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> Volume 72 (January/February 2005, pages
34 - 37)
Begonia bogneri
by Rudolf Ziesenhenne
Ann Salisbury in this issue writes about strolling
through the Begonian pages of the past and the people you will meet. But
there is also invaluable information about begonias there. I had been
trying to get someone to write about B. bogneri to go with a photo taken
by Janet Welsh in 6/04; this begonia was also beautifully present at the
San Diego Convention Show. But looking in an old Begonian, I found that
the perfect article had already been written, more than 30 years ago, and
it is as relevant today as then. I have taken excerpts below, but it is
worth while to search out this edition of the Begonian and read the
whole.
A chance remark to Josef Bogner, inspector of
the Munich botanical Garden, Germany, when I visited the garden in August
1969, that not half of the world's begonia species have yet been
discovered and named, was the opening which gave me an opportunity to see
a most unique begonia which Mr. Bogner had recently discovered, and
subsequently to grow, propagate, and now describe the new species.
The recent discovery of Begonia bogneri had
occurred on January 23, 1969 in the Malagasy Republic (formerly
Madagascar), while Mr. Bogner was visiting the very little explored
mountainous Presqu'lle de Masoala in an area called Hiataka which has an
average annual rainfall of about 3500 mm (140") and a yearly average of
230 rainy days. He was looking for aroids but found at an elevation of
about 50 meters (165') in the deep shade of steep, mossy, granite cliffs
the grasslike begone we are naming Begonia bogneri covering the
naked rocks among mosses, ferns and sometimes Pothos scandens.The
locality of this new species is very small, no larger than one hectare
(2.471 acres); the mountains at Hiaraka arising from sea level immediately
to about 1000 m. (3300'). Mr. Bogner climbed to the top but found no other
place where the begonia was growing.
Hiaraka can be reached only on foot or by boat and Mr.
Bogner was brought there by motorboat from Maroantsetra, traversing the
Baie d'Antongil, by Mr. A. Peyrieras, entomologist at ORSTOM (Office de la
Recherche Scientifique et Technique Outre-mer) in Tananative.
Mr. Bogner collected living plants and herbarium
specimens of the new begonia under his number Bogner 261. Living plants
were sent to three botanical gardens in Europe, but they survived only in
Munich where the plant was propagated.
After Mr. Bogner sent me plants of this unusual
begonia, I studied the begonia literature in order to determine whether it
had already been described and named; it appears it has not.
I have grown this begonia in a terrarium where the
plant readily produced male flowers, but it was not until the plant was
put under fluorescent lights indoors that a female flower appeared. A
study of the flowers placed the plant in Begonia section Erminea A.
DC. Plants in this section have male flowers with four tepals and female
flowers with six tepals. Begonia bogneri has an erect stem, a
leafstalk which is not readily discernible, the dried leaf and its petiole
being 9 cm (3 1 /2") long and 1.5 mm (1/16") wide. The leaf is essentially
the same width its entire length, being strap-like in shape; the nerves
are arranged like a feather, but the side nerves are not visible . ...
The plant Mr. Bogner designated from the wilds as the
type specimen is only 10.1 cm. (4") tall. However I will first describe
the plant as I know it in cultivation.
This plant is being named Begonia bogneri in
honor of its discoverer. Its outstanding characteristics are its narrow
and long leaves (Figure 1.) The leaves of the growing plant are about 2
mm. (1 /8") wide and 15.2 cm. (6") long, medium green with the upper
surface shiny without any appendages. The leaf remains the same width its
entire length; the tip comes quickly to a rounded point. Little pits
appear here and there on the upper surface of the leaves (only visible by
a lens.) That there is one nerve running the entire length of the leaf is
easily observable because it is depressed into the leaf. No side veins are
visible although a study of the cross section of the leaf does reveal
lateral nerves each of which terminated in a little saw tooth. On the edge
of the leaf . ... When grown in the open greenhouse without artificial
light, the plant has a dormant period of a plant which produces a swollen
stem base . ... The plant I received from Munich appeared at first to be
stemless. With time the stem became visible, reaching by January 1973 a
length of 3.1 cm.(1 1 /4")....
To me B. bogneri is a most unusual plant and a
valuable addition to any begonia collection. I like the plant as it is,
but wonder what hyridizers will do with it.
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Above is Janet Welsh' photo of B. bogneri and
below is the photo by J. Bogner that accompanied the original
article in 1973. Even the editor has been able to keep this little
jewel alive so if you can find one, by all means try it! |
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I have found B. bogneri to be an excellent
terrarium plant and under lights it has been evergreen. I have grown the
plant in sphagnum moss, in a mixture of peat, vermiculite, pearlite and
limestone, as well as in my regular soil mix, and have had good results.
In my opinion the plant is most attractive grown in moss or fibrous peat
on cork as a hanging plant as Mr. Bogner grows it as shown in the
photograph. In cultivation the plant develops into a clump consisting of a
number of stems all arising from the one tuberlike body . ...
And a wonder to me is that if the tiny leaves, either
whole or in part, are planted in moss, they eventually produce new
plants!
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