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BEN # 121

Adolf Ceska aceska at CUE.BC.CA
Sat Dec 9 12:07:55 EST 1995


                                                   
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. 121                              December 9, 1995

aceska at freenet.victoria.bc.ca        Victoria, B.C.
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 Dr. A. Ceska, P.O.Box 8546, Victoria, B.C. Canada V8W 3S2
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IN SEARCH OF THE FERN SEED (PART 2 OF 3)
From: "Robbin C. Moran" <biobrm at aau.dk>
  originally published in the Fiddlehead Forum 22: 37-40. 1995

Uncertainty  reigned  until  1794  when  John Lindsay, a British
surgeon, showed that ferns reproduced from their dust.  He  dis-
covered  this  while  stationed  in  Jamaica,  where  he noticed
hundreds of young ferns arising on freshly  exposed  soil  after
rains.  With  a  microscope, he searched the soil in the hope of
finding a fern seed, but was unsuccessful. Undaunted, he decided
to sow some of the dust-which he  suspected  as  the  true  fern
seed-and keep it in his room for observation.

Lindsay gathered the dust from several weedy ferns and sprinkled
it  over  soil in a flower pot. He placed the pot in a window of
his room, watered it daily, and every  day  or  two  examined  a
small portion of the soil with his microscope. Here he describes
what happened.

   "I could always readily distinguish the dust or seeds from
   the  mould, but observed no alteration till about the 12th
   day after sowing, when many of the small seeds had put  on
   a  greenish colour, and some were pushing out their little
   germ, like a small protuberance, the rudiment of  the  new
   fern.  This  little  protuberance gradually enlarged. They
   had acquired small roots, and the remains  of  the  little
   seeds were still discernible where the roots of the infant
   plant  commenced.  Although  the young ferns were now very
   conspicuous by the microscope, the  naked  eye  could  see
   nothing  but  a  green  appearance  on  the surface of the
   mould, as if it were covered with some  very  small  moss:
   this  was the numberless young plants from the quantity of
   the seed sown. In some weeks this moss began to appear  to
   the  naked eye like small scales which gradually enlarged:
   they  were  generally  of  a  roundish  figure,   somewhat
   bilobate,  but  sometimes  more  irregular; they were of a
   membranous substance, like some of the  small  lichens  or
   liverworts,  for which they might readily be mistaken, and
   of a dark green colour. At last  there  arises  from  this
   membrane  a  small  leaf,  different from it in colour and
   appearance, and shortly  after  another  still  more  dif-
   ferent.  Now  each  succeeding  leaf grows larger than the
   last, till they attain the full size, and are complete  in
   all  the  parts  and  discriminating  characters  of their
   respective species."

Clearly, Lindsay thought he had seen a full-sized  fern  develop
from  a  mote  of  fern dust. He therefore felt certain that the
dust was the true fern seed.

A busy medical practice kept Lindsay from making further  obser-
vations,  until  one  day  he  received a letter from Sir Joseph
Banks, president of the Royal Society of London  and  scientific
advisor to the Royal Botanical Gardens, Kew. Banks asked Lindsay
to  collect  Jamaican plants, especially ferns, and send them to
England for cultivation. Lindsay wrote back that given the  risk
of transporting green ferns over such a great distance, he would
send  some of their seeds instead. Banks must have been flabber-
gasted that Lindsay claimed knowledge of the true fern seed.  He
wrote  back  that  if  Lindsay could furnish the means of making
ferns grow from seed, he would be given  the  credit  of  having
made a valuable discovery, one that he (Banks) would communicate
to the Linnean Society of London.

Lindsay  sent  Banks the seeds along with instructions for their
sowing.  The  result  was  pteridological  history.  Thanks   to
Lindsay's information, gardeners in England learned to propagate
ferns  from spores, and they passed this knowledge to colleagues
in other countries. Ferns began to enrich greenhouses,  gardens,
and  parks around the world. Furthermore, the horticulturists at
Kew began raising ferns sent from far  corners  of  the  British
Empire.  They  amassed the world's largest and most species-rich
collection of living ferns-a distinction held to this  day  (the
Kew   collection   is   important   scientifically  as  well  as
horticulturally). James Edward Smith, a pteridologist and one of
England's leading botanists, commemorated Lindsay for  his  dis-
covery by naming a genus of tropical ferns after him: Lindsaea.

