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 December
2000
 Chamaecyparis
obtusa
'Kosteri'
November
2000
Epimediums
 October
2000
Asplenium
trichomanes
September
2000
Gentiana
paradoxa
August
2000
Allium
cyaneum
July
2000
Geranium
dalmaticum
June
2000
Lewisia
rediviva
May
2000
Sanguinaria
canadensis
'Multiplex'
April
2000
Pulsatilla
slavica
March
2000
Crocus
ancyrensis
February
2000
Cassiope
lycopodioides
January
2000
Corallorhiza
maculata
Archive 2004
Archive
2003
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2002
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2001
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1999
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1998
Archive
1997
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Plant
of the Month
October
2000
Asplenium
trichomanes
by Iza Goroff
Asplenium
trichomanes, the Maidenhair Spleenwort, is a member
of a genus containing over 700 species, one of the largest
of fern genera. Asplenium
trichomanes has a very wide distribution in North
America, Europe, and Asia. It is commonly found on both acid
and alkaline rock formations in shady situations.
Asplenium
trichomanes is a small fern, growing about 10" (25
cm) tall and somewhat wider than that. The fronds are
evergreen with leaflets shaped somewhat like those of the
Maidenhair Fern, Adiantum
pedatum. A number of mutants of
Asplenium trichomanes with
unusual leaflets have been selected, propagated, and
distributed.
It is a
very hardy fern, growable in all of the non-tropical United
States and Canada. It does require shade and moisture,
although it needs excellent drainage. For best results plant
it in a vertical crevice between two rocks. The soil should
be a light mix with some humus and (optionally) some lime
chips.
Propagation
is by spores or division. Spores form in tiny spore cases
(sorii) attached to the underside of the leaflet. To
propagate by spores wait until the leaves are almost mature.
One can determine this by the color of the sorii; immature
sorii are light green; they darken as they mature. Lay a
frond on a sheet of white paper. Cover it with another sheet
of paper. As the frond dries it will release the dust-like
spores onto the white paper. These can be dusted onto a
sowing sterile medium in a sterile covered clear top
container topped with a thin layer of small stone chips.
Keep the medium moist. Eventually prothallia form little
heart shaped leafy structures, the intermediate stage in
fern multiplication. Each prothallium produces both sperm
and eggs. The eggs stay attached to the prothallium. The
prothallium emits sperm which rely on the presence of a film
of water to find another prothallium with eggs to fertilize.
Eventually a tiny fern starts to grow from each fertilized
prothallium. One may divide the crown with a sharp knife,
making sure that each part has roots.
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