areas of pond surface fairly quickly, and the effect would be to remove large 
>amounts of excess nutrients from the water that could then be returned to the 
>soil.
>mdt

Thanks for your suggestions everyone. I spoke to a scientist who said the
only way to control it effectively using chemicals was to spray with paraquat.
He said if the dam was deep enough the fish would not suffer toxic effects. I
feel the best option to avoid damaging the dam is to harvest it. I will send
the farmer your thoughts and let you know what eventually happens.
Christine. 

From [email-masked] May  1 18:15:40 1995
Date: Sat, 29 Apr 1995 07:23:31 -0700
From: Adolf Ceska <[email-masked]>
To: [email-masked]
Subject: BEN # 100

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

No. 100                              April 29, 1995

[email-masked]        Victoria, B.C.
-----------------------------------------------------------
 Dr. A. Ceska, P.O.Box 8546, Victoria, B.C. Canada V8W 3S2
-----------------------------------------------------------

BOTANY BC - JUNE 20 - 22, 1995 - SOUTH CHILCOTIN
From: Allen Banner <[email-masked]>

Planned  location:  South  Chilcotin,  Timberwest  Gaspard Creek
Logging Camp (approx. 90 km southwest of Williams  Lake;  40  km
south of Riske Creek)

Accommodation:   Limited   indoor  sleeping  accommodation  (?30
      people) but plenty of camping opportunities

Dates: June 21 through 23rd, 1995

Tentative agenda:
June 21st: Registration and icebreaker (evening)
June 22nd (am): indoor talks
June 22rd (pm): field trip to grasslands and wetlands
June 23rd (all day): extensive  field  trip  to  grasslands  and
      wetlands (2 groups)

Field trips are planned to: Jamieson Meadows (large diversity of
wetlands),  Gang Ranch/Dog Creek grasslands, Junction grasslands
(Junction of Chilcotin and Fraser Rivers), Farwell Canyon, Other
Chilcotin grasslands and wetlands in the area.

Confirmed Speakers: Trevor Goward (grassland  lichens),  Shirley
Saulkeld  (botanical  illustrations),  Maryanne  Ignace  / Nancy
Turner  (ethnobotany),  Allen  Banner  /  Will   Mackenzie   (BC
wetland/riparian classification), Anna Roberts (local wetlands -
field trip).

Contact:  Allen  Banner ([email-masked] ; tel 604-387-
6688) soon if you are interested in attending. A mailer will  be
going  out  within 2 weeks to our ever-increasing list of Botany
BC "ites" with more details.

MOSQUITO FERN - AZOLLA CAROLINIANA - NEW FOR BRITISH COLUMBIA
From: Frank Lomer, Honourary Research Associate, UBC Herbarium,
         Vancouver, B.C. c/o <[email-masked]>

In December 1994, I was exploring a peat bog  in  South  Burnaby
and  came  across  a small plant I had never seen before. It was
floating at the edge of a large pond in an old  peat  extraction
site  with  Lemna  minor  and  Spirodella  polyrhiza.  It  was a
Mosquito Fern (Azolla sp.), a small free floating  annual  fern-
like plant.

Two  species  of  the genus Azolla are known to occur in British
Columbia:

Azolla filiculoides Lam. is an introduced plant from Europe.  We
      have  collections  at  UBC  only  from  within the city of
      Vancouver. I have not seen it myself except in  a  nursery
      pond (sold?) with aquatics. It can be distinguished by its
      larger  size  (1-10  cm  diameter)  and the rather thickly
      papillose upper leaf lobes.

Azolla mexicana K.B. Presl is known in Canada only from  several
      places  around  Shuswap  Lake (Brunton 1986, Goward 1994).
      There is some dispute as to whether it is native or intro-
      duced there. It can be identified under  a  microscope  by
      the   crosswalls   within  the  barbed  hairs  (glochidia)
      projecting  from   the   massulae   (an   aggregation   of
      microspores).

The  plants I collected were tiny (all under 1 cm, mostly only 5
mm in diameter) and the upper leaf  surfaces  were  smooth.  The
plants contained no spores.

A  month  later,  I found the same plant growing in a deep ditch
transecting a huge cultivated cranberry field in  Richmond  near
the  Fraser  River.  It  was growing so thickly that it formed a
mass of living and dead plants a few meters square and more than
10 cm thick in places. It was clogging the culvert debris screen
and lots of dead plants had accumulated along the ditch bank.  I
saw  more  plants  at  another  culvert further along the ditch.
Again, I could see no spores.

On March 5, 1995, I  saw  another  large  accumulation  of  this
Azolla  species  floating  at the end of a deep ditch at another
section of the same cranberry field about 2.5 km  further  west.
All  were  dead  plants. This time I could see a yellowish-white
powder scattered over the surface of the  debris.  These  turned
out  to  be microspores which I collected and examined under the
microscope. The  glochidia  were  all  without  crosswalls.  The
species  I  found  fits  the  description  of Azolla caroliniana
Willd., and eastern North American species known in Canada  only
from  1962  collection from Hamilton Beach, Ontario which is now
assumed extirpated (Cody & Britton, 1989).

The three areas where I found this plant  contained  many  other
species  native  to  eastern  North America, probably introduced
with cranberry stock from long ago.

The voucher specimens are deposited in the UBC herbarium:
"Richmond, near River Rd. E of No  8  Rd.  In  slough  along  CN
tracks  running  along  edges of cranberry bog. January 2, 1995.
Coll. Frank Lomer."