Yet  Lindsay's  observations  raised  more  questions.  Were the
"membranes" or "scales" he observed equivalent to the seed  leaf
or  cotyledon of flowering plants? If the dust was equivalent to
the seed, where were the pollen-producing anthers? (The  pollen,
of  course,  was necessary to "stimulate" the development of the
seed.) How and when did pollination take place? [.... conclusion
in BEN 122]


CIMICIFUGA ELATA - ELWHA RIVER VALLEY, OLYMPIC PENINSULA, WA
From: Ed Schreiner <Ed_Schreiner at nps.gov>

We discovered several "new" populations of Cimicifuga  elata  in
the  Elwha  River  valley during summer 1995. The plant was pre-
viously known to occur in the Elwha - evidently first discovered
by A.D.E. Elmer in the early 1900s. We do  not  know  where  his
specimens  came from but presume he encountered the plant in the
Elwha. At present, we know of 16 sites of 1-5 individuals  along
the  Whiskey  Bend Road in Olympic National Park. The plants are
mostly in the road cut but a few are in the forest above.  Addi-
tionally,  a  sizable  population  of nearly 300 individuals was
discovered on the "Cascade Rock" nature trail  above  the  Elwha
Campground. Here, many plants are within 1 meter of the trail in
the  "trail  cut" but many other individuals occur on the slopes
above and below the trail. All these populations were mapped and
permanent plots established for future monitoring. Our permanent
plots were established so we could potentially  test  hypotheses
concerning  behaviour of the plants as "singles", "groups" (of 3
or more individuals within a 1m2  area)  as  well  as  examining
plant  demography  in  the "undisturbed", "road cut", and "trail
cut" situations. It looks to us  like  the  plants  may  benefit
considerably  from the mineral soil exposed by the human distur-
bance. Most plots were in Douglas-fir/bigleaf  maple  stands  on
steep  slopes  (> 35 degrees). We suspect that there needs to be
some subsurface moisture available. Our results are  in  general
agreement with those of Thomas N. Kaye (Oregon) who has prepared
a  summary  of  populations throughout western Oregon and in the
Olympics.

Interestingly, clusters of individuals in  the  trail  cut  were
always  below  a  larger,  fruiting, individual above. It seemed
that the "parent" dropped seeds  along  the  trail.  Looking  at
genetic  links among clusters and populations should prove quite
fascinating.


CIMICIFUGA ELATA - SOME COMMENTS ON ITS ECOLOGY & DISTRIBUTION
From: Thomas Kaye <kayet at ava.bcc.orst.edu>

In 1992 and 1993, the Plant Conservation Biology Program at  the
Oregon Department of Agriculture engaged in cooperative research
with  three  Bureau  of  Land Management Districts and three Na-
tional Forests in Oregon to evaluate the habitat  of  Cimicifuga
elata  and  the  effects of timber harvest on populations of the
species. Our results are too lengthy to summarize  here,  but  a
few  points  may  be of interest to readers of BEN. For example,
for a rare species, C.  elata  is  unusual  in  having  a  large
geographic range (B.C. to southern Oregon) and widely scattered,
usually small populations. Oddly, though, at the southern end of
the  species' range the populations tend to be quite large (over
1,000 individuals), possibly associated with  cryptic  taxonomic
differences  between  northern  and southern types (Ed Alverson,
pers. comm.) or ecotypic differences.

After sampling populations throughout Oregon, and Washington  to
a  lesser  degree,  we  concluded  that there were three primary
habitat features common to most populations:

 1. Hardwoods in the canopy. Nearly all populations occurred  in
    Douglas-fir forest with some component of hardwoods, usually
    Acer macrophyllum.
 2. Subsurface   moisture.  Some  form  of  subsurface  moisture
    availability was in evidence,  and  populations  were  often
    near creeks or rivers.
 3. North  slopes.  The  majority  of  populations  occurred  on
    northwest to  northeast  aspects  (although  a  few  notable
    populations broke this rule).

It  is very gratifying to hear the results of studies in Olympic
National Park that corroborate these  findings.  We  also  found
many populations along road cuts and trails, and attributed this
pattern  to  increased  light  availability and mineral soil for
seedling establishment.  I  encourage  Ed  Schreiner  to  pursue
studies  of  population  genetics  of this species--indeed, they
could be very interesting.

Incidentally, timber harvest/canopy removal tends to  result  in
rapid growth of individual plants and an increase in the propor-
tion  of  reproductive  plants in the population. Populations in
undisturbed old-growth forest tend to have few or  no  reproduc-
tive  plants.  We  believe  the species' natural distribution is
related to the formation of canopy gaps. Clear-cut  timber  har-
vest,  however,  may  only  result  in  a  short-term  burst  of
reproduction. Information from ten to thirty years after harvest
is sadly lacking, and we suspect that C. elata could be  'choked
out' of densely stocked forest stands. Instead, careful thinning
of forest stands could be beneficial to the species.

Kaye,  Thomas  N.  and Melissa Kirkland. 1994. Cimicifuga elata:
      status,  habitat  analysis,  monitoring,  inventory,   and
      effects of timber management. Final Report. Oregon Depart-
      ment of Agriculture, Salem, Oregon.

      Contact  Tom  Kaye  <kayet at bcc.orst.edu> for copies of the
      report: Oregon Department of Agriculture, 635 Capitol  NE,
      Salem, OR, 97310, USA.

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