The bright
colors of newly opened flowers carpet the road ditches, and this makes riding
my bike a little more dangerous. I am risking skinned elbows and broken bones
as I crane my neck to attempt ride-by plant identification, or swerve onto the
soft shoulder to get a better look. It
is worth it to greet old friends.
Sometimes in
February when the ski tracks on the Birkie Trails are just perfect, I wish it
could always be ski season. Then spring arrives in all its glory. In any
season, I love seeing a delicate white dusting in the ditches and forests. Of
course, right now the white dusting is flower petals instead of snowflakes.
Three
species with white flowers stand out in my mind this week. Starflower is one.
They are aptly named, since their white petals reflect light so brightly that
they seem to glow from within, and overexpose any photo I take of them. This
low plant has a whorl of lanceolate (long, narrow, but wider in the middle)
leaves with many delicate veins. Up to three flowers seem to float above the
whorl on slender pedicels. What makes this flower truly unusual is the number
of petals. Sets of seven are very rare in nature!
Often
growing nearby in the sun-dappled edges of northern woods are Canada
Mayflowers, sometimes called False Lily of the Valley. A shady patch of their
small oval leaves may bear no flowers at all. Sometimes just a few plants in a
patch will grow a taller stem with two or three leaves and a spike of
snowflake-like white flowers. The single leaves may help provide a “chosen
plant” with the added energy it needs to bloom and set seed. Since the plants
in a patch are clones connected by underground stems, all the little sugar
factories can work together. As all hardy northern residents know, teamwork is
necessary in the face of poor soil and short summers!
The third
white flower that caught my eye has a couple tricks up its leaves, or rather,
in the flowers themselves. Bunchberry is the smallest plant in the Dogwood
family. With radiant white flowers in the summer and brilliant red bunches of
berries in the fall, this common plant is always a treat to see. And it is more
than meets the eye! The four white things masquerading as petals are actually
sepals. We usually find sepals as the small green leaves cupping a flower.
While the sepals of bunchberry flowers are unusually showy, the petals are
unusually dinky.
Small though
they may be, the cluster of tiny flowers bears petals designed like a catapult.
When the flowers are ready, the lightest touch of a potential pollinator’s foot
will trigger the petals to burst open in less than a millisecond. This triggers the stamens to shoot up and
fling pollen grains with the force of a huge explosive.
According to
J. Edwards, et al, the authors of the original study published in the journal
Nature:
“Bunchberry
stamens are designed like miniature medieval trebuchets — specialized catapults
that maximize throwing distance by having the payload (pollen in the anther)
attached to the throwing arm (filament) by a hinge or flexible strap (thin
vascular strand connecting the anther to the filament tip). This floral
trebuchet enables stamens to propel pollen upwards faster than would a simple
catapult. After the petals open, the bent filaments unfold, releasing elastic
energy. The tip of the filament follows an arc, but the rotation of the anther
about the filament tip allows it to accelerate pollen upwards to its maximum
vertical speed, and the pollen is released only as it starts to accelerate
horizontally.”
The pollen
experiences 800 times the acceleration that the Space Shuttle does during
liftoff, and is launched more than ten times the height of the flower. From this lofty height of 2.5 cm, they can be
more easily carried by the wind. Or the soaring pollen might smack into a bee
and travel to a different flower that way. Bunchberries cannot self-pollinate,
so this cross-pollination is necessary.
Flowers like
these are worth a little swerving as I ride down the road. Those who are risk
averse may choose to walk instead. In either case, drivers should be alert and
give a wide berth to the many bikers and walkers out enjoying the wildflower
gallery along our roadsides.
For over 44 years, the Museum has
served as a guide and mentor to generations of visitors and residents
interested in learning to better appreciate and care for the extraordinary
natural resources of the region. The Museum invites you to visit its facility
in Cable at 13470 County Highway M. The new exhibit, STAR POWER: Energy from
the Sun, opened in May 2012 and will remain open until April, 2013. Find us on
the web at www.cablemuseum.org
to learn more about our exhibits and programs. Also discover us on Facebook, or
at our blogspot, http://cablemuseumnaturalconnections.blogspot.com/
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