Sunday, April 10, 2016

A fondness for ferns

























 Only spread a fern-frond over a man's head and worldly cares are cast out, and freedom and beauty and peace come in.  ~ John Muir

With this quote comes a vision of resting in a grotto on mossy rocks, arching ferns casting a delicate tracery of shadows below my feet.  Why are ferns so magical?  Is it because of folklore, its fractal-like intricate leaf patterns, or do we sense the ancient echoes of prehistoric environments?

Fern folklore
An old folklore belief is that because fern “seeds” were invisible, then one could become invisible when these seeds were eaten or carried.  Several inventive and amazing rituals were created to capture these elusive seeds.  An Irish legend reveals that ferns are flower- and seed-less because St. Patrick cursed them for harboring snakes.  The cross-section of the fern stem is said to bear the name of Christ, and thus provide protection from goblins and witches.  The shapes of fern spikes and the lobes of its leaves were thought to provide healing elixirs for snakebite (the spikes resemble serpents), and ailments of the spleen (resemblance to the organ).  More legends, wild myths, and wishful thinking is found in a fascinating text “The Economic Uses and Associated Folklore of Ferns and Fern Allies,” by Lenore Wile May in Botanical Review (Oct.-Dec.1978).

Fern leaves
A fractal is a “self-similar” pattern that repeats at different scales, and fern leaves often appear to be fractal-like.  They are not true fractals as fern leaf patterns do not repeat to infinity.  Drawing fern leaves is an adventure in patience and persistence!  Perhaps that’s why I created only a representation and focused instead on the furry rhizome and the wavy leaf margins of this Serpent Fern.  Ferns don’t produce flowers and seeds like the many plants we use for food, medicine, and decoration.  They have a complex reproductive cycle and spread by spores instead of seeds.  You can look at a visual image of this reproductive process here at ScienceLearn.org

A smaller leaf, only about 3 inches long.
Fern evolution
Ferns first appear in the fossil record 360 million years ago, but the ancestors of the species we know today didn’t emerge until over 100 million years ago, when flowering plants began to dominate many environments.  A researcher at Duke University in North Carolina has discovered a unique protein called a neochrome in ferns.  This protein enables them to respond to both red and blue light waves (both ends of the visible light spectrum) and enables them to thrive in the shade of other plants.   You can read more about his study and about ferns and this protein here.  

The fern I sketched is the Serpent Fern (also known as polypody fern, cabbage palm fern, gold-foot fern, or hare-foot fern), Phlebodium aureum or Polypodium aureum.
The scales on this root are a reddish golden brown -
red from the sun?
The scientific names derive from the Greek for:
phlebodium = full of veins
polypodium = many footed
aureum = golden (golden “hairs” or scales on the rhizomes)

This is an epiphytic fern, often growing in the “boots” (old leaf bases) of cabbage palms.  It’s found in Florida and ranges into Central and South America.  It has been studied at Massachusetts General Hospital, Harvard University, and the University of Miami School of Medicine as having chemical properties that protect our skin from damaging UV rays, something Florida has in abundance.  

A microscopic view of the sporangia

Top and bottom sketches:
Strathmore Toned Tan spiral sketchbook, 80 lb, 5.5 x 8.5 in
Sakura micron Pigma black 01ink pen
Faber-Castell Albrecht Durer watercolor pencils (walnut brown, white)
Sakura Koi coloring brush pen (sap green)
Niji waterbrush M

Middle sketch:
Aquabee Super Deluxe spiral sketchbook, 93 lb, 6 x 9 in
Various watercolor pencils
Niji waterbrush M