Spring
ephemeral wildflowers have figured out that they can make use of the rich soil
in shady depths of deciduous forests, so long as they get a head start on the
trees. Partly because they only show up for such a short time each spring, they
have captured many a heart. They also capture many a photon.
Photons
are little packets of energy that travel through space. We know them as light. They carry energy from
the Sun (released during nuclear fusion reactions) down to Earth. Once here,
they provide almost all the energy for life on Earth. Plants, like these lovely
spring ephemerals, are an essential link between the Sun and animals, since
animals cannot capture sunlight on their own.
For
just a few short weeks in spring, the flowers I mentioned above are absorbing
photons like crazy, and using them to help split carbon dioxide from the air
and water from the soil, and recombine those molecules into sugar. Sugar is simply carbon, hydrogen, and oxygen.
This
month, I am exploring the process of photosynthesis with first graders who come
to the Museum for field trips. We act out a food chain starting with the Sun,
and then shrink down so we can be magically transported into a leaf. There we meet Chef Chlorophyll, the green
pigment that mixes the ingredients of photosynthesis. The students race around
the yard, gathering sunlight (yellow water), water (blue water), and air
(drinking straws) to create a frothy green soup in the mixing bowl. Then we
each eat a grape, and consider how plants produce the sugars that we eat every
day in a hundred different forms.
The
sugars produced by spring ephemerals are not distributed in sweet fruits,
though. These plants mostly produce hard, dry seeds without the juicy cradle of
flesh like apples and cherries. Instead, their precious sugars are stored as
carbohydrates (complex sugars) in starchy roots. Burrow your finger into the
soft soil near any of these plants, and you will soon pull out a small white
tuber. The tubers of trout lilies and spring beauties have a mildly sweet
flavor. Leek tubers store their sugar with an oniony kick. Dutchman’s breeches and
bloodroots store their sugar with toxins added.
The
spring ephemerals used the energy stored in these tubers to get a head start on
the tree leaves this spring, and they are rushing to replenish their pantry for
yet another year.
All
summer long, other plants will be capturing the energy from photons of sunlight
and storing it in their roots, stems, leaves, flowers, fruits and seeds. We
harness that energy in a myriad of ways. Think about that as you eat you dinner
salad, turn on the television, plant your garden, drive your car, and drink
your morning coffee! Energy from the Sun is integral to every aspect of our
lives.
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