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 Identifying and Harvesting Edible and Medicinal Plants in
Wild (and Not So Wild) PlacesBy: "Wildman"
Steve Brill
Book Excerpt: Flowers
Flowers make plant identification much easier,
especially for non-woody plants. To identify
something, you need to group it with its relatives, and
separate it from unrelated groups, gradually narrowing
your search. Taxonomy, the science of classifying
living things, goes hand-in-hand with identification.
It’s hard to determine genealogy with leaves: Because
they’re around all season, evolution changes them very
greatly. Unrelated plants in similar environments, with
matching survival strategies, often evolve similar
leaves. Flowers don’t change as greatly because, as
reproductive structures, they’re around for a shorter
time. Natural selection has less opportunity to work, so
flowers retain more of their group’s common
ancestor’s features. Wild roses, for example, evolved
different colors and sizes, but they all look like roses.
Shakespeare got it right: Smelling them confirms their
identity with 100 percent certainty. (It’s amazing how
many beginners don’t think of smelling plants.)
Linnaeus, the eighteenth century Swedish biologist
who invented modern scientific nomenclature,
scandalized plants by classifying them according to
their sexual parts. Long before Darwin, he didn’t know
that related plants had evolved from common
ancestors, but he saw how anatomical similarities
between living things formed natural groups and
subgroups: species, genus, family, class, phylum, and
kingdom. This was a great stride from medieval
botany, where anthropocentric systems competed to
classify things according to their usefulness to man.
Thus rodents and insect pests were grouped together
as vermin.
Common names are still confusing today: The same
plants have different names in different regions.
Unrelated plants have similar names for no reason.
Different edible and poisonous plants may even have
the same name!
Universal scientific names clear up this confusion.
They’re in Latin or ancient Greek—dead, unchanging
languages. This makes them hard to remember, so I
suggest you use them as references: If you compare
information about plants from different sources, check
the scientific names to make sure the plants are
identical. Eventually, you’ll be able to impress people
because you’ll automatically remember the scientific
names of the plants you use the most.
Scientific names are often descriptive, and we’ve
included translations where they’re meaningful.
Sometimes, they’re whimsical: Linnaeus sent scientists
around the world to gather specimens. One became
severely seasick, sailing across a stormy Mediterranean
sea, to collect African specimens. He vowed never to
set foot on a ship again. When it was time to return, he
spent years walking around the entire Mediterranean
Sea. So Linnaeus named a tree after him—a species of
arid areas, that never grows near water.
Flowers evolved as modified sets of leaves specializing
in reproduction. Resting on a base called the
receptacle, they’re arranged on a short stem in
concentric whorls.
What floral parts do we look at to identify plants? The
petals, modified leaves that are collectively called the
corolla, are the most obvious features. Simply noting
their color and counting them differentiates your
specimen from many other plants.
Surrounding the corolla is another set of modified
leaves—the calyx, composed of sepals—usually green.
They’re often smaller and less conspicuous than the
petals—most noticeable when they enclose the
flowerbud. If the petals are fused into a tube, you can’t
count them. But you can enumerate a flower’s basic
divisions by counting the sepals. Sepals also vary:
Some flowers have large, colored, sepals, often
replacing absent petals. Sometimes sepals fuse,
forming a calyx tube.
Surrounding the calyx may be another set of modified
leaves, the bracts—collectively known as the
involucre.
Enclosed by the petals are the reproductive parts of the
flower: The male stamens consist of thread-like
filaments, each supporting a tiny sac-like,
pollen-producing anther.
The female part or pistil consists of three parts: The
stigma, which catches the pollen, is the expanded tip of
the style, a tube for conducting pollen to the ovary.
The ovary is the bulging container of the ovules. It
may be simple or compound. The ovary and ovules
eventually develop into fruit and seeds.
Under selective pressure (the gradual force of natural
selection), these basic structures may change radically.