References:

Brunton, D.F. 1986. Status of  mosquito  fern,  Azolla  mexicana
      Salviniaceae  in Canada. Canad. Field-Naturalist 100: 404-
      408.
Cody, W.J. & D.M.  Britton.  1989.  Ferns  and  fern  allies  of
      Canada. Research Branch, Agriculture Canada. 430 p.
Goward,  T.  1994.  Mosquito  fern:  Two  new records in British
      Columbia. Cordillera 1(2): 23-25.

CALL FOR SLIDES OF BRITISH COLUMBIA & ALASKA PLANTS
From: Deb Sholly, US Forest Service, Ketchikan, AK (Phone:  907-
      225-3101)

We are looking for slides of the following plants:

Draba borealis var. maxima     Platanthera gacilis
Draba kamtschatica             Puccinellia glabra
Draba kananaskis               Puccinellia kamtschatica
Hymenophyllum wrightii         Senecio moresbiensis
Isoetes truncata               Stellaria ruscifolia
Ligusticum calderi                        spp. aleutica

I would like to know what photos are coming, so would appreciate
a phone call. You can send them to:
Deb  Sholly,  Ecology,  US  Forest  Service,  Federal  Building,
Ketchikan, Alaska 99901. - Thanks!

COLEANTHUS SUBTILIS ALERT
From: Adolf Ceska <[email-masked]>

I visited Shuswap Lake last weekend and  to  my  surprise  found
large  stands of moss grass (Coleanthus subtilis) in full bloom.
It looks like the most ideal time to look for this  grass  along
the  mud  flats  of those lakes and rivers that are fed by water
from glaciers and mountain snow.

In the fall of 1989 we (my wife Oluna,  Bryce  Bancroft  and  I)
found Coleanthus subtilis along Shuswap Lake; this was a new for
British  Columbia  and  Canada.  Previous collections from North
America were from Oregon  and  Washington:  Sauvie  Island  near
Portland, muddy shore of Hayden Island at base to I5 bridge, and
Bingen.  In  1989  we tried to find Coleanthus on Sauvie Island,
but we found only a few plants on Oak Island, at the N end of  a
slough where the road to a boat ramp crosses the dyke.

Coleanthus  subtilis  is  an annual grass and it flowers late in
fall, and evidently also early in spring. Due to its small  size
and  short  time  span when it can be found, Coleanthus has been
rarely collected. Now it is time to look  for  it!  I  would  be
interested in learning more about the distribution of this plant
in the Pacific Northwest. If you find it (and I am sure that you
will  if  you try), make a collection and write me the location.
Thanks.

A CENTURY OF BEN
From: R.T. Ogilvie <[email-masked]>

The hundredth issue of Botanical Electronic News should not pass
without some comment. In Botany there  are  various  plant  cen-
turies, some pertinent to our purpose, others that are not.

The  genus  Centaurea  (Asteraceae)  has  nothing to do with one
hundred. The name comes from the Greek kentron  -  a  spur,  not
centum - a hundred. Centaurea includes notorious species such as
the  noxious  knapweeds,  star-thistle,  etc.  The name of these
plants comes from Chiron the Centaur,  half-man  and  half-horse
who,  according  to  myth, taught the medicinal herbs to the an-
cient Greek medical-botanists such as Asclepias. Various species
of  Centaurea  have  been  used  as  herbal  tonic,   stimulant,
diuretic,  diaphoretic, purgative, vermifuge, and goodness knows
what else.

Another genus Centaurium  (Gentianaceae)  has  several  species,
called  Centaury,  which  have been used as herbal and medicinal
tonics. This genus is also named for Chiron the Centaur.

The Century Plant - Agave  americana,  got  its  name  from  the
belief that it flowered only once in a hundred years. In fact it
flowers  more  frequently  than  that, but at least the name has
something to do with a hundred.

Lastly, a Century of Plants, is a set of 100 dried, pressed, and
labelled plants specimens, distributed to  herbaria.  As  a  UBC
student  I  recall  Dr. Krajina assembling bundles of "Centuria"
for exchange with other herbaria. Also, Bernard Boivin,  another
classical  botanist,  issued  sets  of "Centurie de plantes" for
exchange in the early 1950's.

So finally we're back to a  Century  of  BEN,  and  Adolf  Ceska
should be congratulated on achieving this. We hope BEN continues
for at least another hundred issues.

RE: BEN CENTURY - REPLY TO R.T. OGILVIE

Thank  you,  Bob,  for  your  note  and thanks to all of you who
contributed to BEN and made its century possible.

At this moment BEN has about 470 direct subscribers and is  also
posted  on  USENET  in  bionet.plants.  I  rarely  hear from the
readers, mostly only when I do something wrong. For instance:

BEN # 98: " Any superficial disparities  can  only  be  detected
when the spores of the truffle -- which can range in size from a
pea to an orange -- are examined under a microscope."

> Adolf,
> WE were amazed at truffle spores the size of an orange.
> This is surely a record. The truffle that produces them
> must be immense.
> Wilf [Schofield] & Olivia [Lee] [UBC Herbarium]

Please,  don't write me notes saying that you read BEN and enjoy
or hate it. Instead,  I  would  greatly  appreciate  any  notes,
articles  or news that you would like to post on BEN. It is you,
BEN readers and BEN contributors, who can keep BEN running.

WILDFLOWERS HOME PAGE
From: [email-masked]

I have started a WILDFLOWERS home page which might be of  inter-
est to your subscribers of BEN. Their input to WILDFLOWERS would
certainly  make  the  page  more  useful  and  meaningful to the
readers.

Thanks for your consideration.

Gary Lipe, [email-masked]
PO BOX 11830, Ft Worth, TX 76110-1830
Visit the WILDFLOWERS page at:
http://rampages.onramp.net/~garylipe/