Some flowers lack male or female parts. Some
reproduce asexually, opening only when the seeds are
mature. Some don’t set seed at all, relinquishing
reproduction to other parts of the plant—asexual
vegetative reproduction. Such non-functioning flowers,
like the day-lily’s, are vestigial: They’re present only
because the genes that create them are still active.
A major distinction between flowers is whether they’re
small, numerous, and inconspicuous, or large and
showy. The former produce way more pollen,
depending on wind and pollen volume for pollination.
Their parts are often so greatly reduced, we hardly
recognize them as flowers. They often cluster as
catkins—long stems bearing stalkless male or female
flowers. Catkins fall from the plant as a unit. Most
wind-pollinated trees, such as oaks and walnuts, bear
catkins. Wind-borne pollen often lands in people’s
noses, causing hay-fever.
Showy flowers are the most highly adapted and
efficient. They entice insects, birds, or bats to pollinate
them. The most advanced are the orchids: Some are so
specialized, one wasp species pollinates one orchid
species: The pollen-bearing part may resemble the
female wasp’s genitalia. The male wasp futilely tries to
mate with it, gets covered with pollen, and flies off in
frustration. Endowed with more libido than brain, he
gets fooled over and over, repeatedly pollinating
orchids without gratification.
A major distinction among animal-pollinated flowers is
whether they’re radially-symmetrical (regular), like an
apple blossom, or bilaterally symmetrical (irregular)
like a violet. Flower shape and color are adaptations
for selecting efficient pollinators. Insects land on a
flower for a meal of nectar or pollen, but not all insects
transfer pollen.
Some flowers, like wood sorrel’s, are bowl-shaped.
Effective and ineffective pollinators alike are admitted.
Others, such as jewelweed’s, have nectar at the end of
a long tube that forms a conspicuous spur. Only
hummingbirds and insects with long tongues, such as
butterflies, gain access (although you sometimes see a
tiny hole at the base of the spur, evidence that a
non-pollinating invertebrate cheated by making a hole
to get to the nectar). Flower and animal head shapes
evolved in unison, like locks and keys, so pollination
and feeding is assured.
Pea-like flowers—members of the legume family, such
as wisteria and black locust—are
bilaterally-symmetrical, with a winged keel similar to a
boat’s, positioned under a prominent flag-like standard,
that attracts the pollinators. You must be a robust,
sturdy insect, such as a bee, to shoulder your way
through the keel to reach the nectar within, picking up
pollen in the process.
Flower arrangement provide further distinctions to help
you identify plants. When the flower is out of season,
the fruit usually retains the configuration. The pattern
may even remain on dead, out-of-season plants.
Stalked flowers often grow on a long central axis, with
the lower flowers maturing first. This is a
raceme—typical of the mustard family. If the flowers
are stalkless, as in the mints, it’s a spike. If the central
axis branches, like a grape’s, it’s a panicle.
An umbel resembles an umbrella. Stemmed flowers of
equal length originate from one point, as with wild
onions. If the lower flowers of the central axis have
longer stalks, and the cluster is flat-topped, you have a
corymb, like the sweet cherry tree’s. When the flowers
at the end of a flat-topped, branched cluster mature
first, you have a cyme, like the viburnums and
elderberries.
It’s also important to note where the flowers originate.
The dandelion arises from the middle of its rosette.
Some flowers grow in terminal clusters, at the tips of
the plants. Others come from the leaf axils, the crotch
between the branch and the leafstalk.
A clover looks as if it has one flower, but closer
examination reveals many small flowers grouped
together into a flowerhead. Here the recurrent themes
of repetition and grouping reap a great advantage. One
insect can pollinate all the flowerhead’s flowers at
once.
The composite family, which includes burdock,
yarrow, and sunflowers, takes this strategy one step
further: The radially-symmetrical flowerhead has two
kinds of flowers: Sterile ray flowers, resembling petals,
radiate from the circumference. They attract insects to
the many tiny, inner, fertile disk flowers. This
arrangement is so efficient, composites outnumber all
other North America families. As always, there are
variations: The dandelion, for example, is a composite
lacking ray flowers.
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